I’ve had my Longmill up and running for about a month now and starting to explore the world of bits. I would say 80% of the stuff I do I’m using Baltic Birch ply 1/4" to 3/4" thickness. Anyone have suggestions or recommendations on a brand or what too look for when cutting finished ply? The Spektra bits keep popping up everywhere I’m not sure if they are worth the hype or not.
@DrewBSC I have seen Amana’s Spektra bits, but having never bought one, I can’t say anything about them.
I, too, cut quite a bit of baltic birch plywood from 5 mm up to 24 mm. I just use the Sienci 2 flute end mills, both up cut and down cut. The results are good. Mill life seems to be reasonable, too.
Thanks Grant @gwilki ,
I’m having a real hard time sorting out the feed speeds / rpm / depth of cut with my 1/4" bits. I am using the bits that come in the Sienci starter pack, most of my issues is when the machine is cutting from right to left, im having a little bit of chatter. Are you willing to share a couple numbers?
@DrewBSC As a starting point, I use this chart:
It’s pretty conservative, but you can always speed things up on the fly using your gcode sender of choice. (gSender surely )
Assuming that you are cutting out shapes and not pocketing, you may find that you get better results with a 1/8" bit. Our Mills do not really travel fast enough to get a good chip load with a 1/4" bit. (I’m ready for people to disagree. ) If you are cutting out, you don’t save any appreciable time using a 1/4" bit over a 1/8" bit. It’s a different story, of course, if you are pocketing.
Keep in mind, too, that plywood beats the heck out of our bits. In baltic birch, there are many layers = a lot of glue = a lot of abrasive.