router bits and chipping

[Dave Bagwill]

Correction: I use the LMII binding bit and bearings.

[John Parchem]

From the wide parts of the bouts always go down hill. That is the way I do it. Also during a climb cut on the tail of the guitar HOLD ON. Do not let the router run. I used all sorts of fancy binding jigs but went back to the LMI bit and bearings in a binding jig. I like that the bit and bearing are on the same shaft.

[Hans Mattes]

My router is also "bit side up" and I hold the guitar by hand as I move it around the spinning bit. The way I remember which way to move it is by always running "downhill" with regard to the grain lines. Each time a cutting edge on the bit takes its tiny bite, it will try to chip out more wood than the bite deserves. So if the previous bite has shortened the "uphill" section, any chip will be very, very tiny (as in, not visible). If, on the other hand, I should move the guitar so that the spinning bit bites "uphill," it has a chance to make a tiny bite into a visible chip (or a VERY visible chip). This mental model works for me. Trying to view a drawing with "circles and arrows and writing on the back" would be distracting while I'm trying to hold the guitar against the guide. As an aside, I cut my binding channels with a rig inspired by Ken (RIP), still using a (now rather modified) Grizzly trim router.

[peter havriluk]

Hans, I also use a binding channel router table that Ken sold me. I've used it with a HSS bit, and the last time I used it I thought the cut was fuzzier than earlier ones. Any idea of how much life a router bit has before retiring it?

Thanks!

[Herman]

Dave, the direction of the cuts are correct. Whether the router is rotating clockwise or counterclockwise.
What matters is that the cut is made from the perimeter towards the centre of the plate.
That way the fibers are not dragged from each other , but instead more compressed.

BTW, A luthier around here told me to use HSS metal bits to prevent chipping, and not HM bits.
Don't know if that is a true.
Herman

FWIW Dave: my latest OOO is going to have a sunburst, 'cause the top has some chipping of the top.
Feeling better now?

[Dave Bagwill]

Thanks homies.

Herman - the LMII bit and bearing system - which I use - states : "The cutter is a specially designed 1" router cutter with carbide cutting tips."

Is the carbide equivalent to HSS?

Building is a fun challenge for me except for two things.


1. After completing neck construction, fretting, making the bridge, the saddle, the nut, the box closed and then - using a small blade spinning at 100K rpm to try to cut a perfect rabbet on a body made entirely out of curves, when the blade can undo all your labor in way less time than the blink of an eye.
2. Even if that is done perfectly, then the finish has to be perfect.

And neither of those things has an effect on playability or tone.
But we build for playability and tone.

Simple but acceptable finishes - such as tru-oil, or a wipe-on finish such as John used on a Uke build - can ameliorate some of the anguish of more complicated techniques - for me, at least. I like the high gloss that some of you get on your gits, but it's not something I care to do.

As to binding - I'm working on it.
Still, a very enjoyable hobby.

[Herman]

Carbide tips are HM style. HSS is ordinary steel drill metal. The cheap ones.
(But I cannot find such a matching HSS bit one for the SM Binding bearings.)
So I deal with the SM cutter. Which is tungsten carbide-HM metal.
Herman