I’m trying a pretty big project in 1/2" baltic birch plywood and it’s not going great. I initially did it with a regular 1/4" upcut bit and the tearout was bad enough to scrap the project. I did some reading and decided to try a compression bit. I just got done with an attempt, and so far I cant even finish the run.
The issue is, for the compression bit to work properly you have to take a deep enough bite for the downcut portion of the bit to get into the surface. On my whiteside bit that look like about .25"
So, I set the DOC to .25, speed to ~18000 and feed to 40ipm and went for it. I found out real quick that either I’m way out of line on something or the machine just plain doesn’t have enough ass to get the job done. It cuts clean, but I can see it deflecting and I keep losing steps, especially on the Z axis.
I tried adjusting the feed all the way from 4ipm to 40ipm, and tweaked the speeds a little, but nothing seemed to help much. The cut is nice, but the chattering and deflection are still present with all the settings I tried.
I’m fixing to try separate upcut/downcut tool paths and do this in two parts with some tool changes. I’m just wondering if anyone else had much success with these compression bits - and if so, how? It seems like the obvious answer is a shallower DOC, but at that point it seems like you’re just using an overpriced upcut bit.