Mach3 movement on CNC is driving me mad!

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After another weekend trying to fix this weird issue, a friend had the idea that I should try running an old gcode created before any changes, such as new motors or breakout board. I did this & my machine suddenly performed as normal. I ran 2 small clock parts. I pulled up that DXF & ran it through aspire again & the new gcode again, created undersized parts with the cog teeth not in proportion. The problem was not my new motors, break out board, backlash or any mechanical issue, it was aspire!!! I have aspire on another computer that runs a CNC milling machine so I created the same gcode on that & transferred it to to my router computer on a USB & it ran fine. Also put that DXF through artcam on the router computer & that worked too. How can aspire corrupt itself in this way. I uninstalled & re installed aspire & while it dumped my tool list, it seemed to have kept some settings & was still not working properly. Time to look for some free CAM software!!! Hopefully this might help someone as it's not always the usual suspects, backlash, play in guide rail or some other mechanical issue. Thanks for all the replies
 
That's interesting; it makes you wonder what they aspire to.
I've got an inexplicable error on my Denford. I've been through the process of eliminating backlash (it's an old machine) but there is still a small but repeatable error. The error in the Y direction is smaller than the X. I've been using CamBam and am halfway through my trial allocation, so I'd be very interested if you find a reasonably priced CAM package. Qcadcam is another one but the CAM aspect of it is not usable on a trial basis. That's a pity because the CAD side is a respectable 2D drawing app which is free.
Brian
 
That's interesting; it makes you wonder what they aspire to.
I've got an inexplicable error on my Denford. I've been through the process of eliminating backlash (it's an old machine) but there is still a small but repeatable error. The error in the Y direction is smaller than the X. I've been using CamBam and am halfway through my trial allocation, so I'd be very interested if you find a reasonably priced CAM package. Qcadcam is another one but the CAM aspect of it is not usable on a trial basis. That's a pity because the CAD side is a respectable 2D drawing app which is free.
Brian
I'm looking for free software as the price of any won't be as cheap as just binning that computer & buying another old XP comp. I don't think I'd ever be able to get rid of aspire completely without it keeping whatever went wrong with it to begin with. Really strange, it worked on that computer for at least 4 years I think!
At least I know what's wrong with it now!!! With your Denford, can't you compensate for the backlash in mach3 or whatever you use?
 
I'm looking for free software as the price of any won't be as cheap as just binning that computer & buying another old XP comp. I don't think I'd ever be able to get rid of aspire completely without it keeping whatever went wrong with it to begin with. Really strange, it worked on that computer for at least 4 years I think!
At least I know what's wrong with it now!!! With your Denford, can't you compensate for the backlash in mach3 or whatever you use?
I do incorporate compensation by adding 0.2mm to the tool diameter. As there is a difference between the X and Y errors I end up with a small +ve error on the X axis and a -ve on the Y. In practice I don't think it's going to be a problem for me (I'm also making clock gears). It's just annoying that the problem is there and I have to keep it in mind when writing the g-codes. I haven't got going on my next clock project yet, just been playing around with test cuts. The machine is driven by Denfords own software - quite old now but generally considered reliable.
Brian
 
I do incorporate compensation by adding 0.2mm to the tool diameter. As there is a difference between the X and Y errors I end up with a small +ve error on the X axis and a -ve on the Y. In practice I don't think it's going to be a problem for me (I'm also making clock gears). It's just annoying that the problem is there and I have to keep it in mind when writing the g-codes. I haven't got going on my next clock project yet, just been playing around with test cuts. The machine is driven by Denfords own software - quite old now but generally considered reliable.
Brian
Was trying to add a video but wont let me
 
I have aspire on another computer that runs a CNC milling machine so I created the same gcode on that & transferred it to to my router computer on a USB & it ran fine.
Do you have gcode of the same part, produced by Aspire on the "wrong" computer as well as the "right" computer? It might be possible to spot differences in setup from that code.
 
Do you have gcode of the same part, produced by Aspire on the "wrong" computer as well as the "right" computer? It might be possible to spot differences in setup from that code.
This continuing saga had me at my workshop this morning before work, full of bravado that I was going to uninstall aspire, but this time go deep in the registry. I used find & find next to delete anything even remotely connected to vectric/aspire. Aspire this time did start from scratch but the resultant cog was the same!!! Still undersize & not proportioned correctly. The gcodes I've added are artcamcog using artcam that is on the CNC router computer where corrupted aspire lives. Goodcog was created with aspire on a different computer & nogoodcog is obviously the undersized gcode. The cogs that I ran with the artcam & aspire from the different computer are exactly the same size as I expected. 0.3 oversized but the teeth are proportionate to the original vector
 

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There's certainly some major differences between the good and bad Aspire outputs; for a start the files are a different size. There's also a different feed speed configured; e.g. the good version's first cutting move is:

G1Z0.000F1200.0

And the bad version is some 50% faster (I assume these figures are mm/min):

G1Z0.000F1800.0

Are you sure that both installs of Aspire are:

1. Producing gcode from the same drawing/model?
2. Using the same post processor (i.e. for Mach 3)?
3. Have the same machine settings?
4. Have the same tool database settings?
 
The differing feed speeds are because the good code is from aspire that I use for a milling machine. Yes, they are both created from the same drawing as I have them on both computers. The parts I was trying to run are all parts that I have made before. As I said, I tried some gcode that I created before aspire had a fit & they are fine. I'm totally lost with this one. I set up the 1.5mm end mill on the good aspire in the same way as on the bad, I just forgot to change feed speeds, but I have mucked about with feeds & speeds during this process & still no good
 
If you have the will for it (and I accept it's tedious) try exactly the same drawing on both computers, and try to match all the milling settings you can find (including feed speeds), then generate gcode again and I'd be happy to take another look.

I'm assuming both computers are running the same version of Aspire? The fact the two files are quite different means there must be something not the same between the two installs.
 
If you want to send me or put it on drop box the Aspire crv file were you designed the wheel out I can go through all your settings prior to and including creating the g-code and have a good look whats going off in there.
 
If you have the will for it (and I accept it's tedious) try exactly the same drawing on both computers, and try to match all the milling settings you can find (including feed speeds), then generate gcode again and I'd be happy to take another look.

I'm assuming both computers are running the same version of Aspire? The fact the two files are quite different means there must be something not the same between the two installs.
I can do that but will have to be at the weekend. I remember now when this aspire actually went wrong. I needed to re run some clock parts, 2 larger cogs came out OK but everything subsequent to them went wrong. Any new gcode was weird. I will also centre both parts to the same size work area & run the part & take pictures of both so you can see the results.
 
Finally got down my workshop to create the gcodes. Also attached a pic of what I end up with. Note that the Artcam software is on the same computer as the bad Aspire
 

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Based on the fact the good and bad Aspire gcodes look to be doing broadly the same thing: same start and finish codes (including the same tool number), same feed speeds and Z heights, but the X and Y values differ between the two; my guesses are:

1. There might be differences in the tool configuration (one install has tool 1 as a different diameter to the other)
2. The bad Aspire might have some sort of compensation enabled; e.g. under or overcutting (sometimes used to undercut before doing a finishing pass)

If Aspire stores its config in a file you could check the difference between the two installations. Alternatively it might require taking some screen shots whilst going through the CAM configuration screens and comparing the two.

EDIT: If you could make a simple, say 50x50mm square, then set that up to be cut externally (i.e. you end up with a square of 50x50mm, whatever depth), and generate the gcode for that on both systems (good and bad Aspire) that might be useful. Also - what's the cutter diameter set to?
 
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Based on the fact the good and bad Aspire gcodes look to be doing broadly the same thing: same start and finish codes (including the same tool number), same feed speeds and Z heights, but the X and Y values differ between the two; my guesses are:

1. There might be differences in the tool configuration (one install has tool 1 as a different diameter to the other)
2. The bad Aspire might have some sort of compensation enabled; e.g. under or overcutting (sometimes used to undercut before doing a finishing pass)

If Aspire stores its config in a file you could check the difference between the two installations. Alternatively it might require taking some screen shots whilst going through the CAM configuration screens and comparing the two.

EDIT: If you could make a simple, say 50x50mm square, then set that up to be cut externally (i.e. you end up with a square of 50x50mm, whatever depth), and generate the gcode for that on both systems (good and bad Aspire) that might be useful. Also - what's the cutter diameter set to?
I will check tomorrow but not sure I will find any differences that would cause the issue between the 2 aspires. It is entirely possible that I accidentally changed a setting on my original install & that's when it went wrong but I have since uninstalled & re installed aspire, including deleting everything in the registry. I'm going to go through your suggestions as you never know!!! I will check screens & any settings folders in programme files. I've done 25mm circles & they are as wrong as the cogs by the same amount but the squares seem a better idea because i assume the gcode is easier to follow. Thanks
 
I will check tomorrow but not sure I will find any differences that would cause the issue between the 2 aspires. It is entirely possible that I accidentally changed a setting on my original install & that's when it went wrong but I have since uninstalled & re installed aspire, including deleting everything in the registry. I'm going to go through your suggestions as you never know!!! I will check screens & any settings folders in programme files. I've done 25mm circles & they are as wrong as the cogs by the same amount but the squares seem a better idea because i assume the gcode is easier to follow. Thanks
My only other thought is: you can set your CAM stage to do a cut inside, outside, or on the line. If the "bad" parts are small by 1/2 the cutter diameter that would be an explanation for the difference (cutting on, rather than outside). But it would still be a great idea to try a square.
 
My only other thought is: you can set your CAM stage to do a cut inside, outside, or on the line. If the "bad" parts are small by 1/2 the cutter diameter that would be an explanation for the difference (cutting on, rather than outside). But it would still be a great idea to try a square.
I'm more intrigued by the finishing cut you mention, maybe something like that is ticked. Everything I've been trying to run has been an outside cut. Lots to check tomorrow!
 
I'm more intrigued by the finishing cut you mention, maybe something like that is ticked. Everything I've been trying to run has been an outside cut. Lots to check tomorrow!
It would be slightly odd, as the finishing pass is intended such that your cuts leave parts fractionally oversized, then it's followed by a single full depth "thin" cut to bring a part accurately into size. Obviously you're seeing the opposite here: parts being overcut.

Do you have a measurement of how much the parts are undersized, vs the diameter of the cutter you're using?
 
It would be slightly odd, as the finishing pass is intended such that your cuts leave parts fractionally oversized, then it's followed by a single full depth "thin" cut to bring a part accurately into size. Obviously you're seeing the opposite here: parts being overcut.

Do you have a measurement of how much the parts are undersized, vs the diameter of the cutter you're using?
I can't win. I just got here & the 36v power supply that runs my Z is dead!!! Anyway, cutter diameter is 1.5mm & actually is that size. The cog I've been messing about is 27.987mm at it's largest & the teeth have a max width of 3.2. When run with bad aspire, I get 27.3 on the y & 27.5 on the x. The problem is the teeth. As I said previously, even if I change my steps per mm or enlarge the vector, the teeth are still small & out of proportion. When this aspire worked or with the other aspire now, they would be 0.3 over, I would reduce size of the vector & the teeth would stay in proportion. Even if I can't run anything today, I will still create the gcode for a square & see what I can see. I've checked differences in settings between the 2 aspires & I can't see any.
 
" Finally got down my workshop to create the gcodes. Also attached a pic of what I end up with. Note that the Artcam software is on the same computer as the bad Aspire "

One other thing to check if you have Artcam and Aspire running on the same computer Aspire might be picking up some stray settings just a thought.
 

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