# Probotix CNCs, Square and Plumb



## 4DThinker (Feb 16, 2014)

Don't take this the wrong way.... I love the CNCs made by Probotix. We have a Meteor where I work though which has always been reliable... except when precision of detail alignment or dimension has been a critical factor.

I've lately been perplexed more than usual on why joinery cuts on my vertical clamping jig have been misaligned. Over the Thanksgiving break (9 days when no students were on campus) I decided to get to the bottom of the mystery.

With squares and precision measuring rules I went at this old Meteor. My findings surprised me, but do explain why so often over the last several years I've been dissatisfied by the results of a cut. 

1. The Z axis assembly was not square to the frame or X/Y travel plane. Tilted back roughly 2 degrees.
2. The gantry wasn't parallel to the front/back frame members. Approx. 1/16" back on the right side compared to the left side. 

The gantry alignment is set when homing. Limit switches on the right and left hit a triangular bracket screwed to the bottom of the side frame members. In this meteor the bracket on the right was 1/16" farther back than the one on the left. A relatively easy fix, but also should have been easy to set right at the factory. 

The only way I can see to square the Z axis assembly is to rotate the gantry beam. Two bolts on each side hold the beam to the vertical side plates. These bolts go through holes in the side plates with no obvious slop in the fit. The solution I see is to remove the two front bolts, ream out the holes they went through, crank the whole beam/Z axis forward until plumb then insert and tighten those two bolts. 

I also have a Meteor in my home shop, and it does not suffer the same flaws this work machine does. My Z axis is plumb. My gantry runs parallel to my front frame rail. 

My point here is to check any new machine for plumb and square. In most cases flaws found can be corrected, and the accuracy of your work will increase. 

4D


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## RainMan 2.0 (May 6, 2014)

Is there a chance the gantry amd machine got tweaked a little as a student had the router forced against a piece of wood or something, putting to much strain on the gantry as it was trying to move ?


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## 4DThinker (Feb 16, 2014)

Our college went through a remodel that took essentially 3 years. The CNCs went through 4 moves as we were first kicked out of our original shop are so asbestos was removed and that area was turned into a large lecture room. We moved into a basement area in the old building first. Then a move to a temporary wearhouse while we waited for a temporary metal shop building to be erected near the temporary classroom building, then finally back into our new shop space. It is quite possible the Probotix CNCs were lifted by a crane using straps around the gantry which may have twisted the gantry. I personally didn't witness how they were moved any of the 4 times. 

I've had the Z axis come down on immovable clamps a few times, which certainly puts unusual forces on the Z axis assembly and gantry. On inspection though I can't see any way things could have been rotated or twisted to a new position and stayed there, as I can't see any bent/damaged parts in the assembly. There is also no apparent way to adjust the rotation of the Z assembly around the beam, or the rotation of the beam itself relative to the side brackets. 

4D


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## difalkner (Jan 3, 2012)

I know you're glad to have it all lined up and like it should be.

Our Saturn gantry was out of square by about 1/8". Someone suggested I use homing to square the gantry but I would never want to do that. I'd rather have the gantry *mechanically *square than to force it square with electronics. And the Saturn is so rigid I doubt it could even be pulled square by the electronics. So now it's square, the gantry glides easily along the linear rails, and it cuts as it should. But it was out for the first year I ran it because I didn't realize it was out. When I fixed it all sorts of things I cut in the past began working much, much better.

David


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## MEBCWD (Jan 14, 2012)

It is a good idea to check the alignment of your machine at least every 6 months just to make sure something hasn't changed. Just a little wear in parts will affect the alignment and quality of projects. It also lets you know when parts are failing before something major happens.

In the last year I have been getting questions on how to align the Y axis to the X axis on the Next Wave Automation CNC Shark machines. They should be aligned before they leave the factory as far as I'm concerned. When I tell them what they have to go through a couple have said they contacted Next Wave Automation customer service about the problem and they told them the same thing about aligning the machine. They were hoping there would be an easy fix but you have to remove the bed so you can get to the Y axis mount to the gantry, make adjustments then reinstall the bed and recheck alignment. Then repeat if it is still off a little. 

I have considered making aftermarket upgrade kits that would allow you to make easier adjustments for aligning their CNC's but I'm trying to get away from their machines and problems just like this.

I do maintenance calls on their machines and this is one problem I will not address, too involved and time-consuming to quote a price because of what you have to do to re-align and check to make sure everything is correct.


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## Pro4824 (Oct 17, 2015)

I bolted mine together, wired it up and started cutting. I either got lucky or my old eyes are too bad to see the misalignment issues. Someday I will run the cncrp alignment tests and adjust if necessary but for now I'm pretty happy being lucky or blind. 🙂


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## 4DThinker (Feb 16, 2014)

We have an old NextWave Automation Shark HD in the same room as our Nebula and Meteor from Probotix. It was our first CNC, and was heavily used until the Meteor showed up. The plastic Z axis design of the Shark has so much flex that I've essentially stopped using that machine. We just ordered a Comet from Probotix (10% off sale right now) to take its place, and the Shark will be sold. My little CNC room will now be a Probotix-only room. As they've raised and stiffened the gantry of their designs, the little Comet should now do all that the Shark was used for (extra Z height) and with my angle jig in it should do all the complicated joinery I cut as well. I'll mount it on a taller base to handle the vertical joinery cuts on long(er) stretchers and furniture panels. 

The Comet will be thoroughly inspected for square and plumb once it arrives. 
4D


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## 4DThinker (Feb 16, 2014)

Today we received our new Probotix Comet. Uncrated, set up temporary on a workbench to mount the Z axis stepper and install the Y axis limit switches. A quick check of the Z axis shows it isn't 90 degrees to the bed. It appears the cantilevered weight has racked the whole gantry beam a couple of degrees forward. 

We aren't quite sure how to remedy this. It was freezing cold today and the CNC parts were icy cold, so I'm going to let it acclimate to the warm shop overnight before final judgement and photos to send to Probotix. It may be possible that the bitter cold "shrank" the gantry risers which caused them to twist a bit based on how they are mounted/restricted by bearings and beam. 

I'll admit I do like the improvements they've done to stiffen up the gantry/Z axis. The added Z travel will come in very handy. 

4D


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## difalkner (Jan 3, 2012)

You are going to post photos, right?

David


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## honesttjohn (Feb 17, 2015)

Right now Probotix has a 4 day sale starting --- 20% off.


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## 4DThinker (Feb 16, 2014)

True that is John. Very tempted to buy something.... anything from them just to save that 20%! Of course I don't actually need anything they have, but ...~!


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## 4DThinker (Feb 16, 2014)

difalkner said:


> You are going to post photos, right?
> 
> David


Yep. On their new riser design the 4 bolts that hold the gantry beam have washers under them. I'm thinking the holes beneath the bolt heads may be slightly oversized, in which case loosening them all may permit squaring up the assembly before tightening them all down. 

4D


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## beltramidave (Jan 6, 2016)

honesttjohn said:


> Right now Probotix has a 4 day sale starting --- 20% off.


Heck of a sale for anyone wanting a Probotix machine! I just sent a quote in for a Meteor for work as they were looking for a "spare" machine. That would make 7 Probotix machines I have set up for a specific operation.


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## 4DThinker (Feb 16, 2014)

Yesterday I rechecked the Z axis and now that the machine parts have warmed up the out of squareness has reduced down to almost nothing. Still a small fraction of a degree off, but less than what I found our old meteor was off. Once the router we bought for it comes in I'll check again. 

The 10% and now 20% off sales that Probotix has been running makes me curious. Perhaps they made a big investment in extrusion and other parts to get a price break and now are encouraging sales to reduce the space all that stuff takes up. Not complaining mind you. Just curious.


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## difalkner (Jan 3, 2012)

beltramidave said:


> Heck of a sale for anyone wanting a Probotix machine! I just sent a quote in for a Meteor for work as they were looking for a "spare" machine. That would make 7 Probotix machines I have set up for a specific operation.


We'd love to see a photo of all those machines, assuming it's permissible to do so.

David


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## honesttjohn (Feb 17, 2015)

4D

I heard they're moving to Atlanta and are trying to get rid of as much stuff as possible so they have less to move. No facts - just what a little birdee said.


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## 4DThinker (Feb 16, 2014)

I've got a sister who lives in Atlanta, and every even numbered year there is a woodworking trade show that sponsors a furniture design competition for college students that I attend occasionally. I may have to visit their factory next time I'm down there. 

4D


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## HDVideo (Mar 8, 2018)

4DThinker said:


> The only way I can see to square the Z axis assembly is to rotate the gantry beam. Two bolts on each side hold the beam to the vertical side plates. These bolts go through holes in the side plates with no obvious slop in the fit. The solution I see is to remove the two front bolts, ream out the holes they went through, crank the whole beam/Z axis forward until plumb then insert and tighten those two bolts.
> 4D


If I understand your issue, would it be possible to shim the router mount rather than try to rotate the gantry beam? If your machine is like mine, they use four Delrin or similar spacers between the router mount and Z-Plate. Maybe an adjustment to those spacers would solve your problem.

Ed


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## 4DThinker (Feb 16, 2014)

HDVideo said:


> If I understand your issue, would it be possible to shim the router mount rather than try to rotate the gantry beam? Ed


The router mount is flush/square to back plate, the plate is parallel to the guide rails. The guide rails run through bearings that are mounted on a bracket that surrounds the gantry beam. Shimming just the router mount would still have the router coming down a fraction of a degree off vertical. Only rotating the gantry beam would allow straightening the guide rails to vertical relative to the bed frame. 

The CNC is a Probotix GX25x25 (formally called a Comet) https://www.probotix.com/CNC-ROUTERS/CNC-ROUTER-GX2525-COMET, and although they haven't updated the photos to reflect the latest changes to their designs, the Z axis is essentially the same design. 

4D


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## HDVideo (Mar 8, 2018)

4DThinker said:


> The router mount is flush/square to back plate, the plate is parallel to the guide rails. The guide rails run through bearings that are mounted on a bracket that surrounds the gantry beam. Shimming just the router mount would still have the router coming down a fraction of a degree off vertical.
> 
> 4D


I have the Asteroid model and see what you are talking about. Would it be possible to shim either the top or bottom of the bearing to make the Z guide rails perpendicular to the bed? On mine, I've go so much slop in those bearings that being off a little is the least of my worries. lol

BTW, I've created a complete CAD drawing of the Asteroid in Fusion 360. I'd be happy to share it with any members here that are interested.

Ed


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## honesttjohn (Feb 17, 2015)

Bearings can be replaced -- according to Probotix. They recommend every year, but my Nebula is over 3 years old and still seems to be tight.


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## beltramidave (Jan 6, 2016)

Ed,
I will take the cad drawing if you want to share it 
Dave


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## HDVideo (Mar 8, 2018)

I have replaced them and didn't seem to help. I used bearings off eBay, so maybe if I'd used better bearings it would have helped, but how do you know that what you're getting is any good.


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## HDVideo (Mar 8, 2018)

beltramidave said:


> Ed,
> I will take the cad drawing if you want to share it
> Dave


If you use F360, I can share it with you there or I could upload it to Dropbox and send you the link. If you don't use F360, what format would you like?

Ed


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## 4DThinker (Feb 16, 2014)

The new design uses two bearings for each rail, set apart to help stiffen the Z axis when fully extended. The bearings are open face and appear to be adjustable to tighten up if needed. Kind of like these: https://www.aliexpress.com/item/1PC...ar-Guide-Mechanical-Hardware/32855491181.html

I've stared at the assembly on multiple occasions and am pretty sure the only way to adjust is to twist the whole beam back. On this new Comet the off-vertical could be the result of very minor clearance in gantry bolt holes that let the assembly rock forward with the weight of the cantilevered Z assembly. If they don't have the Z assembly vertically braced when they tighten the beam to the side risers then this would be more likely to happen than not. 

On the older Meteor we have the gantry is tipped back rather than forward. That may be from coming down on clamp bolts while in use that result in twisting the beam/assembly back. It also may be accumulated error built up over several years of use. 

4D


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## HDVideo (Mar 8, 2018)

I've looked at their new design and agree, it should be much better than what we currently have on our machines. I recently designed and uploaded a Z-Axis assembly to GrabCad that could be used on any router, but could easily be retrofitted to the older Probotix machines. Unfortunately, it wouldn't address your misalignment issue or the inherent lack of stiffness in in the design. I created two assembly designs, one using 15mm guide rails and the other with 20mm rails. The link below is for the 15mm version and would be more than adequate for any Probotix machine, I would think.

https://grabcad.com/library/z-axis-assembly-15mm-guide-rails-1


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## 4DThinker (Feb 16, 2014)

Awhile back I designed an alternative version of their Z axis assembly that would have less mass for the stepper to lift and more clearance for the spindle as it comes down. I sent the design to Probotix and their reply was that their existing configuration was specifically used because it was easier to reliably/repeatedly machine the parts needed. Less jigging up leading to fewer chances for machining errors. 

4D


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## honesttjohn (Feb 17, 2015)

I think that means -- cheaper and faster to make.


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## beltramidave (Jan 6, 2016)

Thanks Ed. I have used F360, so that or any CAD format will work.
You can PM me a link or a file, either way.


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## HDVideo (Mar 8, 2018)

beltramidave said:


> Thanks Ed. I have used F360, so that or any CAD format will work.
> You can PM me a link or a file, either way.


Did you receive the email with an invitation to join the shared Probotix Asteriod folder on F360? If you can't download it that way, I'll try putting it in DropBox. The file was too large to email.

Ed


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## beltramidave (Jan 6, 2016)

HDVideo said:


> Did you receive the email with an invitation to join the shared Probotix Asteriod folder on F360? If you can't download it that way, I'll try putting it in DropBox. The file was too large to email.
> 
> Ed


Did not receive an email or PM. I sent you a PM.


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## HDVideo (Mar 8, 2018)

beltramidave said:


> Did not receive an email or PM. I sent you a PM.


My apologies, Dave. I sent it to "the other Dave". Your invitation is on the way. 

Ed


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## beltramidave (Jan 6, 2016)

HDVideo said:


> My apologies, Dave. I sent it to "the other Dave". Your invitation is on the way.
> 
> Ed


Got it. Thanks Ed.


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## 4DThinker (Feb 16, 2014)

More bad news about the GX2525 (Comet) we just bought. I made up toolpaths to cut t-slots into the MDF bed so we could put it to use today. I started up the file, but as the cut was kicking up considerable dust (no functioning dust collector available) I left it running while I talked to my morning class students. 

When I heard it stop I went into the CNC room only to see the right Y stepper had been losing steps throughout the cut. The gantry was now racked, with the right side about 1.5" farther from the front than the left. I turned off the controller and manually twisted the stepper to bring it back inline and realized the coupler was loose on that acme screw. The toolpath it had cut was to be just the initial pocket with an endmill before then running a t-slot bit. It should have been perfectly parallel rows of slots, but the results were progressively off alignment as the right stepper had fallen behind. I didn't have anything with me to take a photo of, but I'll post one tomorrow. I've tightened the coupler, but am a bit hesitant to trust this machine for cutting students projects. Friday last week I found that the two bottom center holes on the router mount face hadn't been tapped. 

4D


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## HDVideo (Mar 8, 2018)

Sorry to hear that 4D. Sounds like QC is slipping a bit at Probotix.


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## 4DThinker (Feb 16, 2014)

Yep HD. My thoughts exactly. Crate arrived with a stray bolt loose. Ended up coming from the left front frame bracket that holds the left Y stepper and the front frame rail to the side. Backer plate for the router/spindle clamp had two bottom center holes that hadn't been tapped out. Z axis is off vertical by a bit (less that one degree but noticeable), and now the right Y stepper coupler was loose. Starting to expect to find something else loose/off tomorrow. 

Fortunately this Comet lives in a Fabrication Lab that could probably make a CNC from scratch and easily remedy each of the found flaws. 4th one I've had though and the first three have been nearly flawless and running fine for several years now. 

4D


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## beltramidave (Jan 6, 2016)

That is disappointing for sure. I haven't gotten a ship date yet for the new Meteor (or whatever it is called now). I will let you know how it goes when I get it.


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## 4DThinker (Feb 16, 2014)

Attached are photos of the MDF board after the CNC was done with it. The slots should have been two parallel columns, perfectly aligned with each other. All the slots show stair stepping, more so on the right end of each. 

For what it is worth, their new name for a Meteor is GX2550. 
The Comet is a GX2525, but only has 24.125" of travel in the Y direction, but 26" in the X direction, suggesting it should have been a GX2624. 

4D


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## difalkner (Jan 3, 2012)

That's a bummer, for sure! Looking at the end result I would hate to have to replicate that if asked - that would not be easy.

I assume it's corrected and now you'll get on with cutting it properly. 

David


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## 4DThinker (Feb 16, 2014)

difalkner said:


> I assume it's corrected and now you'll get on with cutting it properly.
> 
> David


I tightened up the right coupler as best I could. It didn't seem loose at first, but I got a 1/4 turn out of it which I hope is enough to make sure it won't slip. I'm hoping a loose coupler was actually what caused the missed steps because if it wasn't then there is something more insidious going wrong. 

I'm tossing out the MDF sheet as today we cut out parts (using a large Multicam CNC) for my adjustable angle clamping jig which should be a much more versatile "bed" for this comet. The jig can be horizontal or vertical or any angle in between, and will fill up the entire cutting area when locked horizontally. 

4D


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## difalkner (Jan 3, 2012)

It would be nice to see photos of that jig when you get it finished. 

Does the coupler shaft have a flat spot or key?

David


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## 4DThinker (Feb 16, 2014)

difalkner said:


> Does the coupler shaft have a flat spot or key?
> 
> David


Without taking it apart I can't be sure. The coupler connects the stepper shaft with the end of the acme threaded feed screw. The opposite end of the stepper doesn't have a flat spot, so I doubt the coupler end does. The Acme rod might, but given how far off the MDF job left it I seriously doubt it. 

I'm already using a small version of that jig on my home Meteor, and a large one for the Meteor at work. It only uses the front rail to connect to and fills up less than half the Meteor bed, but the new one will fill up the whole bed area of the new Comet. 

4D


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## difalkner (Jan 3, 2012)

Ah, yes, I recall going to your page and seeing that. Looks very versatile. Frank Howarth just built one for his huge CNC router and it looks pretty cool, too. I don't have room for one, unfortunately.

David


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## 4DThinker (Feb 16, 2014)

Well, it turns out that there must be a flaw with the controller that controls the right Y stepper. I know all the couplers are tight, after homing correctly I sent the router to the center back, then to the front. The right stepper does an odd counterclockwise spin before reversing to then move forward. The same happens when jogging in the -Y (toward the front) and sending g-code to do the same. The right side gets a negative spin before trying (too late) to catch up to the left side. 

Probotix is sending a new Unity Controller. 

4D


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## MEBCWD (Jan 14, 2012)

4DThinker said:


> Probotix is sending a new Unity Controller.
> 
> 4D


Will they be sending a new sheet of MDF in the package with the controller?:grin:


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## 4DThinker (Feb 16, 2014)

MEBCWD said:


> Will they be sending a new sheet of MDF in the package with the controller?:grin:


No, but then again I don't need one. I was only trying to use the original one as a temporary way to hold down work before my clamping fixture is ready to install. The parts for that fixture were cut out yesterday. Today I installed threaded inserts and glued the braces to the main plate. I have to make a hardwood top bar to connect the two braces and permit bolting into the CNC frame. I may have to add some cross pieces to the base I made to hold the bottom of the fixture steady. 

4D


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## beltramidave (Jan 6, 2016)

4DThinker said:


> Well, it turns out that there must be a flaw with the controller that controls the right Y stepper. I know all the couplers are tight, after homing correctly I sent the router to the center back, then to the front. The right stepper does an odd counterclockwise spin before reversing to then move forward. The same happens when jogging in the -Y (toward the front) and sending g-code to do the same. The right side gets a negative spin before trying (too late) to catch up to the left side.
> 
> Probotix is sending a new Unity Controller.
> 
> 4D


Did they try and troubleshoot the problem with you? Not sure that it seems logical that it could be something as simple as a DIP switch setting on the driver being wrong since it homes ok.

I thought with the new software configurator, that you could swap drivers in the setup, just for this kind of problem.

Just curious...


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## 4DThinker (Feb 16, 2014)

beltramidave said:


> Did they try and troubleshoot the problem with you? Not sure that it seems logical that it could be something as simple as a DIP switch setting on the driver being wrong since it homes ok. ... Just curious...


Melissa from Probotix sent me an email late yesterday asking if I could call them when standing in front of the machine so they could have me do some tests. This was after we got an email stating they were sending a new Unity and another with a shipping/tracking number for that controller. 

Assuming the A axis jack is internally connected to a controller card then I suppose that jack could be swapped for the Y2 stepper to see if it was just one bad controller card. Not that that would appease me as we did pay already for a working machine with no bad unity internals and have already ruined the MDF spoilboard thanks to the defect. BTW they did claim a significant delay in shipping was in part due to them needing to thoroughly test the machine. Surely any good test would have noticed this flaw. 

Homing works because even after a slow start that right Y stepper eventually does hit its limit switch before the routine finishes up and leaves the spindle in place (front left corner) with no new movement. Any jog in the +y direction looks to be fine, but jogging in the -Y direction has that right Y stepper doing its odd dance before actually getting to work. Same with any g-code commands that move the spindle in the -Y direction (toward the front). 

4D


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## 4DThinker (Feb 16, 2014)

Little luck talking with Probotix today. The room where we have the 3 CNCs from them is in a basement fabrication lab, essentially a cement and rebar faraday cage where cells signals and even wifi has trouble making it through. I did get one choppy connection with someone at Probotix over wifi but with machines running in the background and the dust collector system whistling in the CNC room itself I couldn't make enough sense to what was being said to make it worth trying to stay connected.

I did get the jig mounted on the frame though. The new Unity controller should be here Monday. Hopefully it will turn this sad Comet into the shiny new contributor to woodworking magic it was intended to be. 

The action of the right Y stepper is still the most odd thing I've ever seen a CNC do. It looks like it would take some devious coder to hack the g-code interpreter between LinuxCNC and the controller card. In theory both Y steppers should get identical cloned commands, but the right twin seems dyslexic. It'll start out spinning the wrong direction, and only appears to correct itself once it sees across the bed what the left stepper is doing. It reminds me of high school marching band where there was always at least one kid that would head the wrong direction during transitions between songs while doing the football halftime show. 

4D


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## BalloonEngineer (Mar 27, 2009)

have you tried switching cables? That type of action could be when the "direction" pin signal is not making a reliable connection.


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## 4DThinker (Feb 16, 2014)

BalloonEngineer said:


> have you tried switching cables? That type of action could be when the "direction" pin signal is not making a reliable connection.


I can't (easily) switch out the cable coming from the Y2 stepper to the controller. Hardwired to the stepper and fed through a cable chain along with several other cables it would be a mess to tackle. There is a parallel cable between the PC and the controller that handles all the signals and "might" be where a short lies. Only one pin would have to be bad, but the flaw only happening during -Y moves, and being reliably consistent, doesn't seem like an intermittent short to me. The new controller is also coming with new parallel and USB cables just in case. I'll try just the new parallel cable first, to see if that was where the flaw was. If the Y2 stepper suddenly behaves properly with the old controller then a bad parallel cable will have proven once again to be where the fault belonged. I know more than a few probotix CNC owners who started out with non-working machines caused by a bad parallel cable. 

4D


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## beltramidave (Jan 6, 2016)

4DThinker said:


> I can't (easily) switch out the cable coming from the Y2 stepper to the controller. Hardwired to the stepper and fed through a cable chain along with several other cables it would be a mess to tackle. There is a parallel cable between the PC and the controller that handles all the signals and "might" be where a short lies. Only one pin would have to be bad, but the flaw only happening during -Y moves, and being reliably consistent, doesn't seem like an intermittent short to me. The new controller is also coming with new parallel and USB cables just in case. I'll try just the new parallel cable first, to see if that was where the flaw was. If the Y2 stepper suddenly behaves properly with the old controller then a bad parallel cable will have proven once again to be where the fault belonged. I know more than a few probotix CNC owners who started out with non-working machines caused by a bad parallel cable.
> 
> 4D


Could easily swap Y cables at the back of the controller and see if the problem follows the cable. If it doesn't then either driver or computer/signal issue. Since you have other machines, could swap parallel cable just for testing.

Still pretty sure that with their "configurator" software setup, you can swap drive signals to the "spare" drive, but probably not worth the effort with a new controller coming. 

Good luck.


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## 4DThinker (Feb 16, 2014)

At the moment, any time I'm in the small CNC room where the new Comet is I've got students using the other two Probotix CNCs. Yes all sorts of swaps could be done given the flock of "parts" I have, but those parts are busy. The shop is also a busy, noisy, distracting environment where the concentration needed to contemplate debugging logistics is hard to find. 

I'm content to try the new parallel cable first. If the Comet behaves the same with new cable I'll swap out the current Unity for the new one. 
Even if I could have gotten the comet working with port swaps I'd still have has a defective controller where I should have a brand new fully operational one. I could accept that with either of my older machines that are way past any warranty. This little comet is brand new, and should be running perfectly, 100% to start out. 

4D


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## 4DThinker (Feb 16, 2014)

The new controller arrived today. Before swapping out the controllers I swapped in the new parallel cable just to see if that might have been the problem. Sure enough the GX2525 (Comet) ran fine now and even succeeded in cutting a test file with no flaws.

Rather than ship back the controller they sent I offered to buy it from them as a backup for my personal meteor. They agreed and threw in a 20% discount. Photo attached is the new CNC on the base I made for it and my jig attached to the front frame rail.

4D


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## beltramidave (Jan 6, 2016)

Looks like they may want to find a different vendor for their parallel cables..
Glad you got it going!


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## 4DThinker (Feb 16, 2014)

For those interested the base is an update of one I made for the Nebula we have in the same shop. This one has longer legs as we often do joinery cuts on the end of long stretchers clamped vertically. The strusswork cutouts on the base stretchers are there to permit reaching through them to add or tighten clamps to the jig, sweep under the table or more easily retrieve bits or router wrench that may have dropped to the floor. 

Using this smaller (than a Meteor or Nebula) Comet it makes more sense to use the "send to rear" and "move to front" commands available in the provided LinuxCNC install. I send it to the rear center after a cut to get it quickly out of the way, and I'll send it to the front center or system Home right before zeroing out work I may have clamped to the jig. Such moves don't make as much sense on beds that are longer like our Meteor and Nebula.

4D


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## HDVideo (Mar 8, 2018)

Good to hear you got it working!


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