Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: woodguy7777 on February 07, 2012, 07:46:51 AM

Title: cutting uniform mortise in wood
Post by: woodguy7777 on February 07, 2012, 07:46:51 AM

i have been cutting a 1x2 inch mortise.
at  1 inch per min.  but i am not getting a uniform cut.
just wonder what adjustment i can make to correct this.
thanks paul

Title: Re: cutting uniform mortise in wood
Post by: Hood on February 07, 2012, 09:41:53 AM

Do you have backlash?
Hood

Title: Re: cutting uniform mortise in wood
Post by: woodguy7777 on February 07, 2012, 09:54:27 AM

Are you referring to mechanical backlash.
like play in the drive gears ?  i will check to see if there is any play there
can the velocity and acceleration setting cause this
thanks paul

Title: Re: cutting uniform mortise in wood
Post by: Hood on February 07, 2012, 11:33:09 AM

I am not sure exactly what the issue is, it does look in the pic that opposite corners are much more rounded than the other two, is that the problem?
Hood

Title: Re: cutting uniform mortise in wood
Post by: woodguy7777 on February 07, 2012, 12:45:03 PM

yes hood that is the problem.
the problem seem to happen when the bit goes around the corners
so i am not getting a clean rectangle.
i seem to have this problem anytime i am cutting out a small area.
if i was cutting out a 12x12 area its ok.
it seem as if as the bit picks up speed on the 1 inch side it then suddenly does int the curve  and that is what cause the problem.
thanks again paul
my backlash is set to 20 percent
shopbot cnc stepper motors

Title: Re: cutting uniform mortise in wood
Post by: Hood on February 07, 2012, 02:06:51 PM

Not sure on backlash settings with the PP as I have never used them but certainly seems like backlash to me.
Hood