MACH3 Shaking and jittery on 3D relief cut

chemstock
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Re: MACH3 Shaking and jittery on 3D relief cut

Post by chemstock »

Can't speak to the Legacy Maverick, The website claims it uses a 3HP water cooled spindle. Though good, vibration can be caused by loading. If you have vibration reaching into the frame, you have a problem. Put your hand on the gantry, if you can feel vibration at an corner or en end cut, you have to deal with the issue.
While the manufactures make claims, it comes down to the material you are using, feed rate and the bit selection. A 3HP CNC from one manufacturer will not significantly outperform the same spindle on another manufacturer. I use a Richauto, which has its limits but I would be surprised to see a different controller have significantly better performance. I created some GCode with a Mach 3 post processor and found it essentially the same as the Gcode from by Richauto.
For 3D modeling, you want to keep precision to 0.1mm or the limits of the machine. Simply can't meet that standard if there is vibration.
On the machine, reduce the acceleration variables.
On the tools, use three fluted spiral bits (NO to standard router bits). Two flutes can contribute to vibration. Use only sharp sharp sharp tools.
On the model, reduce the feedrate, use ramps and reduce stepover to lower the chip load.
On materials, have to reduce feed rate for hard woods like white oak or maple.

While cutting, you should not hear or feel any vibration, the spindle should not reduce speed on heavy cuts.

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Leo
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Re: MACH3 Shaking and jittery on 3D relief cut

Post by Leo »

Shaky jittery stuff has to do with CV, and exact stop and a few other things. Greolt is highly knowledgeable in Mach 3. I would defer to his knowledge on the subject. I have played around a bit in Mach3 settings and the combination add up to a LOT of variations.

Play around with what he suggested. Go back and forth with him for a while. He know that stuff really well.
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neverhappen
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Re: MACH3 Shaking and jittery on 3D relief cut

Post by neverhappen »

Brian,

if you get this, finally came to a conclusion that pretty much solved the problem.
"Dirt"
I had enough build up from the rails and pinions wearing from initial brake in to cause the inability to take the slack/chatter out of the X axis. Being as the pinion needs to have almost "0" tolerance while it engages the rail, when trying to adjust the dirt and debris wouldn't allow me to get it tight enough. That caused the slack which in turn cause the chatter.
I sprayed cleaner on the rails, did the best I could with the pinion gears, wiped it down and applied the recommended "Dyna Glide"
The tolerance is tight now, no more chatter at high speeds, and a much cleaner cut.
Hope this helps

bbiehl
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Re: MACH3 Shaking and jittery on 3D relief cut

Post by bbiehl »

Neverhappen,
Interesting, My chatter wasn't as bad as yours apparently and it was only while doing 3d type cuts. As long as I keep the speed below 80ipm it was okay. I will check my rails to see if that is my problem also. Thank you for the info.
-brian

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