Machining 2 3/4'' thick solid oak

[DanFecteau]

Hello all. We have to rout full depth 1 5/8'' grooves in a solid oak 2 3/4'' thick piece. We have a lot to do. Problem I have right now is that I get a lot of vibration due to the tool lenght I think….I'm using a 3/4'' diameter Onsrud 60-277. I have 18 grooves of 17 1/2'' long to machine on each piece, tool does not last more than 3 pieces...and most of all, I thing it's being really tough on our cnc.

Thanks for all advices in advance !

[Jeremy Schiffer]

You definitely need to make cuts like that in multiple depth passes. My rule of thumb is not to exceed the bit's diameter for the depth pass - i.e. you would make 3/4" depth passes. Other than that, it's just a matter of fiddling with feeds and speeds.

As a side note, on solid wood, you'll get less splintering if you do climb cuts.

[Forrest Chapman]

I've done a fair amount of that type cutting and have best results with a 3 flute rougher hogger upshear purchased from Carolina Specialty Tool $275. By a shorter one if you can with less cutting edge. Set the tool as far into the collet without the fluting touching. I usually leave mine an 1/8" out. If you set it below the fluting it will break.

If you need a clean top edge then you will need to run a shallow pass with a downshear first.

Run the tool 16000rpm and upwards of 700 ipm. You can play with that a little but it will cut that fast easily at 3/8" depth passes. If you run it that fast you tool will last a long time.

Depending on what you're using to program with you may be able to do a constant load pocket which can spiral in and then scoop away at the pocket wall a set amount at a time instead of just running the full length at full cut if that makes sense.

Forrest

[Will Williamson]

What are your speeds and feeds on this job. I do this all the time on, solid wood.
I use Vortex tools with down spiral. Chip Breaker, Rougher, or finisher,
adjust tool, for needed edge surface quality. These tools last for all day.
If you need smooth edges, try a 5/8 down spiral rougher, followed by a 3/4, down spiral, finish cutter.
I usually run these cutters at 16,000 rpm, 500 IPM
Make sure you are making chips, not dust.