File editor

[paul60]

i have been using file editor [FE] to edit the thickness of the material. i am using plywood so each sheet vary in thickness. once i know the original
thickness, its no problem i just enter the thickness under find and enter what i need it change to.
the problem comes when i am not sure what the original thickness was.
and i am not sure where to find it on the file
this it the shopbot cut file i am speaking about.
thanks
paul

[Gary Campbell]

Paul..
When using materials of varying thickness' change your Z Zero to the machine bed. Minus a few thousanths if you wish..even if doing multiple passes you will always cut through the material.
Gary

[rob_bell]

Hey Paul-

Here a little shopbot magic I wrote about last year.

http://www.talkshopbot.com/forum/messages/32/20787.html

It's a technique I still use every day. See if that makes sense and I'll elaborate more here when I have a spare cycle.

[paul60]

thanks for all the help.
i decided to go with Gary campbell idea also got help from scott worden.
This works. i now dont have to measure every sheet
there is one other problem. i use a 1/4 inch bit
to drill the shelf holes then change to a 3/8 bit
for the cut out.
how do i now zero the 3/8 bit with the ply sheet on the table?
thanks paul

[Gary Campbell]

Paul..
If you cant switch to doing all your cutting and drilling with the 1/4" bit, write a routine that takes the first bit height on top of the material, allows you to change the bit, rechecks the new height, then calculates the offset for you. You can then cut the file with a Z offset, or have the routine rezero the second bit off the material to the same height as the first.

One more question: if you use the 3/8 bit first to cut through, cant you simply zero the drilling bit to the top of the material? All of our system screws are a consistant depth from the inside face of the sheet.
Gary