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Anyone have a tutorial for making a classical bridge? Particularly interested in jigs for shaping the convex ends.

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A higher purpose for wood.
Rich Smith
Issaquah, WA

There's a jig for that?

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Waddy, looked through all 427 of your slides, but didn't see jig that you mentioned for shaping the wings on the bridge. Very informative slide show nontheless.

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A higher purpose for wood.
Rich Smith
Issaquah, WA

For most of us, it's called a rasp. And I guess I make liberal use of one of my Sorby paring chisels too, to square up the edges between the wing and the tie block and saddle "holder" (??)

I have a bridge blank shaped block that has the saw cuts that define the tie block edges and the saddle slot. I use this to set up the table saw and make the same cuts on the real bridge, then bandsaw the wings to rough thickness, then it's all hand work after that.

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Jim Kirby
kirby@udel.edu

Ditto on Jim's procedure. Grinding a "safe edge" on your rasp will help define the point at which the wings meet the center portion.
I also use a very small curved gouge and rat tail file to define the "lip" at the back.
I am however going to try to drill the string holes (I'm using the 18 hole design) prior the cutting the slot which defines the front of the tie block in order to eliminate tear out.

I added a method for classical bridge construction in the tutorial section of the forum.

I don't have any jig. I marked a piece of tape and cut the slots on a radial arm saw, then did the rest by hand.

Dave, your idea sounds smart. I did leave my block a little fat on the inside, then sanded it back severely after drilling. What helped the most, was drilling very slowly, and taking small bites, then cleaning the bit after each bite. I really ended up not getting much tear out. It took forever to drill 18 holes though, with each one having about 4 or 5 dips, with a bit clean after each dip.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Ricardo,

Here is a little tip for shaping the ends. Use you chsiel sharpening jig to clamp the bridge in. Set the angle you want on the tip of the bridge wings and then sand away on some sand paper just like you were sharpening a chisel. I start at about 150 and go to 600 grit.

I would hesitate to call this a tutorial, but it roughly describes (with some gaps) the way I build a classical bridge. Pictures are gathered from several bridges I have made on different guitars, but you get the idea.

--Determine the height
--Rough dimension some blanks
--Slot according to a dummy pattern bridge


--Bring the blanks to the right thickness
--Sometimes glue in the bone pieces at this point
--Curve the back with sandpaper dome


--Shape with rasp, chisels, files
--Drill


--Drill peg holes, make pegs
--Position on the guitar

Thanks for all the tips guys. What about drilling the holes? Should they be on an angle? I plan on one hole for each string and tying off in the classical style.

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A higher purpose for wood.
Rich Smith
Issaquah, WA

If you are going to use a standard tie, you want to make sure the hole is as deep in the slot between the saddle and the tie block as you can get it. If it is too high, the loop under the string will pull it up too much and you won't have a good break angle at the saddle. Depending on how you make your bridge, the hole could be angled slightly down from back of tie block to the inside of the tie block. to get it deep enough.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

You can also lower it with a trough between the tie block and the saddle ramp.

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Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

I made a jig for shaping the wings using a tavble saw. Here are some pics.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Here's a close up of the part that receives the bridge blank.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Here is the same part with a blank in it.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Ricardo, I also use a six hole bridge. If you click on the third picture down in my last post for a larger view, you'll see I'm drilling at an angle, I don't recall the exact angle but it is somewhere around 10 degrees from vertical. You need to calculate the entrance carefully so the hole will exit at the bottom of the slot--like Waddy said, so you get a good break angle.

Here the jig is placed on the table saw. This is just to show you I've placed some alignment blocks that fit my table saw. This way I don't have to align the jig manually everytime I use it.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Here is the jig correctly in place. Although clamps are missing in the picture to secure the thing down. Pretty important...

Notice the small blocker ring on the right. The position of this little guy defines the lenght of the wings on the bridge.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Raising the blade step by step, I do multiple passes, to limit chip out.
Here the first wing is done.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Then I flip the bridge and do the second wing.

That's what it looks like when out of the jig.

You need to put masking tape on the sides of the bridge blank (which i didn't do in this photo shoot) to avoid tearouts, such as you can see on the upper right corner of the tie block.

That's pretty much it. You will need to final sand the wings sionce teh dado blades leave a less than smooth surface.

It was pointed out on a different forum where I also showed this that a router table might do a better job than a table saw. I tend to agree with that, although not having a router table, I can't try it.

Good luck!

EDIT: Once the wings are roughted out using the jig, I slot the bridge in a similar manner than Marc showed, using a table saw. The reste is done by rasps, sand papers and scraper.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Thanks David for the tip on the safe edge on the rasp and the shaping of the lip, Gary for the tutorial and Robbie for the sharpening jig tip. Made my OLF day!

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Jim Kirby
kirby@udel.edu

Sorry Alain, I accidentally submitted a post in the middle of your sequence.

No pb Marc!

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

I start to feel some envy towards these power saws and the jigs. The few bridges I made so far were all made with a saw, a chisel, a rasp..the bare minimum. It takes a lot of time and I errored badly a few times.

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Build log

Hi Marc,

This is a little late, but I thought you might like to see my wing cutting jig. It is quite similar to Alain's, except that it uses a router instead of a table saw. Let me know if you have questions.

Regards,
Max

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Max Bishop
Brighton, Michigan