# Beginner in CNC trying to decide on number of axes



## doc7347 (May 15, 2017)

Hello, everybody.

I'm a hobbyist with a particular taste for DIY projects, customisation and general tinkering. About a year ago I bought a 3D printer and have loved it ever since - I can produce little items that I can't buy anywhere, it's cheap and pretty much imagination is the limit. I have had my taste of 3D printing and as awesome as it is it has its own limitations, mainly in the materials the process uses. I want to upgrade to a CNC router and to be able to machine items out of materials like wood and aluminium and maybe steel, but I realise that this is a whole new level.

I'm searching for a unit that will be able to machine items that I design in three dimensions. I'm willing to buy a kit but I would prefer to assemble one myself (I'm assuming it won't be too challenging for me as I have built couple of 3D printers from scratch). I did a bit of a research and found out what 3-axis routers are capable of (pretty much 2D items and quite simple 3D ones) and I don't think this will be enough for my needs. I also looked into 4-axes and 5-axes routers and I believe that this will cover what I want to do. I, however, have doubts that 4-axes will be sufficient and that 5-axes will be too elaborate of a project. I realise that a small amount of after processing will be required but this won't be a problem.

I'd appreciate if someone more knowledgeable was to clarify things a bit for me.

Best


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## difalkner (Jan 3, 2012)

Welcome to the forum, Doc! 

What's your budget and available space like for this machine? I'm not aware of any kits with more than 3 axes but I also haven't looked for any in this form. 

David


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## doc7347 (May 15, 2017)

Thank you, for the warm welcoming, David!

I'm willing to spend no more than $10 000. I haven't thought about space restrictions but maybe 2m*1m*1m.


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## difalkner (Jan 3, 2012)

Does that include space to walk around the machine or is that just for the machine itself? Our machine is a Saturn 2x4 but the footprint is about 54" x 70", so you can add at least 15" or so to that for walking around the machine.

David


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## doc7347 (May 15, 2017)

I do remember saying 2m*1m*1m but I don't think I had a clear understanding what that means until I googled it.
Thanks for mentioning the Saturn 2x4 - looks utterly beautiful!

I think it's fair to say that for my first project usable area of 0.5m*0.3m*0.3m to 1m*0.5m*0.5m will suffice.


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## MikeMa (Jul 27, 2006)

Your hobbyist oriented machines (under $10k) are typically going to be 3 or 4 axis, or the 4th axis is for turnings. For CNCs where they have a axis that pivot and turn the spindle, this adds considerable complexity and cost, typically seen in more industrial applications. For what you are looking for, you probably are going to need look at the bigger industrial machines.


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## doc7347 (May 15, 2017)

@MikeMa
If I were to hop into the industrial machines segment what price and footprint am I looking at?
@difalkner
I noticed that the Saturn is a 3-axis machine. I'm worried that a 3-axis router won't be able to machine fairly complex 3D items. I could rotate the piece of material so the spindle can access a different part but I'm worried that if I did that by hand I would mess up the orientation of the item. If another (4th) axis was to make that movement for me I would feel better but wouldn't that be more complicated in terms of software?


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## RainMan 2.0 (May 6, 2014)

Kinda small , but kind of neat at the same time . Check there video out 

https://www.kickstarter.com/projects/1090944145/pocket-nc-the-first-5-axis-cnc-mill-for-your-deskt


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## difalkner (Jan 3, 2012)

doc7347 said:


> @MikeMa
> If I were to hop into the industrial machines segment what price and footprint am I looking at?
> @difalkner
> I noticed that the Saturn is a 3-axis machine. I'm worried that a 3-axis router won't be able to machine fairly complex 3D items. I could rotate the piece of material so the spindle can access a different part but I'm worried that if I did that by hand I would mess up the orientation of the item. If another (4th) axis was to make that movement for me I would feel better but wouldn't that be more complicated in terms of software?


The 4th axis is generally used for turning but it can also be used for indexing. So you can mount a piece on the 4th axis, cut what you can get to with XYZ movement, then index the piece and cut some more. That movement is generated by your CAM module of whatever software you use and then the controller software, Mach3/4 for instance, interpolates that toolpath into machine movement. 

So the quick answer is 'yes', it does make it more complicated but not impossible. It sounds like what you're cutting requires that sort of movement so it isn't really that complicated, just another step you learn in the process. And you won't be reinventing the wheel - this has been done thousands of times and there are probably many tutorials and videos that will show you what you want. 

I intend to add a 4th axis one day soon for this very purpose - indexing, rotating 3D pieces, and turning. Don't wait on me for a video, though; I'm not in a hurry. LOL!

David


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## doc7347 (May 15, 2017)

@RainMan 2.0
Thanks for linking that. I did see while I was researching and is quite spot on what I need BUT it's too small for my applications. That's why I started looking towards 3/4-axis "conventional"(?) routers.
@difalkner



difalkner said:


> So the quick answer is 'yes', it does make it more complicated but not impossible. It sounds like what you're cutting requires that sort of movement so it isn't really that complicated, just another step you learn in the process. And you won't be reinventing the wheel - this has been done thousands of times and there are probably many tutorials and videos that will show you what you want.


This is exactly what I'm in the market for...or at least to the best of my knowledge at the moment, haha.
Could you tell me more about such setup? Given I'm new to this I'm not sure what questions to ask but if I had a starting point I could word a smart question.


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## difalkner (Jan 3, 2012)

Just a quick Google search will get you a ton of info, but you can start here - CNC 4th Axis Basics

David


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## mark greenbaum (Sep 26, 2010)

I used a small desktop (precision) CNC, 4 axis for the jewelry industry. I carve master waxes, flat, flip, the rotary. Then I cast the master waxes and it was so precise I only have to lightly buff the casting, and cut seats for the diamonds, and push prongs. The accuracy was defines by the cutter, toolpath, and software to convert stl files to machine code for that particular setup.


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## Tagwatts (Apr 11, 2012)

doc7347,
The CNC Equipment you are talking about and amount of money you are willing to spend, you need to step away from the hobby type CNC and look right into the industrial models. The size is going to be an issue you will have to consider. I do not know of any kits on the market of the nature you are wanting to build that will meet your needs. Building your own will work if you have the knowledge and talent. 

The next item you need to consider when wanting to use as many axis as you have mentioned is going to be pretty expensive and will be very in depth. If I were you, I would go into some shops that already use the type of machines you are looking at and get advice from those who are professional at what they do. Nothing against hobbies-ts, but we do not have the know how and do not work with the software or spend the time trying to make a living with the CNC. I am sure if you look into this a little more you will havea much clearer idea of what it is exactly you need and want. Good Luck, Tagwatts


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## MEBCWD (Jan 14, 2012)

No one has ask what kind of projects you actually want to make. That might make it easier to determine what you actually need. 

If you are using Vectric Aspire or VCarve Pro you can design projects to be cut on a 4th Axis machine by wrapping the design around a cylinder then the output toolpath rotates the blank as it is cut.

I don't think you will find a 5th Axis machine for the money you have to spend and a 4th axis might be all you need.


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## honesttjohn (Feb 17, 2015)

He sure seems to want to take a pretty big bite as a beginner. Got to have more smarts than I'll ever have doing this.

You guys are right - he's going to have to step up to the "pro" stuff and get a bigger checkbook. Or.......he could just kidnap David, get a parts list, and not release him til it's up and running.


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## doc7347 (May 15, 2017)

@difalkner
Thanks, I will go at it from there.
@mark greenbaum
What you have described is not too far from what I will be dealing with as complexity. I will only need slightly bigger work envelope than you do, based on your post.
@Tagwatts
Thanks for being blunt, I'm not sure what I need/want myself. Based on some new info I found, I believe 3-axis machine will be enough for what I want to do, but I'm still researching. I'm still hesitant to lean towards full scale industrial level machine - I'm just not sure I will be utilising its full potential. Maybe I'm so confused, I'm confusing even you guys, eh.
When I stated my budget that was the absolute highest I can go. I did the same thing when I bought my 3D printer. I allocated 2 000 for it and ended up paying 800. That's me, I guess. I shiver in horror with the thought of not spending another 200-500 bucks and not getting the actually good machine that I want and can afford. Hope that makes sense.
@MEBCWD
Initially, I wanted to go for a 4-axis machine because I was worried I wouldn't be able to rotate the model properly and machine all sides in the right planes. After some research I found out that I can do that with a 3-axis router and vices. You, quite mindfully, asked what projects I want to machine. The answer is that I don't know but I want a fair bit of versatility. I want to be able to make something out of aluminium for my car, something out of wood for home comfort etc. Hope this gives you a clue.
@honesttjohn
Don't give me ideas, mate, I might just listen to you, lol.


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## MEBCWD (Jan 14, 2012)

If you look at 5 axis machines the size you are talking about you will probably find that they start at about 3 times your budget and that is just for the machine, most require you to buy the design and cam software and 5 axis software is not cheap. 

I think you may be underestimating the abilities of a 3 axis machine. Adding a 4th axis is not too costly just make sure you start with a control unit that can be upgraded to the 4th axis. You will be limited in the size of a 4th axis project but it all depends on the machine you buy.

Like I said before Vectric Aspire and VCarve Pro (included with some machines) will allow you to design wrapped projects for the 4th axis and output toolpaths. There are other design softwares that allow you to design for a 4th axis project, that will just depend on the projects you want to do.


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## MikeMa (Jul 27, 2006)

doc7347 said:


> @MikeMa
> If I were to hop into the industrial machines segment what price and footprint am I looking at?


Honestly, I do not know. I have been researching and started collect parts for building my own 3 axis CNC. I just know that once you get beyond the standard 3, each new axis adds a degree of complexity both for hardward and software. If I recall you budget was $10k. I can see an industrial machine very quickly surpassing that budget. I suspect most companies that order a CNC have it spec'd and custom made to their needs. They aren't boxed units like you would get at Woodcraft or Rockler. Not to mention there will be some degree of education (not necessarily free) required to learn how to use those machines.

Using a 3 axis CNC, there are some techniques to get accomplish, with precision, to do 3D carvings. There are tutorials out there on how to do that. Since you are just getting started my recommendation is look at one of the higher end (with fully supported rails) CNC machines with the standard 3 axis, with maybe a 4th turning axis on it. Learn to use that, and figure out ways to use it for what you need.


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## MT Stringer (Aug 15, 2012)

Check out Craigslist for prices. That should give you some in site on what you are dealing with. Here is our local Craigslist (Houston) items for sale today.
https://houston.craigslist.org/search/sss?query=cnc&sort=rel

I don't know what some of those machines are, but the prices jump to $30K quickly!


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## doc7347 (May 15, 2017)

MikeMa said:


> look at one of the higher end (with fully supported rails) CNC machines with the standard 3 axis


I think I know what a 3-axis router looks like but I'd appreciate if you were to link a picture or a machine that has these "fully supported rails"

Also, I do get the strong feeling that my first machine will be something in the hobbyist segment. I was looking at the Openbuilds OX and such design looks like a promising start to me.


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## 4DThinker (Feb 16, 2014)

If you can't afford a true 5-axis CNC, then the next best thing is a 3-axis CNC with the ability to clamp parts below it at any angle relative to the X/Y cutting plane. We cut very complicated parts using one of Probotix.com's CNCs and an adjustable angle clamping fixture that fits into the bed frame. Their machines aren't quite stiff enough for milling hard metals, but can handle any wood and most plastics/composite materials. Soft metals are possible if you choose a programmable spindle and look into bits optimized for cutting metal. 

3D work is possible less undercuts if all the surfaces can be reached from the top. Clamp where you can cut one side then re-position/re-clamp to access/cut another. We've made much more complicated 3D parts by splitting the 3D model apart to cut reachable faces, then gluing the finished sections together to make the whole finished part. These have include parts that couldn't have been cut easier with a 5-axis CNC. 

4D


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## difalkner (Jan 3, 2012)

doc7347 said:


> I think I know what a 3-axis router looks like but I'd appreciate if you were to link a picture or a machine that has these "fully supported rails"
> 
> Also, I do get the strong feeling that my first machine will be something in the hobbyist segment. I was looking at the Openbuilds OX and such design looks like a promising start to me.


Here's our build in detail if you want to check it out (spent less than $10k, btw) - 2nd Build First

David


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## BalloonEngineer (Mar 27, 2009)

To see a rotary axis in use, try looking on YouTube for "Legacy Maverick". I have several friends who have this machine and it comes with a rotary axis standard (but its a $16,000 machine). Some of the Probotix machines also can be ordered with a rotary axis.

Both of these options are too much $ for me. I will be repurposing a mini-lathe into the rotary axis on my DIY cnc router. Got most of it planned out, but will probably not be building for a couple of months yet. 

There is a lot you can do with 3 axis, especially with some creative fixtureing to machine from both sides or by changing the angle of the workpiece.


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## Stick486 (Jan 4, 2013)

difalkner said:


> Here's our build in detail if you want to check it out (spent less than $10k, btw) - 2nd Build First
> 
> David


that was a build to behold...


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## MikeMa (Jul 27, 2006)

doc7347 said:


> I think I know what a 3-axis router looks like but I'd appreciate if you were to link a picture or a machine that has these "fully supported rails"
> 
> Also, I do get the strong feeling that my first machine will be something in the hobbyist segment. I was looking at the Openbuilds OX and such design looks like a promising start to me.


I am using SBR20 rails for my CNC build, which is an example of full supported rails. Many of the hobby machines have round tube rails that are only supported on the ends. While they look beefy, they actually have a lot of flex to them, which results in slower operation. The rigidity of the machine itself has just as much to do with the overall speed of the machine as do the stepper motors.

I took a look at the Openbuild OX, and would consider it a light weight machine, similar to the X-Carve or Shapeoko. For me another detractor is the Arduino GRBL interface. While that is a common setup for 3D Printers, it can be limiting in the CNC Router world. Since GRBL is typically limited to running motors to 2-2.5amps, that likely means running a motor smaller than 200oz/in. For my machine, I am looking at a MINIMUM of 400oz/in. One last thing I don't like about those smaller "kit" machines is that they are built driven rather than a lead screw or rack and pinion. The belts can flex, and if you keep it in a garage where climate control can be nonexistent, the tension can vary based on temperature.

If it helps, the machine I am building will be approximately 25" capacity X, 18" capacity Y, and 5.75" capacity Z. I would have gone bigger, but my shop space is limited. All three axis will be using the SBR20 rails as I mentioned above. The gantry will be made using 8020 (30-Series) extruded aluminum. Working with a friend who had designed and built his first CNC (and working on his second), I drew up my own plans for my CNC. I will be running LinuxCNC as the controller software, and running a parallel port based controller board (known as a Breakout Board).


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## doc7347 (May 15, 2017)

@MikeMa
Thanks for the input. Does give me some more clarity.

Did some more research and made a different decision. I'm buying my first router and when I know what's what, I'll build another one, properly. I did this with my 3D printer and enjoyed the process and the outcome. I'm considering the OmioCNC X6 2200 USB, sorry can't post the link. What are your thoughts on that?


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## Ottobidago (Apr 25, 2017)

Go to CNCrouterparts.com and look at their "PRO" series. You can get the axis's that you want in a great machine at less that $10,000. You can upgrade it there with spindles and electronics and still be within your budget. This is a kit.


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## doc7347 (May 15, 2017)

Ottobidago said:


> Go to CNCrouterparts.com and look at their "PRO" series. You can get the axis's that you want in a great machine at less that $10,000. You can upgrade it there with spindles and electronics and still be within your budget. This is a kit.


Did see these. Trouble is I'm on the other side of the pond.


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## RainMan 2.0 (May 6, 2014)

Ottobidago, welcome to the forum. Although I don't own one yet , after a lot of research , I'm a big fan of CNCrouterparts


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## Mark e (Jun 6, 2014)

You never said how big you need to go as far as I can see but a handibot with a 4th axis add-on will set you back less than 5K.

If you don't have prior experience don't expect to use that 4th axis the first few months.


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## SteveMI (May 29, 2011)

Beyond the physical machine, software to create the true 4 axis or 5 axis cutting path is specialized and could eat your entire budget. Rhino CAM Professional can do 4 axis, but one seat of the software is $6,000 (list price). Rhino CAM Premium can do 5 axis, but one seat of the software is $10,000 (list price). Plus you have to have the Rhino CAD software at $1,000 (list price) to start with since Rhino CAM is a plugin. 

Fusion 360 has it on the long term plan, but will not be in the free or base version.

Steve.


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## SteveMI (May 29, 2011)

As to the machine, I remembered seeing something and went back to some notes. Look at this site for plans;
Plans to build your own 5 axis machine ? Doughty Drive
On that site are examples of 5 axis that shows rotating a part is not fully the same potential;
DD100 ? Doughty Drive
B/C Drive ? Doughty Drive

The site also has recommended CAM software at;
Helpful information ? Doughty Drive

One of the packages madCAM is $6,000 plus Rhino3D

Steve.


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## difalkner (Jan 3, 2012)

I believe Fusion 360 supports 4th axis now, Steve. In the CAM module it is called 'Wrap Toolpath' (2D Adaptive Clearing and 2D Contour). It came out in November 2016. While I don't have a 4th axis I just drew a simple cylinder and cut pockets around the perimeter in simulation and it worked just fine. Odd, but the simulation moves the tool around the work piece instead of rotating the work.

Here's a video - 




David


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