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Making a Bridge Setter - good idea or not?

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Forum topic by paulmon posted 01-13-2021 02:55 PM 344 views 0 times favorited 9 replies Add to Favorites Watch
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paulmon

141 posts in 1107 days


01-13-2021 02:55 PM

Topic tags/keywords: jig question

I don’t know how many people make or have made musical instruments here, but I thought I’d post this anyway because it’s kind of an interesting (?) jig.

I’ve been working on a ‘contraption’ to allow setting the bridge fore and aft, up and down, and side to side. The idea is that once the bridge is properly located, it can be marked and then glued down to the top. For this first prototype test I am using a cigar box uke that I’m making. Hopefully if this works out, the jig will be a little more universal in usage.

So here’s my question for you all. Is there something like this already? Is it even necessary? Should I continue on with this project or should I just give up. Bridges have been set since forever, but I will say that after tinkering with setting the various parameters, I felt like it was like, really really in tune.

https://youtu.be/pYoZE4ZUE94


9 replies so far

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SMP

3190 posts in 878 days


#1 posted 01-13-2021 04:30 PM

Most people just use deep clamps, sometimes called bridge clamps from places like Stumac.com, they also sell a bridge caul that applies even pressure over the bridge. Personally I just made some cam clamps from Paul Sellers video, i just made them extra deep. Since they are wood they don’t mar surfaces, and i can superglue wedges to fit between bracing etc. No need to reinvent the wheel imo.
https://m.youtube.com/watch?v=JSO5QFQhQk8

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Loren

10934 posts in 4620 days


#2 posted 01-13-2021 05:00 PM

I’ve not seen a bridge positioning jig. Stewart McDonald’s would sure sell one if one were available though.

What I do is put the bridge in position and carefully tape around it so I know exactly where the glue is going to be. I also scrape the finish off that area and prefinish the bridge. It’s a hassle but results are fine.

I’m sure big factories must have some method of reliably positioning bridges, probably some sort of overhead arrangement that holds the body of the instrument and clamps the bridge from above. Some luthiers use a vacuum clamp though that does not guarantee positioning it does avoid the problem of the bridge swimming when the clamps are tightened.

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Foghorn

922 posts in 359 days


#3 posted 01-13-2021 05:25 PM

Pretty cool jig Paul. Stew Macs sells the intonator which is used to set the location of the saddle slot prior to routing it in place on the instrument. I use the saddlematic from them to get very close for saddle position and the acoustic bridge bolts to temporarily attach the bridge so saddle position and intonation can be set. I then take the bridge off and rout the saddle slot with a simple jig. This allows you to make sure the bridge is square to the instrument center line. The only potential issue I can see with your prototype is that the slot and saddle are already in place. You may get the intonation perfect but the bridge could be skewed as a result of the preset saddle. Having said that, you could still set intonation using your jig and a floating, temporary saddle and then rout the slot after you have confirmed intonation.

-- Darrel

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Craftsman on the lake

3638 posts in 4410 days


#4 posted 01-13-2021 05:37 PM

The standard way of doing this is to drill two small holes in each end of the saddle slot and through the top and put some pins or screws in the holes to be removed after the bridge is glued. Then glue the bridge on with deep clamps from the sound hole. You can put a gluing caul temporarily inside under the bridge if needed. Secure it there temporarily with double sided tape.

-- The smell of wood, coffee in the cup, the wife let's me do my thing, the lake is peaceful.

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paulmon

141 posts in 1107 days


#5 posted 01-14-2021 12:45 AM

I thought of exactly that and what I found out so far is that the issue of having a skewed bridge on a soprano uke is not much of a concern. It certainly will be as the intruments get larger – guitars for instance. I certainly am impressed by how in tune this uke is now, but I am beginning to come up with another version of this jig. And I will address this issue in that new design. Thanks.


Pretty cool jig Paul. Stew Macs sells the intonator which is used to set the location of the saddle slot prior to routing it in place on the instrument. I use the saddlematic from them to get very close for saddle position and the acoustic bridge bolts to temporarily attach the bridge so saddle position and intonation can be set. I then take the bridge off and rout the saddle slot with a simple jig. This allows you to make sure the bridge is square to the instrument center line. The only potential issue I can see with your prototype is that the slot and saddle are already in place. You may get the intonation perfect but the bridge could be skewed as a result of the preset saddle. Having said that, you could still set intonation using your jig and a floating, temporary saddle and then rout the slot after you have confirmed intonation.

- Foghorn


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paulmon

141 posts in 1107 days


#6 posted 01-14-2021 12:48 AM

Right. I am working on a version 2 of this jig and will try and incorporate something like that into it. I would like to make bridges where the saddle slot is routed into the middle part of the bridge instead of going all the way through. Thanks.


The standard way of doing this is to drill two small holes in each end of the saddle slot and through the top and put some pins or screws in the holes to be removed after the bridge is glued. Then glue the bridge on with deep clamps from the sound hole. You can put a gluing caul temporarily inside under the bridge if needed. Secure it there temporarily with double sided tape.

- Craftsman on the lake


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Craftsman on the lake

3638 posts in 4410 days


#7 posted 01-14-2021 12:59 AM



Right. I am working on a version 2 of this jig and will try and incorporate something like that into it. I would like to make bridges where the saddle slot is routed into the middle part of the bridge instead of going all the way through. Thanks.

The standard way of doing this is to drill two small holes in each end of the saddle slot and through the top and put some pins or screws in the holes to be removed after the bridge is glued. Then glue the bridge on with deep clamps from the sound hole. You can put a gluing caul temporarily inside under the bridge if needed. Secure it there temporarily with double sided tape.

- Craftsman on the lake

- paulmon

Yes, I just take a small piece of plywood, put the saddle on it, and surround it by 1/4” thick pieces. I have a palm router that slides over the top with guides to make the correct angle and stop it at each end. My saddles often change so I make a new one each time. Just made with scraps. I have a video about attaching the bridge here.

-- The smell of wood, coffee in the cup, the wife let's me do my thing, the lake is peaceful.

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paulmon

141 posts in 1107 days


#8 posted 01-14-2021 05:49 AM


Yes, I just take a small piece of plywood, put the saddle on it, and surround it by 1/4” thick pieces. I have a palm router that slides over the top with guides to make the correct angle and stop it at each end. My saddles often change so I make a new one each time. Just made with scraps. I have a video about attaching the bridge here.

- Craftsman on the lake

Nice looking guitar. I saw that you had 666 subscribers and I didn’t want continued risk to yourself so I became 667 to get you off of that number.
Your welcome :)

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Craftsman on the lake

3638 posts in 4410 days


#9 posted 01-14-2021 01:09 PM


Yes, I just take a small piece of plywood, put the saddle on it, and surround it by 1/4” thick pieces. I have a palm router that slides over the top with guides to make the correct angle and stop it at each end. My saddles often change so I make a new one each time. Just made with scraps. I have a video about attaching the bridge here.

- Craftsman on the lake

Nice looking guitar. I saw that you had 666 subscribers and I didn t want continued risk to yourself so I became 667 to get you off of that number.
Your welcome :)

- paulmon

Ha! that’s okay. My email begins with “[email protected]——.net”. I’ve had the same email address since 1984. I get lots of comments about it. Didn’t think anything of it as it’s a dimension hopping computer in a scifi book written by Robert Heinlein. Good book. Over the years I’ve been told things like I’m going to hell because of my email address.

The world is sometimes a strange place. Anyway, thanks for the subscribe….

-- The smell of wood, coffee in the cup, the wife let's me do my thing, the lake is peaceful.

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