Question about pattern bits.

[Dick Holt]

I need a pattern bit . Eagle America has a 3 flute bit without downshear for $27. They have a 2 flute with downshear for the same price. They also have a two flute solid carbide spiral bit for $75. Which bit would do the best job (smooth cuts with least amount of tearout)?

Dick

[Bill Huber]

My Go To pattern bit now is a 2 bearing bit, bearing on top and bottom. This way I can flip the item over if the grain is going the wrong direction. I have some other pattern bits but they just have the bearing on top and they stay in the drawer most of the time now.
This is the bit I have now and so far it has done a very good job.
And yes get a shear type bit, they are much better than straight bits.

http://www.toolstoday.com/p-5888-down-shear-multi-trimmer-router-bit.aspx

[pat warner]

None of the above if they all have .50" cutting diameters.
Get a cutter/trimmer that starts at .75" +CD. Anything <5/8" CD has too much grinding into the shank = deflection, chop, resonance and a hammer finish.

[glenn bradley]

I'm with Bill on upper/lower being the best bang for the buck. The spiral will probably give the smoothest result but, I was once told to use the largest diameter that I could. I do find that when the pattern will allow, my 2 flute 1-1/8" bit gives the smoothest finish of all the variations I have. If the curves are tight, my 1/2", three flute downshear beats my 1/4" spiral for smoothness so maybe that will help you judge. In short I would run the largest shear bit you could and still follow your curve.

[Jeff Monson]

I have a whiteside 2" pattern bit with top and bottom bearings, I have great success with it.

[Myk Rian]

I have a Freud with top and bottom bearings. Nice bit.

[Jerome Hanby]

my 2 flute 1-1/8" bit gives the smoothest finish of all the variations I have.

I see the same thing. Dumb luck I bought that one first for a project that had me doing a lot of pattern routing. After getting other, smaller pattern bits, I still go back to the big one whenever the task permits.

[Dick Holt]

Thanks for the replies guys. I just ordered a 3/4" dia. double bearing bit with downshear (Amana Tool).