Trying to troubleshoot some jerky motion in cuts

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ShawnM
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Re: Trying to troubleshoot some jerky motion in cuts

Post by ShawnM »

I also agree with Gary's comments. I love belt reduction machines and always use 25mm belts and pulleys. Most of my retrofits are European machines so the belts and pulleys are metric with T10 pitch but always 25mm wide. I recently even switched to Gates poly belts with a steel core, although slightly more noisy, they have several advantages over rubber belts. The main two that stand out are they are far stronger and dont stretch over time. They also last a very long time.

Back to your mechanical reduction, another option you have is new pulleys. On a few routers I've retrofit to cut aluminum I've even gone as far as replacing the pulleys to get better mechanical reduction as it's the easiest and least expensive way to get in that "sweet spot". It does not appear you can go any larger on the driven pulley (maybe a few teeth?) but you could get a smaller drive pulley to help. Not sure of the bore size on your pulley but even going as low as a 14 or 15 tooth pulley would get you in the 4:1 or higher gear reduction range. This would help when using a router as a mill. :D

I do use Clearpath servos on my retrofits and use a higher steps/rev as well when building machines to cut aluminum or acrylic.

Lastly, have a closer look at the rack and pinion, depending on the age of the machine you might want to, at the very least, make some adjustments. Helical rack and pinion are far better than straight gears but I'm guessing this machine has straight gears.
ssaxer
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Re: Trying to troubleshoot some jerky motion in cuts

Post by ssaxer »

My machine ( a K2 2436 cnc with an acorn controller) seems to come to a brief pause at the end of each line. Is there a lookahead parameter I should be adjusting
cnckeith
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Re: Trying to troubleshoot some jerky motion in cuts

Post by cnckeith »

ssaxer wrote: Tue Apr 02, 2024 7:17 pm My machine ( a K2 2436 cnc with an acorn controller) seems to come to a brief pause at the end of each line. Is there a lookahead parameter I should be adjusting
post a fresh report.zip so we can 'see' your configuration and a copy of the offending g code.

are you using g code smoothing?
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ssaxer
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Re: Trying to troubleshoot some jerky motion in cuts

Post by ssaxer »

I have attached a copy of the "report.zip" and the code I am running. What the machine does is move either X or Y and seems to stop at the end of each line. I am not sure how to turn on smoothing.
Attachments
locating pocket .nc
(9.15 KiB) Not downloaded yet
report_1442FC0C6D65-0919226527_2024-04-04_19-33-06.zip
(948.41 KiB) Downloaded 2 times
ssaxer
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Re: Trying to troubleshoot some jerky motion in cuts

Post by ssaxer »

Who knew that there was a smoothing button. I have turned it on and tried another program but still get the same thing. I have added a link to a video file that shows the motion.


cnckeith
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Re: Trying to troubleshoot some jerky motion in cuts

Post by cnckeith »

just looks like you have your accel times high/long and still at the stock settings of .5 seconds.
try .2 seconds for X , Y and Z axis.
Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
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cnckeith
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Re: Trying to troubleshoot some jerky motion in cuts

Post by cnckeith »

and please start you own thread and follow the posting guidelines.
https://centroidcncforum.com/viewtopic.php?f=60&t=1043
and put all the photos in one spot, its really nice to have all the photos of your project in a photo album that you can just keep adding photos to and it always has the same album link all at high resolution so we can zoom in and see what we need to see to help you. . here is how.
Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
Gear we use but don't sell. https://www.centroidcnc.com/centroid_di ... _gear.html
cnckeith
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Re: Trying to troubleshoot some jerky motion in cuts

Post by cnckeith »

ssaxer wrote: Thu Apr 04, 2024 10:58 pm Who knew that there was a smoothing button. I have turned it on and tried another program but still get the same thing. I have added a link to a video file that shows the motion.


and please start you own thread and follow the posting guidelines.
https://centroidcncforum.com/viewtopic.php?f=60&t=1043
and put all the photos in one spot, its really nice to have all the photos of your project in a photo album that you can just keep adding photos to and it always has the same album link all at high resolution so we can zoom in and see what we need to see to help you. . here is how.
Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
Gear we use but don't sell. https://www.centroidcnc.com/centroid_di ... _gear.html
cnckeith
Posts: 7314
Joined: Wed Mar 03, 2010 4:23 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: Yes
Oak CNC controller: Yes
CNC Control System Serial Number: none
DC3IOB: Yes
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CPU10 or CPU7: Yes
Contact:

Re: Trying to troubleshoot some jerky motion in cuts

Post by cnckeith »

ssaxer wrote: Thu Apr 04, 2024 10:43 pm I have attached a copy of the "report.zip" and the code I am running. What the machine does is move either X or Y and seems to stop at the end of each line. I am not sure how to turn on smoothing.
and please start you own thread and follow the posting guidelines.
https://centroidcncforum.com/viewtopic.php?f=60&t=1043
and put all the photos in one spot, its really nice to have all the photos of your project in a photo album that you can just keep adding photos to and it always has the same album link all at high resolution so we can zoom in and see what we need to see to help you. . here is how.
Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
Gear we use but don't sell. https://www.centroidcnc.com/centroid_di ... _gear.html
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