pattern bits

[keith ouellette]

If you were only going to have one size pattern bit what size would you get as far as the diameter?

I am looking at a top/bottom bearing bit with a 3/4" diameter and a 2" cutting length.

I figured with a 2" bit I can cut anything up to 2" where a shorter bit would be limited to less, no brainer there...

But as far as the diameter is 3/4" what I would use for most patterns and in what way am I limited with a 3/4" dia?

[Bill Huber]

I am not sure if it make that much difference in the size, the only thing it would do is cut down on the small inside radiuses you cut. I will be looking for other comments on this.

The trim bit that I use the most and really like it, is the one from Eagle, its a shear cut, I have a spiral one but I like the shear better, the one I have is 3/4 inch.


http://www.eagleamerica.com/product/v117-0842/ea_-_laminate_trim

[keith ouellette]

I am not sure if it make that much difference in the size, the only thing it would do is cut down on the small inside radiuses you cut. I will be looking for other comments on this.

The trim bit that I use the most and really like it, is the one from Eagle, its a shear cut, I have a spiral one but I like the shear better, the one I have is 3/4 inch.


http://www.eagleamerica.com/product/v117-0842/ea_-_laminate_trim



Bill: I saw that bit. I like the shear angle but I want one with a bearing at the other end. I don't know which end is considered the top/ bottom.

When i found ones with a bearing at each end i decided on it but I cant find one with a shear angle.

[Vince Shriver]

Infinity has them: Double Bearing Pattern Router Bits

http://www.infinitytools.com/Double-Bearing-Pattern-Router-Bits/products/1336/images/1336.jpg
Template guided pattern work is one of the most common routing applications and these new pattern cutting router bits perform perfectly with the template above or below your workpiece. With a smooth cutting shear angle and an upper and lower guide bearing you can choose which side to mount your pattern on for maximum efficiency. Our Double Bearing Pattern router bits comes with two bearings, a bearing stop collar and our small hex key.
ItemShankLarge Diam.Carbide HeightDown Shear Low PriceOverstock
PriceQuantity06-127B 1/4"1/2"1"Yes$22.90 06-690B 1/2"3/4"2"Yes$34.90

[Chip Lindley]

Hi Keith! If you must only have ONE pattern bit, make sure it's 1/2" shank! Especially a Long one. The smaller the cutting diameter, the less chance that an unbalanced bit will feel like it is going to expode out of the collet! I acquired a $10.00 (1/2" shank, 3/4" dia. 3" cut) bit with top and bottom bearings. It will barely stay in the router! An eBay search found a 1/4" shank, 1/2" dia. pattern bit with a 3" long cut! WOW! Scary!

IF I had to pick one bit, it would be 3- or 4-flute (to minimize tear-out in solid wood), 1/2" Dia. with 1/2" shank. Maximum cut length of 2". As a safe rule of thumb, the shorter the bit length, the more stable it will be. And, with cheap-o bits you get what you pay for. Invest in a name-brand and spend the $$. Better Balanced and Better Carbide!

[mark kosse]

If I could have only one, a 3 blade 2" long 1/2" dia with a 1/2" shank would be it for me. I also like the bearing on top. It keep the blades a little farther away, assuming your using it on a router table.

[Keith Christopher]

I use a dbl bearing whiteside spiral. Very clean cuts and accurate.

[keith ouellette]

Thanks for the advice everyone. I will be ordering tonight.

So far I decided on the one vince pointed out from infinity which has a down shear, 3/4" dia, 2" cutter height, 1/2" shank, top and bottom bearing.

I like the idea of a shear angle and at $34 plus shipping it seems like a lot of bit for the money.

I was told by someone at Infinity that all 1/2" pattern bits come with a 1/4" shank. I would have thought they would narrow the shank down at the point where the bearing is to accommodate a 1/2" bearing but I guess not.

[johnny means]

I would have thought they would narrow the shank down at the point where the bearing is to accommodate a 1/2" bearing but I guess not.

They do not do that because they would have to some how get a 1/2" bearing around the middle of a 1/2" shank. even if they could pull that off, you would still have the issue of a 3/16" "waist" in the middle of your bit.

[pat warner]

A little spooky for this teck. The OAL of these tools is typically 3.5 -4.5", very long for hand or table router use.
Notwithstanding, using the shank bearing has the entire cutter in your face (extended), even when you're routing skinny stock. On the other hand, using just the bottom bearing has the motor casting as high as it goes, unstable top heavy router now. So working modestly or at the max there are safety trade offs.
Moreover, a router tip with the shank bearing in play could spoil the templet, work, you or all 3 of "youse".
In my view, routers have no business trimming stuff much >1.5". This (your 2" fluted tool) cutter is just plum dangerous.
Plunge routing with collars, tho with its problems, is still a better safer choice for thick-stock hand pattern routing. You can use a cutter sized for the work, in any increment you choose, the collar protects you, the templet etc. from a cutter accident, bottom cutting is available (not so with your mile long tool) and short increment stage routing requires very little horse power. Tho not for everyone, wasting the full thickness in stages is easier on the router, cutter, you and is a safer way to templet rout whence hand routers are called for.

[Stephen Edwards]

Maybe there isn't a "one size fits all" pattern bit. I bought a router that came with a set of the cheap 1/2 shank yellow bits....I think 40-50 bits. There are 3 or 4 pattern/slush trim bits in that set. I've used them a time or two, enough to know I wanted a good one.

I bought a 1" diameter Whiteside top and bottom bearing bit. It's either 1 1/2 or 2" cutting length. I forget. It works fine for most of the pattern work that I do. When I use this bit it's always only removing a small amount of wood. I either bandsaw or scroll saw just outside the line of the pattern and use the bit just to clean it up. Not much stress on it that way.

[Karl Brogger]

If you were only going to have one size pattern bit what size would you get as far as the diameter?

Whatever diameter comes with insert cutters. The rest are too expensive. I think I bought a box of 20 replacement cutters and they were $1 a piece, double sided. I can't have them sharpened, not that I'd want to then it no longer cuts flush, for what replacements cost. I think I paid $80-90 for mine five years ago.

http://www.amanatool.com/bits-fv/rc-1000.html

There's also a top bearing version.

[glenn bradley]

I prefer top and bottom bearings because I don't generally use a pattern bit on straight things. On straight or gently curved slopes I'd just use a flush bit. Top and bottom bearings allow you to always route "downhill" to avoid tear-out on shapes that move from long grain, past end grain and back onto long grain.

The larger the bit the smoother the cut is something I read in a review and it has proven to be true for me. This does not hep you though if you need to get into a 1/2" radius curlicue. In general I reach for the largest diameter bit that will do the job. All these have been used for one thing or another:

135404

I also have a 1/4" diameter flush bit in the Colt from a sign I was doping the other day. Sadly there is no one answer to this question. If I could only have one; I would try to guess what the smallest area is that I would have to get into and get that size. It would wear out fast though because I would be using it for . . . everything.