Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: eforer on August 22, 2012, 01:31:23 PM

Title: axis acceleration
Post by: eforer on August 22, 2012, 01:31:23 PM
We retrofitted our Multicam cnc router to mach 3 some time ago after finally losing it with multicam support for the electronics, pendant etc.  One thing we have struggled with the whole time with this machine has been issues with chatter and cut precision when changing direction.  I discovered that while the motors weren't stalling, the accelerations have been too high creating shake in the spindle during abrupt starts and stops.  Is there a formula to figure out safe minimum acceleration speeds for a given feed rate.  We never cut much above 150 ipm.

Thanks!
-Ed
Title: Re: axis acceleration
Post by: Hood on August 22, 2012, 02:17:42 PM
Not reallyas it will all depend on the particular machine you have and its rigidity.
Just wonder however if you are possibly in Exact Stop mode (G61)? If you are then changing the Constant Velocity (G64)may help you a lot as it will not stop at the end of each line of code before starting the next.
Hood
Title: Re: axis acceleration
Post by: eforer on August 22, 2012, 03:21:36 PM
I'm using sheetcam's mach2 post.  Where would I expect to see a G61 or G64 in my code?
Title: Re: axis acceleration
Post by: Hood on August 22, 2012, 05:21:17 PM
You would likely see it on the first line or two of the code. If it is not there then what its set to will depend on how Mach is setup on General Config page as you can set the default there. Each time Mach starts it will default to that but it can be changed by code so it is always good practice to set modal states in your code.
Hood