I’m really trying to search and do my due diligence. And get all my dumb questions out. Workbee, lead screw, black box, fusion 360 for CAM I have a very specific part to machine. Setting up tooling on spoil board. All my pockets, or holes are undersized. About .03 inch. Location is spot on! So calibration looks fine. I’m not leaving any stock. So from searching looks like it could be feeds and speeds or a setting in post process. FYI using a 1/4 Endmill to make a .375 hole. No pin gauges but my micrometer is .355. Not to muddle post. But plan is to machine 2 sided 3D parts. And they do not mirror. Thinking my zero is safe at the home position?? Can home before every cut?? Or is this a bad idea? Hopefully getting to end of dumb questions....
material being cut? this is quite normal, due to tool pushoff. a micrometer will always under read on small holes because the edges of the inside jaws are little flat spots (not so little in the case of my cheap calipers :- ) no, home is not/never 'part zero'. in fusion you set part zero in the setup. for 2 sided stuff this is normally one of the locating pins.
Thanks for the feedback. I’m machining my spoilboard for hold-down locations and some indexing slots. So it’s MDF. The holes are for 3/8” pins. I’ve seen the posted video. So I’m guessing I should have done a drilling path, then just used 1/4-inch pins? I’m using a 1/4 tool I modeled the spoilboard. So for zero for this I did use the homing location. And I get your point, when I start running parts I’ll have a different zero. Still researching that one.
There's no drilling cycle for GRBL, so unless you are using control software that can do the conversion for you, then no. No mater what machine you are using, its common place to have to walk in the diameter of holes being used for pins. You do this by adjusting the radial stock to leave. Lets assume your .355" measurement is correct. You'd want to set your radial stock to leave to -.010 to get the .020 you are off by. However, its smarter to take shallower cuts and sneak up on the fitment.
Another thing to check with the micrometer is your endmill diameter. I have yet to find one that is exactly what the manufacturer states. For example, I have a Freud 2 flute (straight flutes) 1/4 inch router bit I use for cutting wood parts since the straight flutes cut clean with no chipping or tearing like an up-cut bit. This bit is really only 6.11mm vs the expected 6.35mm, so any hole I make, or pocket I cut would be undersized if I told the CAM software my bit is 6.35mm.
^^^^ THIS. I bought the same router bit and learned the hard way to check my bit diameter. Especially when using a bit from a new manufacturer on an old job.
Oops! I should have mentioned that when I suggested the bit. Sorry. I first discovered this problem with cheap Chinese endmills and things wouldn't fit together.
