How easily should a spiral upcut bit plunge?

Question

I bought a 3/8" spiral upcut bit to create mortises. While making a few trial cuts, it seems to me that the bit does not readily "drill" into the wood and there is usually some burning while plunging. I'm wondering if this is normal, or should the bit easily plunge onto the wood?

I've been trying this with poplar and pine. The router is a Bosch 1617 with var speed. The bit came from MLCSWoodworking.com

If I want to make a 3/4" deep mortise, how many passes should I need. (i.e 3 passes at 1/4 inch deep each pass). Or should I be able to make the mortise in one pass?

Thanks for any info or recommended techniques.

Mitch

Leon · Accepted Answer

A better brand bit should yield better bits and FWIW a 3/8" end mill bit typically works better.

CW · Answer

It should plunge quite well. No burning should happen. Sounds like you havea defective bit there. 1/4" per pass is about right.

Mort Stevens · Answer

It should drill without too much effort. But, not all spirals areintended to be plunged - make sure the one you have is intended formaking plunge cuts.Mort

J. Clarke · Answer

An upcut bit should pull itself into the wood (I've had them pullthemselves right out of the router).  Are you _sure_ it's not adowncut?

pat · Answer

Would still be advisable to sweep & plunge simultaneously at ~ 1/8 -3/16/pass.Some talk about morticing at the link:*************************************

Jim Weisgram · Answer

[...snip...]Some bits don't have cutters at the bottom. You can drill a hole to bea "starter", then use the router bit. I'd drill the hole near but notright at the end.

Andy · Answer

I did the same thing - I got a 3/8" solid carbide spiral upcut by CMT (at $50+, one of the more expensive bits I own). It plunges and cuts mortises with no hesitation or burning - I think I did 1/4" - 3/8" deep per pass. Highly recommended mortise method, though I'd probably look for a solid carbide end mill in the future to save some $, as per recommendations from this ng. I've had good luck with MLCS bits in the past, but maybe their spiral bits just don't "cut it". (Sorry, couldn't help it...) Is your bit solid carbide? If not, that should make a big difference. Good luck, Andy

How easily should a spiral upcut bit plunge?

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