Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: GAK801 on August 14, 2011, 12:35:28 PM

Title: Z Offset issue
Post by: GAK801 on August 14, 2011, 12:35:28 PM
Even though I just recently started using Mach3, I thought I knew what I was doing on setting z work offsets, but that was clearly presumptuous. Previously, I'd use a 0.002 inch shim stock as the gage, but I recently misplaced it, so I grabbed a 0.5 inch gage block to set Z offset. The bit never hit the part and was at least a quarter inch above the part. I reset the offset but entered the gage as being 1 inch thick. I noticed that the z offset value in the DRO only changed by 0.1 inch which seemed odd. The bit still seemed to be about the same amount above the part surface.

So I'm guessing that the previous gage was small enough that I didn't notice the difference. Now I need to make some parts that mate together in places so the 2 mil difference might be a problem.

Is there some other setting that has to be made to invoke the Z part offset?

I can work around it, but would rather understand how to do this properly.

Greg
Title: Re: Z Offset issue
Post by: BR549 on August 14, 2011, 02:17:18 PM
The basic Z offset is the TOM (top of material  OR a standard reference point plus the value  of the guage). In yous examples when you touched off , +.002 for the shim and +.500 for the block. You would enter those values into the Zdro.

From the operators point of veiw it is not an offset but  a setting of the reference point of ORIGIN for Z  Z0.000. The machine uses a different set of coords to keep track of everthing important to position.

Did that help? or hurt (;-) TP
Title: Re: Z Offset issue
Post by: GAK801 on August 14, 2011, 03:15:19 PM
I think I understand. So in the upper left hand region of the offset page (z offset block), I ignore the gage thickness field and just enter it into the DRO field directly, correct?

Greg
Title: Re: Z Offset issue
Post by: Hood on August 14, 2011, 03:19:14 PM
You can enter it direct into the Z DRO on the main page or any other page that has the Z DRO.
Hood
Title: Re: Z Offset issue
Post by: BR549 on August 14, 2011, 09:26:30 PM
As Hood stated you can enter it directly into the Zdro OR use the offset page which will do the same thing as you entering it .

(;-) TP