# New CNC, and an air cooled spindle?



## 4DThinker (Feb 16, 2014)

I'm going to gift myself one of the Probotix V90 mk2 CNCs. My annual Christmas gift/shop investment. I hopefully can get it with their new higher gantry sides, and beefier gantry beam. One of the reasons I want the higher gantry sides is so that I can do more 3D carving for thick furniture parts. The notoriously low Z clearance of the Probotix CNCs has meant any previous thick 3D furniture part carving was relegated to our old CNC Shark HD2. 

My reason for posting this is about choosing an air cooled spindle over a router. For those of you that are using the air cooled spindle that probotix provides, what would you consider the strengths and weaknesses of them? 

Was installing/configuring the spindle something you could have figured out yourself?
Does the spindle get warm/hot when running for a long period of time? 
Was cabling for the spindle run through the cable chain when you bought your Probotix CNC with the spindle? How about the 220v power feed?
Does your linuxCNC install have spindle speed control that works via g-code S commands in .ngc files?

I have a feeling there are more questions I should ask. Feel free to offer up any advice/experience you may have using your spindle.

Thanks!
4D


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## Stick486 (Jan 4, 2013)

would water cooled run quieter????


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## 4DThinker (Feb 16, 2014)

Mix of water pump sounds and a spinning spindle or just the spinning spindle? I've never listened to one much less both side-by-side.


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## difalkner (Jan 3, 2012)

4DThinker said:


> Mix of water pump sounds and a spinning spindle or just the spinning spindle? I've never listened to one much less both side-by-side.


You can't hear my water pump or the cooling fan at all. The spindle is very quiet. Watch one of my videos and you'll _*almost *_hear the spindle :wink:

Ok, you can hear it but it is very quiet. The main drawback I've read about air cooled spindles is that they need to run at least 12k rpm to keep themselves cool, unless it's a very short run then you can run them down at 6k rpm should the need arise. The water cooled spindle is cool at any speed within its range.

A given on a spindle over a router is much better runout on the spindle shaft and collet assembly. It's been a while since I read the specs but most spindles are significantly tighter in tolerances than the best router. And the guys I've seen who run routers for long 3D cuts end up replacing them at least annually, some more often, some less.

If you need the link to hear the spindle, here's my YouTube channel - David Falkner Woodworking

David


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## 4DThinker (Feb 16, 2014)

No questions about the advantages of a Spindle over a router. Those are why I'm considering one. The precision/less runout will matter more for the furniture joinery I cut more than for the 3D carving of parts. Getting tenons to fit into mortises with just enough room for glue matters more than being off by an imperceptible .002" on the shape of a table leg before sanding. 

I have a dewalt trim router and clamp that I can use on the new CNC. The $800 price on a spindle from Probotix is a hard hit on my conservative budget for this investment. If I can buy and install essentially the same spindle/VFD combo for under $400 then I'll go that route. I just have no idea what to expect toward getting control of it within linuxCNC. 

4D


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## BalloonEngineer (Mar 27, 2009)

When I built mine, I paid $300 for the combination of the 2.2 kw spindle and VFD (“genuine” Huanyang). I got mine on EBay from a seller that shipped from California. Mine is water cooled, but I just circulate coolant through it from a 5 gallon bucket (sealed with llid to keep out dust) using a cheap pond pump, no radiator. I have never felt any noticeable heat rise even during several hour runs. 

Air cooled eliminates the complexity of running cooling lines, my only question about air cooled is where the air exits and whether it would interfere with a dust shoe.

I have no problem starting, stopping, or controlling speed under g-code control, my G540 has PWM as a built in function. Many VFDs can also be controlled via mod bus over a serial port. Do you know the details of what is inside the probotix controller and whether there is a pwm function or if modbus can be implemented? The VFD should be able to source the 10 volts that feeds into a PWM signal. I would think that this may have been discussed on probotix forums. 

I know you have experience with probotix, but have you looked at what CNC Router Parts kit you could get for the same money? I believe it would be much stronger than even the improved probotix.


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## 4DThinker (Feb 16, 2014)

I've looked at what CNC Router Parts has to offer, but as I've already got a Probotix Meteor and oversee two Probotix CNCs where I work I'm going with another CNC from Probotix. I've just taken a good look at the backplate of my controller and there is a 3-pin VFD port with a VFD ADJ hole/pot next to it. I occasionally let students use my shop and keeping everything the same reduces confusion. 

I've seen several VFD/Spindle "kits" from ebay, and Amazon even sells several variations. Probotix has what looks like good instructions for how to connect to and power up a VFD, and what setting to use with their CNC controllers. I'm guessing all the info I would need can be found on their wiki page. 

I'd still like to hear from anyone who already uses an air cooled spindle from Probotix.

4D


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## honesttjohn (Feb 17, 2015)

4D,

I got the air cooled spindle from Probotix. Comes all set up for your machine including the VFD (which isn't hard to set up). Just plug it all in. You just don't use the router ports. Make sure you get the Sunfar E300 VFD. Len's been switching over to them but make sure. You can buy them from the Tech whatever in Chicago for a couple hundred cheaper, but with Len's it's all set up for your machine and he handles any warranty issues. Mine has been been replaced once under warranty. Mine came with the 220 cord attached and wired - just needing the end plug put on. Ran a 220 line close to the machine - added the plug to fit the outlet. It comes all set up so even dummies like me can make dust.

The vacuum is louder than the spindle when running. It doesn't heat up or interfere with the dust shoe. Plus the VFD has a very wide range of RPMs. 

I've run mine upwards of 20 hours a day during the holidays and think nothing of setting a 12 or 14 hour cut and let her go. For that size machine, I personally think air cooled is the way to go. Lot less hassle and trouble. Look at it as being a quieter fancy router. But you will have to get a set of your own wrenches for the collet and bit changing.

I'm interested in a machine with a higher gantry too. Let us know what you find out and if existing machines (my Nebula) can be retrofitted.


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## 4DThinker (Feb 16, 2014)

Thanks HJ. 

Did you get 1/4" and 1/2" collets with your spindle?
I'm surprised Probotix didn't include wrenches with it. I suspect I've got some that would work. 
Help me understand how it is all wired up... a cable from the spindle goes to the VFD? The VFD plugs into the Unity controller? 220v feeds the VFD and NOT the spindle directly?

I don't currently have a 220v outlet in the room I want to put this new CNC, but my home electrical panel is in an adjacent utility room and the backside of the drywall in the shop room is exposed for easy access. I'll hire an electrician to add a new breaker and run the wire to a new 220v outlet if I decide to go with a spindle. 

I still haven't heard back from Probotix about my desired features for the V90mk2. Holiday weekend now so I expect a reply Tuesday or later this week. 

4D


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## rrrun (Jun 17, 2014)

4DThinker said:


> For those of you that are using the air cooled spindle that probotix provides, what would you consider the strengths and weaknesses of them?
> 
> Was installing/configuring the spindle something you could have figured out yourself?
> Does the spindle get warm/hot when running for a long period of time?
> ...


I bought their air cooled spindle; my install was in September. When they were building someone else's Nebula in the queue in front of mine, they actually gave me his when he wanted to change his order somehow. In any event, my Nebula is wired for both my Spindle & has a 110v outlet so I could use a router if I wanted to.

Installing the spindle was not difficult at all. I got it figured out with the help of my son, the mechanical engineer. You would have no problem at all. The problem I did have was that the illustrations in the Quick Start Guide did not match my unit. Instructions were not exactly correct. You could figure it out, but it did take a minute to think it through.

Yes, the spindle does get warm to touch after a long cut. I haven't paid any attention to that; it is air cooled, after all.

All cabling was in the cable chain. I didn't touch it.

The 220v power feed needs to go to the converter, which is located under the table on the Nebula. The power converter itself has a short pigtail; about 6'. Given the size of the Nebula, my pre-installed power service at the back of the table *barely* reaches, which is a frustration. I wasn't smart enough to ask about that prior to ordering this, my first CNC.

Hooking up the power converter was my big surprise: there is no off switch. I'm turning the unit on by throwing the breaker. No big deal, but not exactly convenient. I wish that there was a unified power center for the computer, control box & power converter. That's on my "I'll get to it someday if I'm incredibly bored" list. I also wish the electronic components were secured in a dust free environment under the Nebula table ... that's something I do intend to fix. In my spare time.

I have controlled spindle speed 2 ways: setting the default speed for each bit in Aspire, and then adjusting it using the slider bar or spindle speed buttons on the main control screen in Linux CNC.

So, I'm 3 months in with my spindle, and I would absolutely do the same purchase again today. Recommended.


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## 4DThinker (Feb 16, 2014)

Thanks Henry!

Nice to know the spindle speed is controllable via Aspire settings. I have access to an industrial Multicam CNC with spindle and tool changer and am very familiar with controlling those features even though both are ignored when using my meteor running a router. 

No OFF switch on the 220v VFD doesn't surprise me. Seems as though there should be a low power or sleep state when the controller/linuxCNC shuts down? Hard to cull any such features from the specs I can find online though. 

Dust proofing we handle fairly well by taping filter material over the air intake of the PC and controller. I open them up and clean them out each semester. If the filter material has remained in place there is usually little to no sawdust inside the cases. We learned our lesson early though by killing a controller by letting it pack itself with sawdust. 

4D


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## beltramidave (Jan 6, 2016)

Last I knew, this was the setup that Probotix was using: https://www.automationtechnologiesi...e/brand-new-2-2kw-air-cooled-spindle-and-vfd/

I have at least 3 machines with their vfd and air cooled spindles that I have set up for work and have not had any issues with then to date.

With my personal machine (not Probotix, but using Linuxcnc), I am using the air cooled spindle from the above link and a vfd from Automation Direct. I have run continuously down to 8000 rpm without any issues. I know people with water cooled spindles say they are quieter, but the noise comes from the cutter mostly anyway. Spindle temp has not been an issue either. You can also get the spindle wrenches from Probotix.

The last I knew, the Probotix spindle/vfd setup did not have a way to disconnect the power (220V) to the vfd, other than by disconnecting the cord. I personally did not like that so I installed a disconnect switch, this way it can be powered down when changing tools and also at the end of the day. The Unity controllers are setup already so that you have control of the spindle speed thru gcode and the slider in the software.

Another advantage of the spindle is that you have more vertical adjustment in the spindle mounting bracket, which can give you a little more height adjustment (which for you, 4D, would be good). Once you get a spindle, you will wonder why it took you so long.

Dave


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## honesttjohn (Feb 17, 2015)

Mine is all manual - one of the earlier ones. The 220 hooks right into the VFD box. You could add your own longer cord if you needed to. The wires just plug in. It has it's own on/off button and a knob to turn to get your desired rpm settings. I have to turn the spindle on and off manually but about 10 minutes on the phone with Len had it all hook up right. It's just a matter of putting the right wires and plugs in the correct place. All I added was a plug end for the 220. Everything else was ready to go. All it takes is to forget to turn it on once (or in my case twice) when you hit go and it's ingrained in the back of your brain. 

You can run your own 220 from the box if you got the extra breaker space.


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## kolias (Dec 26, 2008)

I had an air cooled spindle in one of my cnc’s and the sound it made was worse than a router. That was a kit I bought in USA which came with a Delta VFD, quite expensive. The reason I went with air cooled spindle was to avoid the hustle with the water pump.

Now I have a new cnc with a water cooled spindle and VFD both from China at half the cost. The difference is like day and night. There is no noise from either the spindle or water pump and the performance is amazing.

I will never recommend an air cooled spindle, for the money spent might as well get a water cooled spindle. On the other hand if your shop is noisy (perhaps with a vacuum system running) or if you don’t mind noise then air cooled spindle is fine.


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## subtleaccents (Nov 5, 2011)

Stick486 said:


> would water cooled run quieter????


Air cooled spindles are very quiet. I have a 3HP Columbo air cooled spindle on my 4x8 machine. I can talk in a quiet voice over the sound it makes. As for heating up, I have run the machine for a steady 7 hours during hot summer days and it never heated up. I would think the smaller hp air cooled spindles my not be able to run as long and hard as the commercial Columbo units but it will depend on the cutter size, depth of cut and material.


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## 4DThinker (Feb 16, 2014)

honesttjohn said:


> All it takes is to forget to turn it on once (or in my case twice) when you hit go and it's ingrained in the back of your brain.


I'm in the habit of using the spindle toggle box in LinuxCNC to verify that the router is turned on before starting any job. That is after also learning how important it is the hard way. 

Since many students use the college CNCs it is never safe to assume a router is switched on when starting a job. Some don't shut down linuxCNC properly and it will let the router start to run. The easy fix is simply to turn the router off by its own switch. Of course the next person using that CNC assumes the routers are left with their switch in the ON position. Thus the practice to verify router control in linuxCNC before starting any job. 

4D


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## beltramidave (Jan 6, 2016)

There is a .hal pin in Linuxcnc, I believe it is called "spindle in motion", that I tied to a relay out contact in the vfd that closes when the vfd is "at speed". This prevents the lowering of the Z axis until Linuxcnc sees that contact being closed. I could not depend on an operator to turn on the disconnect or vfd power before running a program. This works very well.

I tried to get Len to start doing that to all machines that used a vfd, but was not successful (as far as I know). You may ask him when you order your machine. It's not real difficult if you have some wiring and programming knowledge. I also put a "at speed" indicator on the operator interface.

Dave


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## 4DThinker (Feb 16, 2014)

Very interesting Dave, and thanks for mentioning it. Glad to see another example of how "smart" LinuxCNC can be when a smart programmer gets ahold of it. 

I do have some programming and wiring knowledge which has already come in handy as I learn more about how linuxCNC works.

4D


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## beltramidave (Jan 6, 2016)

You are welcome. All it takes is 2 more wires between vfd and parallel port, program setup in vfd and a little linuxcnc programming magic. I would be willing to share my linuxcnc changes, but you will need to make sure that you have enough parallel port pins. I have the second parallel port, so that wasn't an issue. 

Happy New Year!

Dave


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## 4DThinker (Feb 16, 2014)

I also have a 2nd parallel port, and used it to wired up a touchpad. I'll get back to this thread if/when I decide to go with a spindle. 

Happy New Year to all!
4D


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## 4DThinker (Feb 16, 2014)

honesttjohn said:


> I'm interested in a machine with a higher gantry too. Let us know what you find out and if existing machines (my Nebula) can be retrofitted.


So far I haven't gotten any response from Probotix. Not sure if they are super busy, ignoring my requests for a quote (as they said on their facebook page they don't like making their V90mk2s), or still on a holiday break. I spent a bit of time staring at my Meteor in contemplation of swapping out the gantry risers, and concluded it would involve taking apart the whole gantry, and extending several cables. Likely more difficult that building a whole new CNC from scratch. 

4D

Update: Just got a message from len: 

"I just don't have an answer yet. We're playing catch up on the barrage of year end burn-up-the-budget orders and I can't take on any special requests right now.

>Len"


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## 4DThinker (Feb 16, 2014)

As we're in February now I sent off another quote request to Probotix. Hoping they have a little time available to work on it. Of course as there is less profit in their V90 MK2s than on any of their larger CNCs, and I want to delete several standard features to save a little money, I can see how they don't put such requests high on their priorities list. 

I don't expect a response until monday at the soonest. I'll post again if/when I hear anything from them. 

4D


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## 4DThinker (Feb 16, 2014)

No response from Probotix, so at this point I've decided to see if I can put together enough parts to build my own small CNC to do the job that I hoped the V90 would do. I've ordered 600mm long linear rails for the Y and X axes. I'm looking for ball screw and ball nut kits for those axes as well. I plan to mock up/prototype the frame and mechanics with hardwood frame members and bb plywood plates. Once I have it conceptually "finished", I'll make steel end plates (cnc plasma cut) and buy aluminum extrusion for the frame members. I've got decent nema 23 stepper motors from an old X-carve kit. I've got a tinyG controller that will drive them. My goal is to end up with a slightly better CNC than what the V90 would have been. The tinyG controller ran these steppers fine in the X-Carve. It was belt driven while my design will need them to spin ball screws. If need be I'll look into a better controller. At this point the tinyG is "free". 

4D


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## RainMan 2.0 (May 6, 2014)

Probotix is not giving me much faith in there company with this type of communication .

Looking forward to seeing your build 4D .
I was wondering where you purchaced your linear rails ,and what size you went with . Not the length of the rail but the size that the blocks ride on , like 20mm etc


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## 4DThinker (Feb 16, 2014)

I bought the linear rails from Amazon.com: 4 of TEN-HIGH CNC parts linear rail HSR15 600mm Approx. 23.62inch Linear Guideway Rail+2pcs HSR15CR Square type carriage bearing block. 

Not the cheapest source, but with Amazon I know I can get my money back if they aren't what I expect to get. 

I'll post images when I start getting the parts together. 

As for Probotix, they've stated on their facebook page that they only have the V90-MK2 in their lineup to provide something to find when people search for their original V90 kit. They don't like making them as they take the same effort/labor to make as their larger machines, but aren't as profitable at the cost they sell them for. I asked for a quote with no MDF bed, no router mount, and no PC peripherals. Unfortunately that is where much of their markup is. As such, I guess making one to meet my request was not worth it when the workers could be making larger machines that are profitable. I respect that they have to make money to stay in business. They've always given me great support on the machines I've already bought from them.


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## Scottart (Jan 8, 2015)

I burned up three routers on my Shark and than my RPTs 48 96. love going to and Air cooled spindle, way more powerful and you can talk next to it during a carve. the Vacuum is way louder. Not a probiotics, but that is my two bits worth. How much vertical will you end up with?


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## BalloonEngineer (Mar 27, 2009)

4DThinker said:


> so at this point I've decided to see if I can put together enough parts to build my own small CNC to do the job that I hoped the V90 would do.
> 4D


I know it is a little late for you, but VXB actually has some pretty complete CNC router “sets” that include the linear rails, bearings, and ballscrews with associated end bearings, etc. For example, for a V90 sized machine, with extra Z height (1 foot x 2 feet x 10 inch z) the complete package is $650. 
2'X1' Feet CNC Router Kit 16mm Rail Guideway System and Ball Screws XYZ Travel 24" x 12" x 10" inch

I’m sure you can probably put together various amazon/eBay packages for less, but these packages look like pretty good quality, VXB is a good brand, and it’s nice to get everything from one supplier. Their pricing is a little odd for this small of a machine, as a set to build a 4 foot x 4 foot machine is only $100 more, and a 4 foot x 8 foot machine (all ballscrew!) is $950.


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## 4DThinker (Feb 16, 2014)

No good advice is ever too late, BE. Thanks for the info. If I don't take advantage of it someone else will. I had seen several sources for complete kits in my search, but many had ship times from China at 2-3 weeks, were from companies I'd never heard of, and/or companies with few good reviews and many bad ones. My Amazon order has already shipped and will be here this week. 

4D


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## 4DThinker (Feb 16, 2014)

Scottart said:


> I burned up three routers on my Shark and than my RPTs 48 96. love going to and Air cooled spindle, way more powerful and you can talk next to it during a carve. the Vacuum is way louder. Not a probotix, but that is my two bits worth. How much vertical will you end up with?


I'm hoping to end up with at least 5" of Z travel and clearance when I'm done. I have a spare Dewalt trim router with precision collet to start with, but plan on eventually replacing it with a true spindle. 

In thinking about the Z axis, I keep wondering if there is a simple way to have two parts telescope down rather than a single plate slide all the way with the router. I could get twice as much travel for the length of the linear rail used. 
I want to have as little as possible follow the router down to keep the cutting area clear for hold-down clamps.

This CNC will also not have a traditional bed, but rather just a special version of my adjustable angle clamping jig. Other jigs for hanging tall parts under the bit as needed. 

4D


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## BalloonEngineer (Mar 27, 2009)

Not a big fan of the traditional Z-axis design, this was one of the main reasons I designed my own

I put the Z-axis rails on either side of the spindle, and the ballscrew off to the side. This way there is much less cantilever putting a torque on the gantry, and the spacing of the Z-axis bearing blocks is greater, so the load/torque resistance is increased. The drawback is you lose travel along the gantry (Y) relative to the linear guide length.









But I also supported my gantry from the back side, so the gantry extends past the vertical supports. My gantry has adjustable height, since it is supported by some 8020 extrusion











Finally, even though the Y-Z carriage is wide, the extended gantry allows cutting almost all the way to the X-axis guide rails, much more usable area than traditional designs










Once you start designing your own you can make it to do exactly what you need. 


Sent from my iPad using Tapatalk


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## 4DThinker (Feb 16, 2014)

I know from many years of experience that all things can be improved with some imagination, determination, and sweat. I've seen a few CNCs with the Z axis mounted between two gantry beams. No cantilever problems to deal with. Of course with guide rails and lead screw in there some width is lost.... unless you make the beams wider than the bed so the router can travel from edge to edge of the bed. 

I'm hoping by starting with wood mockups of the structural parts I won't feel bad changing the configuration of it all as ideas come and go. The base my Meteor CNC sits on is the 3rd evolution, simplified and optimized to eliminate all shortcomings of the 2 previous design. I've played with the CNCs Probotix sells long enough to know that they could be improved, perhaps simplified, certainly strengthened, etc.. There is a "perfect" (ok, 98% perfect) version of the small CNC I want out there to be found. I'll play with variables until I stumble across it. 

4D


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## beltramidave (Jan 6, 2016)

One improvment I would make over the Probotix machines is to makes sure that you have more travel on X&Y than your spoilboard size so that you can surface the whole spoilboard and use your machine to make a new one. Never did really understand why they didn't do that.

Looking forward to your build progress.

Dave


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## 4DThinker (Feb 16, 2014)

beltramidave said:


> One improvement I would make over the Probotix machines is to makes sure that you have more travel on X&Y than your spoilboard size so that you can surface the whole spoilboard and use your machine to make a new one. Never did really understand why they didn't do that.
> Dave


Good advice. 

This small CNC won't have a conventional bed though. I plan on installing a custom version of my adjustable clamping jig in it that will move between horizontal and vertical. I have been contemplating strategies for leveling the jig true to the cutting plane when horizontal, but am initially concluding that by design and being small it will tend to be. The jig mounts to the front rail... level to the X axis travel and square to the Y axis. Parts of the jig are CNC-cut to be square and go together square. When used flat it will have a secondary support that slides under it from the back rail of the bed. This support will always be level with the cutting plane. The jig face is held stiff by supports running under it. The limits of the jig face will match the limits of the X/Y travel, so it could always be milled flat if it needs to be. 

4D


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## Ronald Reome (Jan 5, 2016)

4DThinker said:


> Good advice.
> 
> This small CNC won't have a conventional bed though. I plan on installing a custom version of my adjustable clamping jig in it that will move between horizontal and vertical. I have been contemplating strategies for leveling the jig true to the cutting plane when horizontal, but am initially concluding that by design and being small it will tend to be. The jig mounts to the front rail... level to the X axis travel and square to the Y axis. Parts of the jig are CNC-cut to be square and go together square. When used flat it will have a secondary support that slides under it from the back rail of the bed. This support will always be level with the cutting plane. The jig face is held stiff by supports running under it. The limits of the jig face will match the limits of the X/Y travel, so it could always be milled flat if it needs to be.
> 
> 4D


4D If you are looking for aluminum extrusion,brackets for frame,nuts for alum.and more they have it all.Shipping is very reasonable.I have brought from them and reinforce my meteor frame up.The address is MiSUMi.com phone 800-681-7475 Hope this help you out.Way less money than Amazon. Ron


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## 4DThinker (Feb 16, 2014)

My linear rails arrived. I actually bought 2 sets, one beefy 600mm long and the other smaller and only 300mm long. I've got some nema 17 steppers and had an idea (OK, might have been a brain short) to make a 1/2 scale prototype to use for finalizing the idea before I commit it to full sized parts using much beefier nema 23 steppers. I may be wrong, but 1/2 scale in 3 dimensions should work out to 1/8 the material needed. Half as long, half as wide, and half as thick. 

I was looking for 15mm x 30mm extrusions but have only found 15mm square. Wondering if 15 x 30 is even made. 

4D


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## beltramidave (Jan 6, 2016)

They most certainly do. Here is one source. https://www.amazon.com/80-20-Inc-T-Slotted-Extrusion/dp/B001F0G6CA


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## 4DThinker (Feb 16, 2014)

beltramidave said:


> They most certainly do. Here is one source. https://www.amazon.com/80-20-Inc-T-Slotted-Extrusion/dp/B001F0G6CA


Unfortunately I'm looking for true 15mm x 30mm extrusion. The 1530 is 1.5" x 3". 

4D


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## 4DThinker (Feb 16, 2014)

Len at Probotix finally (He's been out of the country) did get back to me with an offer to knock $200 off the price of a V90 Mk2 less spoilboard, router mount, monitor, keyboard, and mouse. 

As I still want a taller gantry (not available on the V90) and have already started collecting parts, I have declined the offer.

Drop-in nuts for the t-track arrived today. Screws for them are taking a more scenic route from China. 

4D


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## 4DThinker (Feb 16, 2014)

Ball screws ordered for the X and Y axes. It looks like my patience will come in handy with this project, as shipping times for much of what I'm ordering are guesses between 3 days and 3 weeks. Shipping is invariably "free" though, telling me the sellers have plenty of mark-up in the hardware to cover it. 

I intend to draw up vectors in Aspire for cutting out end plates and such. Some sources provide cad drawings of the parts I'm buying. Not all do though, leaving unknown hole positions on all the parts that can't be added until everything is here. I'll cut plywood plates first, and if everything fits fine I can use the same vectors to cut the plates from aluminum. I should have a frame up with X and Y axes moving by end of March. Time will tell.

As I contemplate the design of this small CNC, I have a few "decision guidelines" that may be useful to anyone else out there who is considering the design of a CNC.

1. I won't do anything in the wood prototype that can't be similarly done in the final metal version. Yes, wood screws instead of machine screws is OK, but finger joints in wood have no parallel in metal, so they aren't allowed.

2. No assembly shall complicate access to earlier installed assemblies. (Easy) access to the screws holding all parts in place has priority. I don't want to have to take the gantry off to gain access to Y axis bearings, for example. 

3. No angle brackets. If parts meet at 90 degrees then they must connect with screws. The goal is to have all parts reproducible from flat sheets. 

It turns out than 3/4" Baltic Birch plywood (18mm) and 1/2" Baltic Birch plywood (12mm) add up to 30mm thick if laminated together. I'll be using this combo for frame and gantry beam of my wood mockup. 3060 extrusion for the final metal version. 

4D


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## RainMan 2.0 (May 6, 2014)

Not really a fan of making a half scale version. I was going to build a full scale version out of key slot extruded aluminum, and use 3/4” MDF for the sides of the gantry that hold the rack and pinion and vertical extrusions . Then transfer the MDF to aluminium once the design is proven.

I’ve been looking at CNCrouterparts Pro version , and it looks like it’s a failry easy design to duplicate . Especially now that they have gone to linear rails


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## 4DThinker (Feb 16, 2014)

The half scale version is because I already have nema 17 steppers, it will take up far less space to work on, and should answer many questions about the viability of my design. I can use 1/4" (6mm) and 3/8" (9mm) to end up with accurately scaled frame and beam and end plates, etc.. I'm even looking at what would be close to a 1/2 scale spindle, probably the quiet-cut spindle Inventables sells for the X-carve. 

As I'm not perfectly confident I know the best way to do the Z axis, etc., making test versions at 1/2 scale will encourage more iterations, and use less material. I've seen several youtube CNC-build series where there is a final "regrets" video about all the things the builder would change if he does it again. 

So I may end up with 3. The 1/2 scale in plywood. The full scale in plywood, and then the full scale in aluminum extrusions using the hardware parts from the plywood mockup. 

4D


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## RainMan 2.0 (May 6, 2014)

I didn’t realize you were doing an entire prototype in plywood . Sounds like a good idea, as it won’t be a big expense to absorb that way, and great as a proof of concept.

The video I posted below is an Evolution 2.0 made by a gentleman named Joe . It used to use V bearings and different caraiges , but he’s updated the design with linear rail ,which made it much easier to design and dial in . 
If you watch the video closely , you can see it’s not all that hard to replicate , and I was going to build mine simular . I’m not going to build the carriage that holds the spindle though ,as I’m hoping to buy one from Joe .


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## 4DThinker (Feb 16, 2014)

I still haven't decided how I want to do the Z axis. I've seen relatively simple linear rails with the feed screw integrated into the bearing plate. I want to keep the total cantilevering mass as close to the beam as possible. I also don't want much else coming down with the router when it descends. 

I'm considering using two of the small 300mm linear rails I bought for my half scale prototype, each with two bearing plates on them, spread apart as far as possible but to still leave 6" or so of the rail for up/down travel. Bolt a plate on the 4 bearings that has the ball screw bushing on the back between the bearings. The router/spindle clamp mounts on that plate. The plate can extend down as far as it needs to to get the router collet within a practical range for cutting. 

4D


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## 4DThinker (Feb 16, 2014)

I found and ordered a 300mm ball screw kit that should work for the Z axis. I'll have to see how big the associated parts are before I can finalize prototype 1 of my Z axis idea. I intend to make the back plate of the Z axis 4" wide to match what probotix has done so my current router clamp will fit. Nothing else needs to stick out wider than that.

4D


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## 4DThinker (Feb 16, 2014)

It looks like the Z axis body will end up closer to 5" wide. Each of the linear bearing blocks are greater than 2" long, and I plan to use two on each rail. I've started drawing up details using the dimensions I have so far. Much will be dictated by the size of the parts. 

4D


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## 4DThinker (Feb 16, 2014)

I cut up 3/4" (18mm) and 1/2" (12mm) bb plywood strips today to make 30mm x 60mm beams. These will be for my full scale wood prototype. I also cut some 3/8" (9mm) strips but didn't find any 1/4" (6mm) bb to use for the 1/2 scale prototype. I'll have to dig through my scrap pile to see if I have any. I don't need very much, but the strips need to be 15" or so long. 

4D


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## UglySign (Nov 17, 2015)

4D, you have any pictures of what you're talking about?
Im sorry but I have no clue as to whats going on.


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## 4DThinker (Feb 16, 2014)

I am collecting parts to make a CNC. I'm making a prototype from baltic birch plywood for all the structural parts.

I'm trying to make the plywood parts the same size as they will be when I make a metal version from standard extrusions.


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## 4DThinker (Feb 16, 2014)

My shop yielded enough 1/4" (6mm) plywood to make the 1/2 scale beams. Full sized beams are glued up and trimmed. 

As I examine how my Probotix Meteor is made I wondered why they didn't put the X-axis stepper on the right side where the cable chain is. Shorter cable needed for sure. I believe I've seen a photo somewhere that shows the stepper on the right side. That could have been a mirrored photo though. Just curious if it matters for some reason I haven't discovered yet.

I'll start adding photos when I've collected enough parts to start assembly. 

4D


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## 4DThinker (Feb 16, 2014)

1/2 scale beam material all glued up. When dry I'll rip it into 15mm x 30mm beams for the 1/2 scale frame. 

Most of the hardware I ordered is coming from China, and hopefully will be here before March is done. As there are several sources for the same goods on Amazon, I wish they would do a better job of stating sources (such as China). My linear rails came from Texas, which was a surprise, although that is a port state where ocean going ships unload their goods headed to the middle of this country. 

4D


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## 4DThinker (Feb 16, 2014)

Screws for the linear rails arrived. So did the extra bearing blocks for the small linear rails. M8 nuts will be here Saturday, but M8 screws also won't be here for a couple of weeks. I'm using the M8 screws to attached the end plates to the side rails, and using square M8 nuts dropped into a CNC-cut pocket in the plywood beam ends. 

4D


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## RainMan 2.0 (May 6, 2014)

4DThinker said:


> Screws for the linear rails arrived. So did the extra bearing blocks for the small linear rails. M8 nuts will be here Saturday, but M8 screws also won't be here for a couple of weeks. I'm using the M8 screws to attached the end plates to the side rails, and using square M8 nuts dropped into a CNC-cut pocket in the plywood beam ends.
> 
> 4D


And the pictures are?


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## 4DThinker (Feb 16, 2014)

Not much to see yet. In the photo below are what I've accumulated so far. Left to right:

Linear rails, screws and 2 extra bearing blocks. 1/2 scale material for the frame of the 1/2 scale prototype.
Material for the full sized gantry beam.
4 pieces for the full sized frame.
Linear rails for the full sized prototype. Insert nuts for those rails when used with 30x60 aluminum extrusion rails.
Ball screw kit parts for the full sized Z axis. 

I still haven't gotten the full sized ball screws for X and Y axes, and I need them to determine exactly how long the frame members and gantry beam need to be, as well as how to layout the frame end brackets. 
4D


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## 4DThinker (Feb 16, 2014)

I also have all the stepper motors I'll need. A set of NEMA 17 steppers previously used in a 1/4 scale CNC I made from old printer parts, and a set of NEMA 23 steppers that came with the X-Carve kit I bought a few years back that I gave up on for the belt drive strategy they used. These wood CNC prototypes will be more like what Probotix makes, and easily configured for vertical/angled clamping inside the frames. My 1/4 scale CNC had a fixed gantry/Z axis, and the bed moved beneath it in both X and Y directions. No vertical clamping potential there. 

4D


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## 4DThinker (Feb 16, 2014)

I realized I only have 3 nema 17 steppers from my previous small cnc project, and I'll need four to run the 1/2 scale prototype. I ordered another from amazon which should be here tomorrow. M8 nuts should show up today, so I'll likely cut a test pocket or two in some plywood scraps to sneak up on a good fit for the square M8 nut. These nuts will be inserted into the plywood beams so M8 bolts through end plates have some steel threads to screw into. I theory I can do the same thing on the 1/2 scale prototype using M4 bolts and square M4 nuts. 

4D


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## 4DThinker (Feb 16, 2014)

Test pockets cut for the M8 nuts. I had to cut them deeper than I expected. I assumed the 18mm and 12mm BB plywood glued together would be 30mm thick, but it is a bit thicker than that. That left the centered bolt holes a bit farther from the surface. I left the board on the CNC after cutting to check, then lowered Z0 by .02" a couple of times and recut the file until bolt and nut lined up. 

Once I'm actually assembling this CNC prototype I'll make some plugs to fill the nut pockets above the inserted nuts. 

4D


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## 4DThinker (Feb 16, 2014)

AARGH! I got home today to find a note on my front door that USPS had tried to deliver my large ball screws for the full sized CNC prototype. "Signature required". No ball screws today.


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## 4DThinker (Feb 16, 2014)

I picked up the ball screws at the local post office today. The parts were inside a cardboard tube, carefully entombed in bubble wrap and tape. The wrap, either the tube or the tape or the bubble wrap had a horrible stench to it. I had to quickly move it out of the house for fear the whole house would stink. All parts appear to have suffered no damage in the trip around the world. 

Next is to measure all the parts and lay out how/where to mount them on the frame rails/end plates. 

In addition the square M4 nuts for my 1/2 scale prototype also arrived. I've had to order a longer 1/16" end mill to be able to cut the pockets for them which I've drawn up in Aspire. 

4D


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## 4DThinker (Feb 16, 2014)

Well I'm glad I started with a plywood prototype. The mounting blocks for the ball screws are 60mm wide, taking up the whole height of the 3060 beams. No room left for the linear rails in the same plane. I'm going to switch to using 3090 beams (3 slots across the 90mm face) and mount the linear rails on the top 1/3 with the ball screws below that taking up the other 2/3. The bearing blocks don't stand off the same height as the ball screw block, so I plan to use 3/4 (18mm) BB plywood for the gantry risers and simply make a pocket so the taller ball screw block can be recessed into it. 

4D


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## 4DThinker (Feb 16, 2014)

Philosophically this plywood prototype was to be a test run for the final design of an aluminum extrusion framed CNC. Yet I can do things using plywood that I can't do with extrusions. I've already made the side beams thicker than the 3090 extrusions and a dimension that doesn't have an existing extrusion match. The mounting holes in the ball screw end brackets don't line up with any known t-slot layout. It is possible that by leaving the limitations of conventional extrusion based assemblies I can end up with a plywood design truly optimized for the plywood it is being made of. If my plywood version is stiff, square, and reliable it may be all I need. 

I'm still waiting on metric screws I've ordered which are coming from China. Two different orders haven't left China (as tracking indicates) for more than 3 weeks. I'm wondering is Trump's threatened import tariffs on steel and aluminum have China holding onto products made from either until all is settled politically. 

4D


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## RainMan 2.0 (May 6, 2014)

4DThinker said:


> Well I'm glad I started with a plywood prototype. The mounting blocks for the ball screws are 60mm wide, taking up the whole height of the 3060 beams. No room left for the linear rails in the same plane. I'm going to switch to using 3090 beams (3 slots across the 90mm face) and mount the linear rails on the top 1/3 with the ball screws below that taking up the other 2/3. The bearing blocks don't stand off the same height as the ball screw block, so I plan to use 3/4 (18mm) BB plywood for the gantry risers and simply make a pocket so the taller ball screw block can be recessed into it.
> 
> 4D


I love the way your approaching this ,as you can find and solve issues as you go .
As I mentioned, I was going to do something similar if I decided to scratch build one , but I suspect I’m going to take the easy road and buy one from CNCrouterparts.
It may save me a lot of headaches ,and not be much more cash seeing as I’ll have to deal with shipping from several vendors otherwise


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## 4DThinker (Feb 16, 2014)

It is easier to take my time on this CNC build project since I already have a working Probotix Meteor. The inspiration for making the smaller CNC came from the occasional situation where students wanted tenons cut on long stretchers that wouldn't fit standing up under the school's CNCs. The first did fit under my personal meteor as I made my stand a few inches taller than those. The latest request had me sticking a 4x4 post under the wheels of my Meteor to get the height needed. This small CNC will end up on a rack where I can raise or lower the bed height more easily. 

4D


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## 4DThinker (Feb 16, 2014)

I went on the hunt for some spacers to use for mounting the stepper motors yesterday. I needed some 1.375" long, with an inside hole that would slide over M5 bolts. I even tried to 3D print some but they would pop off the bed before they were anywhere close to being tall enough. I went to bed frustrated, but woke up with an idea to simply drill a 5mm hole though the center of some 3/8" wood dowel. I found some 3/8" diameter walnut and oak dowels in my scrap bin. So far I've succeeded in making 8 from the walnut to use with the Y axis motors. I cut the dowel into 1.375" long pieces, then pushed it into a snug 3/8" hole I had made at my drill press. The hole was clamped in place so it would stay centered under the bit. I changed to a #8 drill bit and for the most part it stayed close to the center of the dowel segments as I drilled through. 

Bolts for mounting the steppers won't be here until Wednesday. By then I should have the bed frame assembled with Y rails, ball screws, and steppers mounted. Then will come the gantry risers, followed by the gantry beam and Z axis assembly. This won't look like any CNC I've seen before when done. 

4D


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## 4DThinker (Feb 16, 2014)

End plates for the frame all laid out and cut. Frame joinery done and frame assembled. 1/8" shims made for the rear plates as I miscalculated how long the ball screw assembly was and the rear bracket sticks out past the frame .1" or so.

I'll have to abandon the terminal plates on the steppers as there is no place to mount them. I'll add on enough cable to reach the controller, and still be able to disconnect the steppers as their cables plug into them. 

The black piece in the middle is the router clamp from the X-Carve CNC I'm stealing the steppers from. I should be able to use it with this CNC. Screws to hold the end plates on I'll also pick up tomorrow.

4D


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## 4DThinker (Feb 16, 2014)

I'll add that I made the end plate tops to align with the top of the side beams. Depending on how I make the gantry risers I may be able to put a "top" on the side beams to cover and protect the rails and ball screw from chips and dust. 

4D


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## 4DThinker (Feb 16, 2014)

I got the steppers mounted to the end plates. I got the end plates bolted to the frame rail ends. I've got the couplers hooked up between the ball screw and the stepper shaft. Other than putting some finish on it and wiring it up the base frame and Y axis hardware is now complete. Phew. 

Now for the gantry risers.


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## RainMan 2.0 (May 6, 2014)

4DThinker said:


> I got the steppers mounted to the end plates. I got the end plates bolted to the frame rail ends. I've got the couplers hooked up between the ball screw and the stepper shaft. Other than putting some finish on it and wiring it up the base frame and Y axis hardware is now complete. Phew.
> 
> Now for the gantry risers.


This sounds like a cake walk :grin:


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## 4DThinker (Feb 16, 2014)

Possibly cake, but a complicated homemade cake. Not your normal cake from a box. 

Yesterday I must have had some food poisoning, but between **** I drew up and cut out plates to connect the ball screw flange brackets to the adjacent linear rail plate. Now when the Y steppers spin the gantry should move. Next is to connect the bearing plate upward to the gantry beam. For anyone curious I'm drawing up all the details in Aspire. Once I have a part isolated and done I copy it from the master file and paste it into a new file where I can create toolpaths and usually a duplicate or mirrored version. 

4D


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## BalloonEngineer (Mar 27, 2009)

This would have been a good task to try using Fusion 360. You could have imported pre-drawn items like the ballscrews, spindle and steppers from grabcad, put in your designed structure and then done all the toolpaths all in one file. It even has the entire McMaster Carr catalog integrated for things like the nuts and bolts. Being able to rotate and look at things from all angles helps figure out aspects such as clearances and tool access. 

Regardless, I have been following along with your progress and look forward to reading your comparison between this DIY and the other machines you use. I imagine having access to a CNC to build a CNC makes things much easier, and your experience using CNC ensures you can design in all the features that are most important to the kinds of work you do. Please continue to share your design thinking and problem solving as you go, it has been very informative.


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## 4DThinker (Feb 16, 2014)

I did download Fusion 360 and have played with it a bit. I am now quite familiar with Aspire though. I started using VCarve Pro when it was version 2.5 and Aspire when it was version 4.0. I don't have any trouble visualizing how 3D parts come together, no doubt from having helped students design furniture for the last 40ish years. Taking drafting for 3 years in a row while in high school, and getting 2 design degrees after that didn't hurt. 

The best problem solving strategy I ever learned was to break complex seemingly unsolvable challenges into bits that each are easily solvable. I have a big picture of how this whole CNC will look/work when done. Working on it literally from the ground up though I encounter then consider little questions that aren't obvious in the big picture. The linear rail bars, for example, have what looked to me like an arbitrary row of mounting holes in them, and an unknown resistance to bending. Although they are no doubt stiff enough if mounted flush using a screw in every hole, I realized I could sink them into a precision CNC cut 1/8" deep slot to eliminate any chance of bending, even if all the screws sheared off. Not a big picture consideration. A small optimization though. 

4D


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## 4DThinker (Feb 16, 2014)

I've drawn up and out the sides of the gantry risers. They slipped nicely into the mortises I'd cut in the bearing plates. Now I'm laying out where everything on the gantry needs to be so I can locate holes to fasten it and the stepper motor on the riser faces.

I've concluded the gantry linear rails need a simpler mounting to keep the total cantilever of the router as small as possible. No tilting of the gantry beam. I'm also aware of where chips and dust will land and am trying to put critical moving parts where most chips won't interfere with them. 

I'm also pondering where to mount the tinyG controller board. It needs 24vDC and a USB cable running to it, and runs out to all the stepper motors and limit switches. X and Z steppers are on the gantry. The X, Y, and Z limit switches can all be mounted on the gantry, I'm wondering for the most efficient cable layout if the tinyG itself shouldn't be mounted on the gantry. Perhaps inside a gantry riser. 

4D


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## BalloonEngineer (Mar 27, 2009)

On my machine, since it is rack and pinion drive for X and Y, I have all 4 steppers, all 3 home switches and even my VFD all mounted to the back side of the gantry. My ESS, gecko 540 stepper driver, and associated power supplies as well. I figured I would do it just as a trial, but it’s been working perfectly for two years now. No cable chains, short runs from stepper drivers to steppers, I like it. 



To reduce cantilever on the spindle (and increase stiffness) I separated the Z-axis rails and tucked the spindle in between them. The ballscrew is off to the side. My spindle (80mm dia, 2.2kw) centerline is less than 3 inches from the gantry.


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## 4DThinker (Feb 16, 2014)

Looks good B.E.. Running cables is now on my agenda, and after looking closely at my Probotix Meteor it is clear that their machines have thoughtful details on how cables are run and held in place. Holes in parts to run zip ties through along the paths, cables tucked into frame slots, etc.. I'm was going to worry about the cables after everything else was done but it is clear there is a benefit to working out the paths and hold down strategies as I go. As my frame is all plywood and so far only screwed together I can back up and take apart what I've done so far to add slots and holes for the cables to tuck into and pass through. Time to rethink, or addthink (my word) the project details. 

4D


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## 4DThinker (Feb 16, 2014)

I've got the gantry parts all figured out now. I drew up, made toolpaths for, and cut out the backplate for the router clamp, which itself screws into the linear rails and ball screw flange bracket. This plate will fasten to the front of the gantry beam surround which itself screws to the X axis linear rails. I've just verified that all the hole locations are in the right places. I should have a little over 6" of Z clearance when all is done. That will give me better access to parts clamped at an angle under the spindle. 

4D


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## Andy Lace (Apr 6, 2018)

*Cnc machine*

What is a cheap good cnc machine to buy. I had a look at a lot do not know what to buy this be my frist one.


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## 4DThinker (Feb 16, 2014)

Before settling on a CNC, consider what you want one for. Then let that help you decide on how big of a machine you'll need. Depending on the machine, much more may be possible than what you've imagined one can do. Where I work we have a huge machine with a 5' x 10' vacuum bed which cranks out parts cut from plywood and other sheet goods all day long. We have a small CNC shark, which has pretty good Z clearance an primarily cuts out small 3D furniture parts that can fit within its 25" x 25" t-track cutting area. We have a 25 x 50 Probotix meteor and a 37 x 50 Probotix Nebula as well. The Nebula has a 4th axis on one side, and an open area next to a flat t-track area for rotary cuts, vertical joinery cuts and flat cuts. The Meteor has an adjustable angle clamping jig on the front half and handles angled and compound angle cuts on assorted furniture parts. 

I have access to all of those, and yet I'm making a CNC that will do something nearly impossible to do with any of those. It will be mounted on a sliding height-adjustable rack, so I can slide it up to the ceiling if need be to clamp long sofa or bed stretchers under it for cutting tenons on their ends. 

So knowing what you want to make will help us know what machine to recommend. You might throw out a budget limit too. The last 4 machines I described are all available for less that $5k. That big monster was a $90k investment. 

4D


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## Andy Lace (Apr 6, 2018)

This will be my frist one so I was thinking some thing £400-700 not idea what I cut on it yet. Just see how it goes.


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## 4DThinker (Feb 16, 2014)

You won't find much in your price range besides a few Chinese CNCs that you can find on ebay, or a kit.


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## Andy Lace (Apr 6, 2018)

I look at a x carve cnc think I get one of them


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## Andy Lace (Apr 6, 2018)

Just trying to found out if it will do 3d


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## 4DThinker (Feb 16, 2014)

It should have no trouble doing 3D cuts so long as the software you use to generate toolpaths can do 3D toolpaths. 

4D


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## Andy Lace (Apr 6, 2018)

Ok thanks


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## 4DThinker (Feb 16, 2014)

Just a quick update on the progress of my plywood CNC prototype. The semester has been a busy one, but I've been chipping away at all the details as time permitted. All that is left to do is to mount the limit switches, run all the cables, then power up this critter. All the construction is done. I'll make sure it runs, is true and square to the cutting plane, then likely take it apart again to put a finish on all the parts.


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## BalloonEngineer (Mar 27, 2009)

Very nice! Did you have much trouble getting the profile rails aligned? Have not seen them mounted in two planes like that before, and I understand that they need to be very precisely aligned. Looking forward to seeing it running.


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## 4DThinker (Feb 16, 2014)

BalloonEngineer said:


> Did you have much trouble getting the profile rails aligned?


As all the parts were cut on my Probotix CNC the alignment relied on front and back rails being identical. They are. The X axis also has two rails that are not in the same plane, and it glides smoothly from side to side. One rail on top of the gantry beam, and the other embedded into the front face of the beam.

4D


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## UglySign (Nov 17, 2015)

That looks wicked 4D. Man... that would be a neat project.
I just dont have that patience. Good Job!

Put a little piece of Walnut on there for David. :wink:



4DThinker said:


> Just a quick update on the progress of my plywood CNC prototype. The semester has been a busy one, but I've been chipping away at all the details as time permitted. All that is left to do is to mount the limit switches, run all the cables, then power up this critter. All the construction is done. I'll make sure it runs, is true and square to the cutting plane, then likely take it apart again to put a finish on all the parts.


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## 4DThinker (Feb 16, 2014)

The front of the gantry beam is clear of any hardware, and for awhile I was thinking about inlaying something into it. Probotix posted a photo of one of their CNCs with their logo and machine name on the front of the gantry. I was considering "4D2-1818" as I've got 18" x 18" of X/Y travel and this is my second original plywood CNC design. Every rendering I did just looked distracting to me though, so I've abandoned that idea. 

4D


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## UglySign (Nov 17, 2015)

4DThinker said:


> The front of the gantry beam is clear of any hardware, and for awhile I was thinking about inlaying something into it. Probotix posted a photo of one of their CNCs with their logo and machine name on the front of the gantry. I was considering "4D2-1818" as I've got 18" x 18" of X/Y travel and this is my second original plywood CNC design. Every rendering I did just looked distracting to me though, so I've abandoned that idea.
> 4D


Oh I dig.... actually looks like phone #. How about "Eat at Joe's"
People wouldnt know what direction to go, either wondering about Joe's
or watching the action in the cut.


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## 4DThinker (Feb 16, 2014)

Well, I've finally got my plywood CNC wired up to my tinyG controller. So far it works, and it doesn't. I get accurate motion with my left Y axis stepper and the Z axis stepper. The right Y axis stepper doesn't budge. The X axis stepper tries to move but binds and whistles to complain. I'm using TGFX (now discontinued) as I don't have an internet connection where the CNC is. I checked for continuity on all the cables from tinyG to steppers and all appears connected. 

Anyone out have experience using the tinyG? I find conflicting info on whether two different drivers can be mapped to Y. I've got X on motor one, my left Y stepper on motor two, right Y stepper on motor 3, and Z stepper on motor 4. 

4D


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## 4DThinker (Feb 16, 2014)

OK, now I've got get the right Y stepper moving, although it is losing steps occasionally. I had to reseat the connector to it. I believe I may need a larger cable to it as the current one is unshielded and of a small gauge than what the other steppers are using. 

The X axis stepper that moves the Z axis assembly back and forth is still a puzzle. It does not take much force to move the assembly left or right. Far less than moving the whole gantry back and forth. That stepper just stutters, and only moves in one direction no matter which direction key I'm pressing. It has a relatively short shielded cable between it and the tinyG. Short than the one for the Z axis which works fine. I'm starting to think the stepper is defective. When the motor is OFF I can easily turn the shaft by the coupler, so there is not much rotational resistance. 

4D


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## beltramidave (Jan 6, 2016)

Have you tried swapping x and z cables?


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## 4DThinker (Feb 16, 2014)

A good idea Dave. Once I get some enthusiasm to go back and try again I'll do that. I can't swap cables at the motor end, but I can swap where each connects at the tinyG. If the stuttering moves to the Z stepper and the X stepper starts to work OK, then it'll imply one driver output on the tinyG may need different settings or is defective. If both start working then it may end up being an iffy connection at the tinyG. 

It has been a long time since I initially bought the tinyG Controller. Originally I only used 3 of the 4 stepper outputs, so it is possible one was left in an "off" state or somehow unconfigured. It would have been either the 1st (now X) or the last (now Z).


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## beltramidave (Jan 6, 2016)

Was just a guess, as I know nothing of the Tiny G other than what I just watched in this video. Maybe check the current setting on the driver first.






Dave


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## 4DThinker (Feb 16, 2014)

I swapped the X and Z cables at the tinyG end, and then remapped the ports in TGFX. The problem is the #1 motor port on the tinyG. I now have a working X axis but the Z axis stepper is doing what the X axis stepper used to do. That rules out the stepper motors, as well as the cables running to them. I can get both Y steppers to run the same so long as they are jogging slowly. I figure a new thicker cable will fix that problem for good and I've already ordered some. 

I'll have to dig into the board settings for the #1 motor port. Having swapped the cables per your suggestion at least gives me hope that this CNC won't need a new stepper. 

4D


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## 4DThinker (Feb 16, 2014)

No matter what I try, the #1 motor port on my old tinyG is not cooperating. I've ordered a new tinyG which should arrive early next week. I'll keep this tinyG as I have no doubt I can use the 3 working motor outputs for some future project. 

I'm currently working on a way to automate setting the angle on my adjustable angle jig. I want to have a simple input or dial to pick the angle I want, then a button to press (or a dial I can press in) to make the jig move to and lock into that position. I can figure out the mechanics of it, but simplifying the input part of controlling one stepper motor is where my struggle lies. 

4D


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## beltramidave (Jan 6, 2016)

Just thinking out load here and coming from a Linuxcnc background, I don't know if you can do something similar.

For initial setup, could you use a Wixey gauge (or something similar) to drive your jig to the correct angle by using your jog buttons. Then note the actual machine position coordinate for that angle and then create basic MDI commands based on that. In Linuxcnc, you could create MDI interface buttons tied to those angles.

Dave


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## 4DThinker (Feb 16, 2014)

beltramidave said:


> For initial setup, could you use a Wixey gauge (or something similar) to drive your jig to the correct angle by using your jog buttons. Then note the actual machine position coordinate for that angle and then create basic MDI commands based on that. In Linuxcnc, you could create MDI interface buttons tied to those angles.
> 
> Dave


I already use a Wixey gauge to set the jig, but when the angle needs to be a fraction of a degree it is finicky. A little shake of the CNC bed and the value jumps around. I don't need/plan to do this inside LinuxCNC. I just want a simple input place on or near the jig that I can set a value, then know the jig will adjust to and lock into that angle. I can adjust the angle on a prototype jig with a simple hand crank to creep up on the angle I want, but with the Wixey gauge as the reference even the spin of the handle wiggles the value it shows. Ideally I want to zero the jig when it is bottomed out and vertical. Then dial in or type in the angle I want and have a stepper (rather than a crank) spin the jig to that angle. I might even use two slaved steppers to move the jig evenly up and down as there is a little sideways play with just one hand crank. My old tinyG could spin the steppers, but rather than using a PC to run it I want to use just a simply dial with a small LCD screen to read out the angle. Analogue signal from the dial/potentiometer, mapped to a degree from 0 (horizontal) to 90 (vertical). Then a push button signal to initiate the movement of the jig.

This would make the jig something anyone with an open frame could install and use. 

4D


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## 4DThinker (Feb 16, 2014)

For my adjustable angle jig I've ordered an arduino "kit". It looks like a little programming of the arduino and the bits the kit includes and I may have all the parts to make a prototype of the digitally adjustable jig. Hopefully this old dog can learn a few new tricks yet. 

4D


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## beltramidave (Jan 6, 2016)

4DThinker said:


> For my adjustable angle jig I've ordered an arduino "kit". It looks like a little programming of the arduino and the bits the kit includes and I may have all the parts to make a prototype of the digitally adjustable jig. Hopefully this old dog can learn a few new tricks yet.
> 
> 4D


Interested to see how this goes.


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## 4DThinker (Feb 16, 2014)

The kit will arrive tomorrow. I've already downloaded the Arduino IDE (programming app). Many years ago I was a pretty good BASIC programmer, but that seems like 5 lives ago. Nothing I've seen so far looks too challenging though. I'll post my progress here. 

4D


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## 4DThinker (Feb 16, 2014)

Both the arduino kit and the new tinyG came today at around noon. I spent the afternoon installing and configuring the new tinyG. All the steppers now work, and the X and Z axis seem reliable so long as I don't set the jog rate too fast (200ipm works fine on the X axis, 60ipm on the Z). The two Y steppers stay aligned when creeping along at 10ipm, but one or the other will inevitably stall, causing the gantry to rack at 100ipm or faster. Moving the whole gantry is the biggest challenge. When detached from the ball screw brackets it is fairly easy for me to move on the linear rails. Spinning the ball screws is likely where the load is. I'm thinking these steppers may just not be up to the task, in which case I'm not sure what to do. The tinyG isn't designed to drive steppers drawing anything more the 2.5a, and that's what these are rated at. 

I've been looking at the clearpath servos, and apparently they can be driven from the tinyG but have their own power supply. They are pricey, but "smart" enough to keep in step. I'd invest in a pair just to move the Y axis if I wasn't afraid their "autotune" routine wouldn't quake my CNC apart. 

I'll be playing with the arduino kit tonight and tomorrow. 

4D


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## BalloonEngineer (Mar 27, 2009)

Time for some updated pictures! I am not familiar with the tinyG, would love to see how everything is working.


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## 4DThinker (Feb 16, 2014)

Before I commit to buying the clearpath servos to run my Y axis I've order 2 larger nema 23 steppers that have a higher (3x times) torque rating than the ones I have. They should show up on Friday. By their specs the tinyG should still be to drive them. If they run the Y axis fine I may get 2 more to replace the X and Z steppers just to be sure I don't run into any lost steps when actually cutting parts.

In the meantime I've drawn parts for a drop-in t-slotted bed. I have enough materials laying around and that'll give me a way to hold down some scraps to do some test cuts to verify square and plum and precise. 

4D


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## 4DThinker (Feb 16, 2014)

Whew. The new larger (with more torque) steppers arrived today and my dual Y axis now works. I ran a few files with no router attached and the X axis slipped a couple of times, so it is getting a large stepper too. I ordered two more so I'll update the Z axis as well. Once a router is attached the increased load will appreciate the larger steppers. 

I'm impressed that the tinyG has the ability to run this machine. Quite a feat of engineering the designers did. The tgfx software leaves much to be desired though. I'll be looking into chillipepper/tinyG (a web app) to run it, but I'm suspicious of web-based controllers that require uploading your g-code to some server on the web. 

I'd love to be able to run this CNC with linuxCNC, but it has no support for the tinyG over USB. 

4D


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