What router bit to use?

[tdale]

I'm making a fretboard routing jig for my table mounted router. I have two bits that will work, one 1/2" straight bit and one bottom cleaning bit, with 1 1/2" diameter. Which bit will be the best for the fretboard?

I also have a jig for the contouring of the neck back. Which one is best for that?

Tommy

[Ripthorn]

Are you talking about radiusing the board? If so, either is likely to work just fine. For finer contouring the back of a neck, I would go with the 1/2".

[RogerC]

*edit*

I wasn't sure what I was trying to type, but none of it came out coherently at all...

[Moldy Oldy]

For radiusing the fretboard, if you want to use the 1-1/2" diameter bit, just make sure it's not going to take out part of the headstock when you are routing up by the nut. It seems like it would be ok, but just thought I would mention it.

----------------
Dave

[tdale]

Thanks!

[Shepherd]

If you can find one of these it will give you a nicer finish with less sanding compared to a straight bit.

[guitarbuilder]

Using a straight bit for fretboard radiusing will produce a faceted surface that just needs to be cleaned up with a scraper and abrasives. A roundover bit will leave ruts that will require more work to clean up afterward. I used a homemade jig with a straight bit for years and now use a roundover bit in my cnc. The straight bit took about 90 seconds to do the the board. The roundover requires many more passes because it leaves a scallop.

[SFenn]

^ What he said.

[guitarbuilder]

And I find that a roundover seems to compress the fibers more as opposed to a straight bit.

[Shepherd]

It's the same as a straight bit except it has rounded edges. Works great for me.Try a better bit.

[kwerk]

I think that's a bowl carving bit as opposed to a cove bit, isn't it? I'd say that would be ideal for fretboards.

[guitarbuilder]

Originally Posted by Shepherd

It's the same as a straight bit except it has rounded edges. Works great for me.Try a better bit.

I use Freud.... I think it has to do with the straight bit doing more of the work more efficiently. I use the cove one you posted first in the cnc. When I was shaping my necks with a router, I used a bowl bit and those worked well there too.

[Nick JD]

I use a 1/2" diameter straight bit for fretboard radiusing. Works fine.

[Davecam48]

Originally Posted by Nick JD

I use a 1/2" diameter straight bit for fretboard radiusing. Works fine.

Hear hear!

Just move it across the job in small progressions.

[RogerC]

I tried using a straight bit when I first fabricated my jig. It came out very poorly despite taking pretty small passes. I think it had more to do with my jig, though. I've still not gotten it dialed in, but am contemplating the next incarnation to make sure things are true.

The plan is to use 1/4" aluminum and have my end radius pieces cnc'd. I'd love to have the box fabbed from aluminum as well, but I can't justify the cost of a solid chunk of aluminum that large. I think once I get the end pieces made, I'll just spend more time with better materials to fabricate the box and rail assembly.

[guitarbuilder]

Originally Posted by RogerC

I tried using a straight bit when I first fabricated my jig. It came out very poorly despite taking pretty small passes. I think it had more to do with my jig, though. I've still not gotten it dialed in, but am contemplating the next incarnation to make sure things are true.

The plan is to use 1/4" aluminum and have my end radius pieces cnc'd. I'd love to have the box fabbed from aluminum as well, but I can't justify the cost of a solid chunk of aluminum that large. I think once I get the end pieces made, I'll just spend more time with better materials to fabricate the box and rail assembly.

Roger, you might try building this one first. It was made from mostly poplar plywood and worked so well I never made another one.
http://luthiersforum.com/forum/viewt...+radiusing+jig

[RogerC]

I've seen that one over at the OLF, but it doesn't allow for doing compound radii. The one I'm building really is quite simple, but I just didn't take enough time fabricating it.

I probably just spent way to much time doing this sketch, but here you go . You'll then have your rails running between the end pieces, and a sled to hold the router. The rails go over the ends as the sled runs back and forth.

[tdale]

Here is my fretboard radius jig (haven't tried it yet).

It's based on the one that was linked to in this tread, and a couple of other designs I've seen, like Bill Scheltema's design.

The main difference is that it's made for a router table. I'm not sure if double sided tape will be enough to hold it in place, but if not, I can use a screw in the heel, and some kind of metal bar across the headstock, to hold it in place.

I added some plywood in both ends, to keep the neck in place, so I think tape will be enough..?

Tommy

[Mightyaxeman]

Originally Posted by tdale

Here is my fretboard radius jig (haven't tried it yet).

It's based on the one that was linked to in this tread, and a couple of other designs I've seen, like Bill Scheltema's design.

The main difference is that it's made for a router table. I'm not sure if double sided tape will be enough to hold it in place, but if not, I can use a screw in the heel, and some kind of metal bar across the headstock, to hold it in place.

I added some plywood in both ends, to keep the neck in place, so I think tape will be enough..?

Tommy

No tape will not be enough. Come up with some sort of clamp configuration.

[tdale]

OK..

I'll try on a piece of scrap wood the first time anyway... The neck will be held very firmly in place sideways, but the tape is quite thick, so I guess it could compress a little, causing the fretboard to be curved...

Tommy