I’m doing a fairly large (18" x 18") finish pass on a model that is 1.75" thick. I realized that as I approach the outer portion of the cut, which is @ -1.5", that the collet is going to be way too close to the waste material and grind against the sides.
My initial thought was to note the line number of the finishing program, stop the program, replace the 1 mm bit with a 2" surfacing bit and grind down the outer perimeter about 1" then reinstall the 1 mm TBN and continue from the line # noted above.
I then realized that I wouldn’t be able to accurately set the Z0 again when I reinstall the 1 mm bit so the carve goes smoothly without any obvious depth difference.
I have a tool setter installed, but not activated.
My question is, if I activate the tool setter, reboot the controller, how can I accurately reset the Z0 to my original position? Is this possible? If I don’t activate the tool setter how can I re-zero the 1 mm TBN accurately, after using my 2" surfacing bit?
This is what happens when you don’t think thru all the possible issues that may come to pass.
@Tomdigi
Thomas, do you set your zero to the bed or to the material surface? If the bed, you should just be able to “re-zero” your Z axis when you change bits and continue your cut. If the material surface, will you have any part of your material that will still have the original top surface? If so, you should be able to zero there to set your Z axis after bit change.
In either case, changing the bit and resetting Z zero is the function of the tool setter…mine works great. I’m not sure why you would have to reboot the controller…please explain.
If I go into setup and turn on the tool setter, it does not function until I reboot the controller. At least that’s been my experience. I had previously set up the tool setter and actually cannot remember why I turned it off. I’m sure turning it back on would be the proper way to do this, but I just don’t feel comfortable that I’ll be able to recreate the current z0.
I actually think I’m going to take a whole different approach. I’ve set up a pocketing tool path in aspire using the same 1 mm tool to remove about a half to three quarters of an inch using that bit. I won’t have to reset zero at all.
It will probably take 2 hours, but without any change in the z axis, and I can go right back too finishing the machining of the project. For me, 2 hours of machining is a small price to pay for an error I created.
Again, as I said earlier, this is all due to poor planning on my part. Should have done this machining of the waste area prior to starting the finish pass.
Thanks for your reply and suggestion. I really appreciate it.
@Tomdigi
Thomas, I did have one more thought for you. Daniel over at PwnCNC sells bit setting jigs that make the process of setting the bit in the collet so it is at the same height a breeze…he calls them speedsetters (SpeedSetter easy Stop-Collar Setting Tool – PwnCNC).
Thanks Jay. I’ll do a little research on that and see if that will help.
As it turned out once I installed the tool path for clearance and ran that, my z0 changed when I went to the jump to line option within the finishing tool path. I ended up having to manually set it, run a few laps around the finish path and then adjust the z0 down in small increments. It turned out very well. Again, thank you