Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: Chuck D on June 04, 2019, 06:48:40 AM
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I'm still looking for help with the CV setting.
I was told by one individual that my setting should be ".5" , and currently I am set at 180.
That's a big difference, and nobody seems to be in the know about it.
I have an import machine with USB motion control.
Any help is greatly appreciated.
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:)
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Thanks. I'll read and try to understand that later today. I have read it once, and it was over my head. I've picked up some knowledge since then(maybe)
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I set Stop CV on Angles to 89°, and turn off all other CV settings, both in General Config, and on the Settings page.
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Thanks Gerry. I set the Stop/angle to 89° and every other box is unchecked/not green, on both screens. I'll run a carve and see how it goes.
I read and reread the PDF the other commenter posted, and it's making more sense....I still have much to learn this..
You all are great and I appreciate your help.
I would still be like to have a Mach Guru check my machine over and offer advice and pointers. 😁
Will to buy lunch and time. 😉
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Ok, Gerry.
I changed the settings as you suggested.
I ran a 3d roughing pass, that seemed fine, and now my finishing pass is missing half the model. The bIt is rising 1/4" above the material in spots.
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Sounds like your machine is losing steps in the Z axis.
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What about the CV Dust Tolerance setting?
I only have a check mark in the "stop CV on angles" checked
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Like I said, I turn them all off.
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Thanks again Gerry.
And what about Look ahead? Currently at 40
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Hi,
CV is all about trying to keep your machine going as fast as it can as long as it can.
When it comes to a corner it rounds it a little in order to keep up its momentum. The thing that BEST allows
a machine to follow a toolpath, with corners especially, is acceleration.
Have you tuned your machine to have the maximum acceleration the steppers can manage? It might even be worth turning
the maximum speed down a bit if it simultaneously means you can turn the acceleration up.
Craig
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Thanks for the reply Craig.
I think I am beginning to understand how it all works together, but I am having troubles mashing it all together and getting it to work. I still have problems creep up that I can't figure out. I wish I knew a good series of tests or procedure to do the motor tuning to get it functioning as it should.
Now I have a hesitation well cutting a 4 inch circle as I increase my speed the hesitation gets more pronounced it occurs at the 12 o clock, 3 o clock, 6 o clock and 9oclock.
I am cutting a 4-inch square with a 4 inch circle inside of it and a triangle with a 2 inch radius inside the circle all of my measurements are good and spot on. The tool path will cut the triangle move up to the top and start the circle at 12 o clock and it goes very smooth to three where it will slow down go through that position speed back up to six and slow down and so forth.
At 75 I p.m. I can't notice it at 100 it starts to show 150 200 + 250 it becomes more pronounced. It is a smooth hesitation
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Mach3's trajectory planner is far from perfect.
I've seen hesitations between tangent moves, when there should be none. And I've cut identical parts where it hesitated on one, but not the other.
If it's not a g-code issue, there's probably little that you can do about it.
Mach3 also has no control over the actual path deviation. So when you tell it to go as fast as it can, there's no guarantee how close it will follow the path when it changes directions.
The various controls basically just let you specify a distance from the corner where Mach3 should slow down.
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Thanks Gerry