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I just completed the prettiest BRW bridge I've ever made and now I have to ask for some help in order to make it work. Unfortunately, the saddle slot is wider (about .135") than the .125" stock I have on hand. I now need a wider saddle to make it fit and compensate for the error I made in routing the slot. Since I don't plan on repeating this mistake in the future, I only need one.

I was hoping that someone might be able to sell me a wider saddle blank. The minimum dimensions I need are as follows:
3"L x .400"H x .140"W

I would be most grateful if anyone has wider saddle stock and can spare one. TIA

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JJ
Napa, CA
http://www.DonohueGuitars.com

Check with sone knife supply houses for Bone handle blanks typicaly 3/16 thick x 5" long x 1 1/2" wide.

[QUOTE=JJ Donohue] I just completed the prettiest BRW bridge I've ever made
[/QUOTE]
Pics, please?

There is another option. You could glue in a piece of wood into the slot and remake the slot to the proper width. If you have any left over wood this is pretty easy to do and if you match the grain a bit, you probably won't be able to see the patch.

Don't ask me how I know this......

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

I got one you can have just PM me your address. I'm not sure if it is tall enough but it is definently wide enough. Let me know.
blake (at)   dysonguitars.com

WOW...that was quick!!!

Thanks for the offer, Blake but I just got an offer from one of our bros who has thicker stock. He must have made similar errors so I don't want to reveal his identity

Either that or we're now onto something that enhances the guitar's performance...yeah, that's the ticket Hint: His last name begins with a letter in the last half of the alphabet. Thanks mucho, Mr. X!

Anyway, thanks for the quick response...this forum is the best!

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JJ
Napa, CA
http://www.DonohueGuitars.com

One more thing...

Sam...I don't have pics yet. The BRW blank came from the Zootman and it has multi-colored swirls and curls all over. It's just a simple modified belly bridge but once I sanded and polished it to 12,000 grit, I fell in love with the look.

This bridge is my first attempt at angling the saddle slot toward the south so that the string force is directed more toward the bottom of the saddle slot. I still have to figure out why a .125" spiral bit produced a wider slot Any clues?

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JJ
Napa, CA
http://www.DonohueGuitars.com

JJ,

Sounds like you are covered. If you find that you are still in need let me know and I will slice you a piece off some bone I have here........it will be unbleached though.

Shane

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Canada

Hi JJ,
Say Brother, I have several of those saddles.
High Quality Bone!!

If you need a couple extra saddles , let me know and I can drop them in the mail today!!
Let me know!

regards,
walterK

Does that mean the saddle is not cut at normal 90 degree angle? I believe that when you make multiple cuts you have to adjust for the fact that the bit is not at a 90 to the face of the bridge. Raising the bit not only deepens the slot but it also presents new face material to the cutter. Or so it seemed to me when I held a pencil up to the side of a piece of paper.

Hopefully the lousy drawing helps.


I was thinking of doing the same on my next bridge and without having to think about your post I would have made the same mistake.
BobK38973.6352777778

[QUOTE=JJ Donohue]I still have to figure out why a .125" spiral bit produced a wider slot Any clues? [/QUOTE] There are several reasons why it could happen-
1) Bearing play in your router/Dremel
2) Router/Dremel slide not firm - movement.
3) Saddle movement during cutting.
4) Cutting tool wandering.
5) Cutting tool over-sized.

I use a smaller bit and make the slot wider by opening up the travel in the tooling.

You should always expect a .125 tool to make a slot wider, unless you are using a milling machine.

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

my supplier has 1/4 wide saddle blanks as a stock item .. Iuse them for my multiscale and baritone guitars where i have a 3/16 saddle. Let me know if you ever need more JJ (or anyone else) and I can hook you up.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

J.J. I am guessing that you are using a older MultiPro Dremel. The bearings in them had a bout a 30 hr life That is exaggerating but the real issue was a combination of two problems. The bearings they used wore too fast at hi rpm and the journal (the area on the shaft that the bearing race pressed on to was not really a good interference fit and to boot the bearing housing was molded plastic that warped with heat. This make the sound like junk, but that is not true for there true intended function. But to use them as a precision cutting tool and expecting the run-out to be true enough for precision milling or circle cutting was for many a leap of faith that did not make it. The new 400XPR has a much better bearing and shaft set-up. I have been told but do not know that the 220v MultiPro are better than the older solid black 120v MultiPro. I don't even think they make the 120v Multipro any more.

Also if the collet is worn it is possible that the bit was not seated concentric to the shaft. This will also cause runout.

JJ PM me and I will send you some. I have some nice bone that are taller and thicker than normal. I know just sanded a few. Can compensate them how you want

I don't use a Dremel for this for the very reasons that many have cited. The slot was cut with a 1/8" spiral bit in a Porter Cable laminate trimmer using the John How designed jig. The bridge was elevated about 1/8-3/16" on one side and wedged in place (it didn't move). The .200" deep slot was made in 4 passes.

This same router-bit-jig combination produced exactly 1/8" cuts when routing a standard vertical cut in the past.

I think Bob K. may be on to something...I have to think about it a bit more, but if this is what happens then I will need a source for slightly wider bone blanks.

Tony, can you post your source or PM me...thanks.

Also...thanks to all who have so generously offered to send me a wider saddle blank...I should have one in my hands this weekend.

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JJ
Napa, CA
http://www.DonohueGuitars.com

[QUOTE=BobK] Does that mean the saddle is not cut at normal 90 degree angle? I believe that when you make multiple cuts you have to adjust for the fact that the bit is not at a 90 to the face of the bridge. Raising the bit not only deepens the slot but it also presents new face material to the cutter. Or so it seemed to me when I held a pencil up to the side of a piece of paper.
[/QUOTE]

Bob,
I think this is not the case. Won't the cutter be raised axially within the laminate trimmer, not merely moving vertically?

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

Steve,

I'm not sure I understand exactly what you mean but I think the answer is yes and that's exactly the problem - if you don't reposition the fence. I haven't actually tested this ( and I do have the flu right now so hallucinations are possible), but if you make an angle cut on a table saw then raise the blade but leave the fence alone wouldn't the kerf be wider?

btw- I really like your tag line.BobK38974.4122222222

JJ, I've got a source too if Tony's doesn't work out for you. Well, talk this weekend. P

btw, bring that bridge with you and maybe we can get to the bottom of the problem. Pwoolson38974.4158680556

Bob,
I hope this drawing clears up what I'm thinking on this.
The tool in a laminate trimmer would not move the same as a table saw blade.
The drawing on the left shows how a table saw blade would move, what I believe you are thinking.
The drawing on the right shows how the tool in a laminate trimmer would move, which would not cause the slot to be wider.

What am I missing?

(Please pardon the grammar in the drawing, and anywhere else that I write!)

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

Steve,

Aha, you are correct. My bad. Thanks for the 2 diagrams that cleared up my error.


Bob KBobK38974.5890625

If you raise or lower the bit in the laminate trimmer it should be fine. However, if you raise or lower the work piece, you will get the effect SteveS describes and your slots will be wider.

[QUOTE=JJ Donohue] .... The slot was cut with a 1/8" spiral bit in a Porter Cable laminate trimmer using the John How designed jig. The bridge was elevated about 1/8-3/16" on one side and wedged in place (it didn't move). The .200" deep slot was made in 4 passes.
QUOTE]

Wow JJ. Almost exact thing happened to me. During ASIA, I had borrowed Lance K's jig that John gave him. I made 3 bridges, one which I decided to use on my latest. I want an unbleached bone and nut set.

I'l have to read this thread thoroughly. Thanks for posting, I almost let this thread drop off the radar!Terry Stowell38974.9159606481