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trjohnson
03-13-2013, 05:11 AM
I am about to start a Stewmac soprano kit build, but would like to replace the bridge with a vintage Martin style. I can take the dimensions off of my '30's Style 0, but I'm looking for tips on how best to manufacture the bridge. I have very few power tools (a drill, plunge cut circular saw, and jigsaw), but I have a lot of hand tools for fine woodworking, including a variety of saws (western and Japanese), handplanes, and the Bridge City HP-6v2 multiplane, Jointmaker Pro, and drill guide.

Here is my current plan:

1. Lay out a long series of bridges along the edge of a surfaced 3/4" thick mahogany plank.

2. Use the HP-6 with a dado profile or else my plow plane to create the slot for the bridge. I can do 1/8" wide dados with either, so if that is too wide I will need to use a backsaw instead, or else take several passes with my jointmaker pro after cutting the bridges apart.

3. Drill holes for the strings.

4. Use the jointmaker pro to cut slots for the strings. The kerf may be too thin, so I might have to start with the jointmaker and then widen with my dovetail saw.

5. Use a rip saw to separate the bridges from the "mother" board and then to cut to approximate thickness--cutting through the holes drilled above.

6. Handplane and sand to size and shape.

7. Use the Jointmaker Pro to separate the bridges.

Todd

Beau Hannam Ukuleles
03-13-2013, 05:55 AM
The best way I have found is to buy a Martin uke, then carefully sand to dust everything but the bridge, then use that bridge. It's a real time saver

David Newton
03-13-2013, 06:28 AM
Beau is such a snark.

Why are you making a whole bunch of them?
You should get a piece of wood and use the tools you have and cut one out.

trjohnson
03-13-2013, 06:47 AM
Beau is such a snark.

Why are you making a whole bunch of them?
You should get a piece of wood and use the tools you have and cut one out.

Many of the milling operations are easier with longer and wider pieces. Hand plowing the groove would be difficult, if not impossible, if I cut the bridge to size first. Also, tool set up is often the most time consuming part of the job, so if I can make a few at the same time it will save me time later.

Todd

Nicko
03-13-2013, 07:14 AM
And you can open up a chain of "Martin Bridges 'R' Us" stores!

ksquine
03-13-2013, 07:32 AM
Sounds like it will make a Martin style bridge for you. 1/8" for the saddle slot is a bit wide. I'd go 3/32 but not a big deal. The string slots have to fit the strings (obviously) so check your saw kerf vs the string gauge

David Newton
03-13-2013, 09:39 AM
Also, tool set up is often the most time consuming part of the job, so if I can make a few at the same time it will save me time later.
I didn't realize you were going into production, I thought you were doing one kit.


The string slots have to fit the strings (obviously) so check your saw kerf vs the string gauge

+1 on this!

trjohnson
03-13-2013, 10:42 AM
I didn't realize you were going into production, I thought you were doing one kit.



+1 on this!

I wouldn't call it production exactly, but I would like to experiment with a few kits. Good way to decompress after pushing electrons all day.

ukegirl13
03-13-2013, 11:01 AM
Many of the milling operations are easier with longer and wider pieces. Hand plowing the groove would be difficult, if not impossible, if I cut the bridge to size first. Also, tool set up is often the most time consuming part of the job, so if I can make a few at the same time it will save me time later.

Todd

No, not impossible! But yes, easier with longer pieces.

Timbuck
03-13-2013, 11:06 AM
http://i219.photobucket.com/albums/cc143/shiregreenbod/PICT8669.jpg

trjohnson
03-13-2013, 11:19 AM
http://i219.photobucket.com/albums/cc143/shiregreenbod/PICT8669.jpg

Very nice. Are you using a router to round the edges? Do you cut the string slots before rounding? I typically do roundovers with a very sharp skewed handplane, but that might not work well if I cut the slots first. I'll have to experiment.

Pete Howlett
03-13-2013, 12:57 PM
I think you are old enough to work it out aren't you? Ken couldn't have given you more information if he tried!

Moore Bettah Ukuleles
03-13-2013, 01:09 PM
I always advise beginners NOT to build multiples. You'll only end up with a bunch of ukes with the same mistakes. It doesn't really speed up the learning curve unless you've completed a single uke and studied it's virtues. Start slow, learn well. It shouldn't be about making more ukes but making better ones. Good luck.

trjohnson
03-13-2013, 03:34 PM
I think you are old enough to work it out aren't you? Ken couldn't have given you more information if he tried!

Yes, the photo is quite helpful. But one thing I've learned from working wood is that little details in technique can make a huge difference in ease and results.

Timbuck
03-14-2013, 01:50 AM
I ran out of bridges and had to make some more.. So I took the camera into the workshop and tried to record the manufacture from start to finish..There's a lot of work involved and I put the pic's together in a slideshow..If anything is not to clear I can put more pic's on...It can be seen here..
http://s219.photobucket.com/albums/cc143/shiregreenbod/?action=view&current=c769c9d9.pbw
and here http://www.ukuleleunderground.com/forum/showthread.php?38067-Getting-in-the-groove&highlight=saddle+slots

And strange as it may sound...I gave the latest batch away .... Just because the saddle slot was 3/32" wide when it should have been 1/16" wide. :(

trjohnson
03-14-2013, 04:46 AM
I ran out of bridges and had to make some more.. So I took the camera into the workshop and tried to record the manufacture from start to finish..There's a lot of work involved and I put the pic's together in a slideshow..If anything is not to clear I can put more pic's on...It can be seen here..
http://s219.photobucket.com/albums/cc143/shiregreenbod/?action=view&current=c769c9d9.pbw
and here http://www.ukuleleunderground.com/forum/showthread.php?38067-Getting-in-the-groove&highlight=saddle+slots

And strange as it may sound...I gave the latest batch away .... Just because the saddle slot was 3/32" wide when it should have been 1/16" wide. :(

Thanks Ken. That's very helpful and certainly validates my impression that this is a complex task. My first attempt at making a bridge last night failed. I cut the blank to exact size with a Japanese saw, cut the slots with the Jointmaker, but when I tried to drill the bottom of the slots the bit tore the bridge apart as soon as it touched it. I even tried a sacrificial wood piece and it still mangled the bridge. Tonight I'll try a different approach along the lines you demonstrated, but adapted to my tools.

ChaosToo
03-14-2013, 04:57 AM
Is it just me, or is it not a lot of effort for 'hobby builders' to build very small numbers of such things when they can be bought 'in the rough' for pennies?

trjohnson
03-14-2013, 06:11 AM
Is it just me, or is it not a lot of effort for 'hobby builders' to build very small numbers of such things when they can be bought 'in the rough' for pennies?

Part of the woodworking hobby for me is in the learning and the doing. Sure I could buy a bridge, but it looked like a fun challenge to make one instead. And in the process I'm learning new techniques that can help when I need a part that I can't buy.

mzuch
03-14-2013, 07:12 AM
Is it just me, or is it not a lot of effort for 'hobby builders' to build very small numbers of such things when they can be bought 'in the rough' for pennies?

The same could be said about lutherie as a hobby in general. If I were to amortize the money I've spent on tools and materials over the number of instruments I've made, I probably could have bought as many K-brand ukes for less. None of us hobbyists is in this to make or save money.

ChaosToo
03-14-2013, 12:31 PM
Hey guys - not criticising at all. I love to mess about and learn new skills too. I'm currently revamping my first Uke, and that includes adding a new bridge, but the cost of making one would far exceed the cost of buying one. I can more than see the point if you're making plenty if them, but not for one or two

IMHO, of course :D

trjohnson
03-14-2013, 06:59 PM
I had better luck tonight, but learned that I need a few more tools and still more mods to technique to really do this well. I started by laying out two bridges on a 5" wide piece of mahogany that I crosscut to the right bridge width:

50301

Next I cut the saddle slots and did the main roundover. The roundover was easy to do using my old Stanley No. 4 plane and a bit of sandpaper. The 1/16" saddle slot was painful. I layed them out using a marking gauge and used the knife wall method to saw both walls. I then wrapped sandpaper around a scraper card to clean out the slot. I'm still not convinced that is level throughout. None of my hand routers or plow plane blades go as small as 1/16" and inlay tools are narrower than 1/16".

50302

I drilled the holes using my electric drill, then used by dovetail saw to separate the bridges. Finally, I cut the string slots using the Jointmaker, widened the two middle slots using my dovetail saw, then carefully planed and sanded everything to straight and true. The last operation was using an Auriou rasp to put a slight roundover on the ends of the bridge. It looks good from above, but because I hand drilled the holes they are slightly off:

5030350304

I'm not sure I'll use it because of the skewed holes, but it would probably work and look better than the stock Stewmac kit bridge. I'd just need to make an ebony bridge to complete it.

While using my 30's Martin for measurements I noticed some interesting details. First, the middle two slots on the bridge are clearly wider than the outer two and it looks like it was made this way rather than worn over time. Second, I don't think Martin drilled the holes in the same manner because the top of each hole is not round, but angled up toward the slot. It almost looks like they used a router bit that routed the hole and string at the same time. Finally, it looks like the bridge sits in a sliding dovetail--the saddle slot walls and saddle are slightly angled out from top to bottom.

Timbuck
03-14-2013, 10:33 PM
Martin used to glue the saddles in the slot.

Timbuck
04-02-2013, 09:57 AM
I'm making a fresh batch at the moment....Re "Cutting the bridge string slots"...I usually do this operation on the bandsaw with an indexing device..but the blade had worn out...I have not been able to locate another thin blade to do the Job...so I made I made a simple jig out of a chunk of 1/2" Corian that I had and did it by hand.....It works so well that i think i'll use this method in the future instead of the bandsaw...See here
http://www.youtube.com/watch?v=ILFYhjd3Q7I

Pondoro
04-02-2013, 10:40 AM
Making several bridges at once on the edge of a plank, as you suggested, lets you use power tools and keep your fingers far from the blades. I made 9 at once this way when I only needed one. I've used a couple more since. So I approve of your initial plan. There is no obligation to use them all.

http://i176.photobucket.com/albums/w163/pondoro_bucket/NinebridgesSmall.jpg

Pondoro
04-02-2013, 11:15 AM
Hey guys - not criticising at all. I love to mess about and learn new skills too. I'm currently revamping my first Uke, and that includes adding a new bridge, but the cost of making one would far exceed the cost of buying one. I can more than see the point if you're making plenty if them, but not for one or two

IMHO, of course :D

You make them because it is fun!

Rick Turner
04-02-2013, 11:34 AM
Ummm, errr...

A Martin style uke bridge should be one of the easiest things in the world to make if you have and know how to use woodworking tools, and there are a number of ways to skin this particular cat. If you have a table saw (oh, horrors!), a small band saw (or a hand saw, or a jig saw), a drill press, and a router table...yes, with a router in it...a Martin style bridge should take no more than about twenty minutes to make. In multiples, you're looking at between seven and ten minutes...sanded and sealed. Another five minutes for the saddle. Boom, kada boom, zip, zing, done.

What is the problem?

It's all about knowing the sequence and the tools you have to do the job. And if you don't have the tools, you probably shouldn't be struggling to build ukes unless you have well trained beavers and termites at your disposal.

Hint...make the blanks & round 'em over before you cut the saddle slot. That way you won't blow out grain into the slot in the round-over process. Make a jig to hold the blocks when you run 'em through the table saw to do the slot.

I don't know where this idea that table saws don't belong in a luthier's shop came from...They're so good, fast, and accurate at preparing square and rectangular stock...But then again, I spent several years as a cabinet maker, and that colors my whole approach. How do you even build shelving and work benches without a decent table saw?

Pondoro
04-02-2013, 03:14 PM
The largest reason that I could never become Amish is the fact that I couldn't use my table saw...