Compression Bits?

[Howley]

Does anybody know if they make 1/4" compression bits?
I only see them in 1/2" diameter.

I know onsrud and amana are good bits, any feedback of Freud bits?
So many cheapies on eBay, but you get what you pay, any lower price but still decent quality bits I should consider?

Thanks, John

[sawkerf]

R&B tool, Centurion tool, vortex tool to name a few? Great personal experience with the first two

[srwtlc]

All sorts of them here.

Centurion (https://www.centuriontools.com/router-bits-toolcase/solid-carbide-wood-router-bits.html?pcn=Compression%20Routers)

[steve_g]

I once had some 1X1 1/8” compression bits... I don’t recommend them! very fragile.

SG

[garyb]

John
Onsrud produces 1/4" compression in both single and two flue tools. you will also find the 60-111 SE and the 60-113 DE are mortise compression.
you can find the specs and pricing here http://beckwithdecor.com/index_files/ONS23.htm
Gary

[jzarski1]

I use the 60-111 all day to cut MDF. I get a perfect edge on both sides. One bit last me about 100-120 sheets.

John

[Ajcoholic]

I use mainly Onsrud 3/8 single and double spiral compression bits to cut double faced veneered plywood.

I also have a few single flute 1/4" bits (packaged as Porter Cable) I use every once and a while. They seem to cut well, but I dont use them a whole lot, as I prefer the 3/8.

[paul60]

I am looking to cut double sided 3/4 MDF.
using a 3hp spindle .
what compression bit is recomended for this
and at what speed.
will the 1/4 Centurion work
also can i also cut 1/2 inch with the same bit.
2 Flute, Plunge End, 5mm & 1/4" (https://www.centuriontools.com/router-bits-toolcase/solid-carbide-wood-router-bits.html?pcn=Compression%20Routers&pid=791)
thanks Paul

[jTr]

Paul,
The centurions have a good reputation among many of us for doing a great job for exactly what you intend to do. Yes, it will work equally well with 1/2" material . I typically run 4-5ips move speed at about 12,000 rpm with a .25 two flute compression bit, though those values seem to work reasonably well with my Whiteside single flute compression bit.

Most important thing to note: As you toolpath, be sure your first cut depth exceeds .025 into the material - I typically set at .030. This is because the first 1/4" of the tip of the tool is ground to upcut - if that portion of the bit is not buried into the material, it will tear out the face of your sheet. The remainder of the bit is downcut, which is what you want contacting the top of your material.

As the bit is plunged for final pass, that upcut portion is pulling in the proper direction to preserve that bottom face of your material, virtually eliminating tear out.

Some of us plow through full depth in a single pass and do well. If you have the time, I'd recommend 2 passes for 1/2" sheets and 3 passes for 3/4". Easier on your machine, and less prone to shifting of the material if your hold-down method is not super-firm, such as a home-brew vac table.

jeff

[paul60]

Ok got it. i had the impression you had to cut full depth with a compression bit to get the effect
of the up and down cut.
now i see what you are saying about setting your first cut to .030
that takes care of the problem
thanks Jeff

[Ajcoholic]

When I cut 3/4 particle core veneers I use the 3/8 Onsrud single or double flute (single flute works really well actually) and go in one pass almost all the way through climb cutting - leave about 1/16" - and then conventional cut to clear it.

Leaves a GREAT face on both sides. I dont cut a lot of melamine, but I did do a small job (10 sheets of 3/4) recently and cut up the odd shaped pcs the same way on the bot. Again, left a razor sharp edge both faces. Awesome.

My HSD 4 HP spindle can easily cut at full depth without any issues.