Router Bit Search

[Cameron Petersen]

In His fine book on Classical Guitar Building, Mr. Bagdanovich references the use of a flush-cut, top-bearing, router bit, for routing out the tuner slots. He mentions the use of a 3/8 inch cutting diameter bit.

It would have to be a flush-cutting, top-bearing, bit having a cutting depth of about one inch for use with the tuner/peg-head template.

I've been searching all the suppliers that I'm aware of.  Nothing yet.

 

Does anyone know where I can get one???

thanks

[Paul Breen]

Here is one source for them. There is a 5/16, no 3/8 listed and the 5/16 has a 1/2" bearing. You would need to adjust the template for the offset but it could work.

http://woodworker.com/cgi-bin/FULLPRES.exe?PARTNUM=129-614

[Cameron Petersen]

I've seen this bit. Probably get one as a last resort.
What do you think of this?
There is a bit available with a 1/2 inch cutting depth. Would trimming to the maximum depth of 1/2 inch, using the template, then, removing the template and trimming the balance of the depth of the slot be feasable? I envision a slight parting line around the perimeter of the slot. Does this make sense????
thanks

[Russell Vance]

Didn't notice this post before - you can keep going down past the template and use the newly cut surface as a bearing guide (we did this a lot when we used to use hand routers) - no need to remove the template and any lines are fine and easily sanded out.

Don't plunge cut deeper than the radius measurment of the bit - ie: 1/2 inch bit = 1/4" depth of cut (general rule for average bits) and use a number of passes to achieve the cut depth required. Rusty.

[FRANK]

TRY ACE HARD WEAR ?IT WORKS FOR ME

[Mike Kolb]

Take a look at this router bit from Grizzly (#C-1010Z) and see if it fits the bill or not... just add the bearing on top.

http://www.grizzly.com/products/2-1-2-Double-Fluted-Bit-1-2-Shank-3...

[Cameron Petersen]

Thanks Mike.
It dawned on me earlier about whether or not I could put the bearing and collar on top myself.
Any caveats??

[Russell Vance]

No, there is normally a small step (about a mm) between the cutter platform and the shank that the internal bearing 'race' sit on which gives it some standoff from the cutters. you need to allow for this when using thin templates but that's about all. Router cutters come with a bearing and collar clamp for pattern following (template) bits and also come without them so you can keep replacing the cutters without having to stump up for new bearing hardware. If you are using a previously used router bit you may have to dress the shank to get the bearing on as the internal dimensions of ball bearings are quite fine and burrs and scrapes on the shaft will impede the bearing - do not push on the outer race of the bearing to force it on - you need to put a sleeve on the inner race to push down on the bearing otherwize you will damage it.

The bit I use is a 3/8 OD x 3/4" cutting length template follower (part number TB212 B) supplied by Carb-i-Tool in Australia (available on line) - these long bits with the 1/4 ID x 3/8" bearing are hard to find and I have checked my US sources (Router Bit World, Holbren, Whiteside and Vortex ) to no avail for a pre-packaged bit. CMT, likewize do not do this configuration. Grizzly has a ton of chinese bits which are OK for light/occasional use - but getting the correct bearing may be an obstacle.International postage from Australia is cheap - Carb-i-tool is good professional stuff and cheap due to the exchange rate. "http://www.carbitool.com.au" target="_blank">www.carbitool.com.au

[FRANK]

so Russel you prefer this set for the Bering ?

[Jeff Highland]

You are going to be cutting 16mm slots so why not use the 1/2"bit and 1/2" bearing combo

[Russell Vance]

Probably because this requires a plunge router bit and plunging a half inch bit is more difficult in this situation than a 3/8 bit. Technically it's OK to use the bigger bit; practically, it's probably easier and safer to use the smaller diameter bit.
The second issue here is starting the cut with a thin template and unless the template is stepped off the face of the peghead the initial cut will require freehanding the bit until the bearing lines up with the template - smaller bit is a much better proposition here - a deep template (you can '1 to 1' copy from your original template) is a better idea.

[Cameron Petersen]

I wasn't very thorough in explaining the problem. The 1/4 inch template is attached to the peg-head, an 1/2 inch forsner bit is used to hog out most of the wood, a chisel is used to clean up the ridges, the the router bit is used to clean-up the sides. thanks.

[Ned Knepp]

It sounds to me like some rasp and file work may do the trick as quickly as setting up for a router unless you plan on doing this a lot. I think you will need to use these to make the ramp into each slot anyway

I have to ask; If you have the slot already made, why be so particular about the size of the bit you use to clean it out?