Machining stock to a soecific thickness

[erica (Eric Ahrens)]

I read many previous posts on this subject and am still a bit confused.

If I have stock that has been flattened and want to use my CNC as a planer what is the process?

As an example, I would like to have my stock be .75 inches thick

I am setting Z off the bottom. Can I set a pocket cut to T- .75? Is there a wildcard for Z or bottom?

[mhotchin (Michael Hotchin)]

You already have the right idea:

• Z Zero should be bottom of stock
• pocket depth should be t-0.75
• in your project, set the stock thickness to the thickness of your thickest piece of stock.

If you use this on a piece that is thinner, then you will get some air cutting. You can decide if the air-cutting or updating the file is more annoying.

[WillAdams (William Adams (Carbide 3D))]

See:

Preparing rough cut lumber for machining

Given a rough piece of stock: [20240204_151557] one sets it on the machine, and if need be, adds shims where/as needed to make it as level as possible. and clamp in such a way that the entire top may be surfaced off [20240204_155540] set zero, then begin cutting: [20240204_171001] After running the file once: pocket_464x116_1mm_LOWERLEFT_TOP.c2d (44 KB) if a repeat is necessary, jog down to zero, then down by the cut depth of the file (1mm) set zero there and repeat — the zero may be …

If you still have difficulty, please post photos of the stock you are having difficulty with, the file you are trying to make to cut it, and let us know how you are setting zero relative to it.