What am I doing wrong

[bill_moore]

I am trying to cut some Vetric 3D "A" type files to make some appliques. The problem is I can't get them to cut thru my stock. I am playing with 3/4 MDf actually .765 thick. I set up the 3D file with .77 thick model in .77 thick stock thinking that would put the finish cut thru the stock. It did not. So without touching anything I retoolpathed droping the design into the stock .004. No help kept doing that untill I am .020 into the stock and it still doesn't cut free. I know it has to be something I am doing wrong but after 8 hours of trying I am stuck. Any advice would be appretiated.

[scottcox]

Bill,

Reading your description, that should work for you, but it would still depend on where you zero your Z.

When cutting out MDF parts, I often toolpath it as if my material was .75", then I zero my Z to the table surface and then raise it .74", then re-zero my Z. On the final pass, I'm cutting .01" into my spoilboard.

[ryan_slaback]

Bill, are you making sure to re preview the toolpath? If you change the toolpath but do not preview the new toolpath it will leave the old image on the screen

[bill_moore]

Thanks Scott & Ryan. Ryan I did preview some of the time but not every time. I retoolpathed rough and final then saved the file as a different name. Then went to partworks deleted the old toolpaths and image then brought the new one in. I did not know the preview would matter. I finally did a cutout toolpath just to get it out of the blank. I had to set the leave material block to -.021 to get it to cut out.Just scratched the spoilboard. I did find that when I z-zero with my plate which is .120 thick and set in shopbot setup then drive it back to zero at that same spot I can slide a .006 feeler gage under it.