Calibration???

Post by **Biotech1** » Sun Apr 13, 2008 8:44 pm

Hello, I was needing the great minds of the vectric forum. I did four progs for calibration 2 one inch squares and 2 one inch circles 2 pocket inside 2 outsidevectors. Now when I did the square and circle pocket i was .9998 from on inch and when I did the profile outside i was 1.148 of
on both was wonderinf if anyone had any idea why it is off

Post by **Paul Z** » Sun Apr 13, 2008 9:44 pm

I'll just comment on one cause and that is the bit and how it cuts.

First, many bits are not their advertised diameters. Check it with dial calipers or such.

Second, no chuck and shaft are perfectly coaxial. There is always some runout.

There are also drive issues but you didn't mention what you are using for a machine.

Paul Z

Post by **knighttoolworks** » Sun Apr 13, 2008 11:08 pm

could also be bit flex did you do a regular or climb cut?

Post by **HoustonFirefox** » Wed Apr 23, 2008 5:48 am

If using Mach 2/3, I wonder if the number of steps-per-unit might not be off (inches/mm)?

I would try Knight's solution first and run some pure G-Code to double-check the accuracy of the machine.

Post by **TReischl** » Fri Apr 25, 2008 2:06 pm

.148 is a LOT, especially since your pockets were almost dead on (.0002 is dead on in my book).

I would check things like:

Did I cut on the wrong side of the line?
Was cutter comp active and on the wrong side?

I sure would NOT be worrying about spindle runout. If your spindle was running out that much, I would get a bullet proof vest before I turned it on.

Good luck!