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I am getting ready to glue a classical bridge as specified in Cumpiano’s book. He positions it and scribes a line around the bridge with a razor blade. He then puts 3 layers of masking tape around and outside the line. I guess he does this so the bridge doesn’t move during gluing? I am thinking that the tape is not going to be enough to keep the bridge from moving all over the place during gluing.

Is there another method that I should explore?

Thanks,

Doug Ubele

P.S. - I am surprised that he doesn’t glue the bridge like he does his fingerboard. He drills though the unfretted 1st and 11th frets, positions it, and then nails some brads in just below the neck shaft. He then takes it apart, applies glue, places the brads back in position, taps them down a bit, and clamps it.

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Guitars...One's too many...Twenty is not enough.

I drill two holes in the saddle slot and use toothpicks to position it correctly. Once I have it in the correct spot, everything is square and not canted, and the proper amount of compensation, I use a pencil and trace the lower right corner, and the upper left corner of the bridge just so I know it is in correct place once glue and clamps are added.

Be careful not to drill through a fan brace.

Best wishes,
Joshua French

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Instagram: @jfrenchluthier
Web: https://www.jfrenchguitars.com/

I like that!

Thanks,

Doug Ubele

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Guitars...One's too many...Twenty is not enough.

I basically do the same thing as Joshua but I mske minature, Very slightly tapered, round dowels out of the same wood I make the bridge out of. When the glue is dry I cut them off and sand them flush.

I have holes in the clamping block so the dowels can go through the top and the clamp.

I also use the masking tape around the bridge before I glue so that when I apply the glue it doesn't go where it's not suppose to. It also gives me a line to butt the bridge against just in case there may be a tiny bit of play when I use the pin method.

my 2 cents worth...
The dowel and toothpick methods work well but for some reason I get a little nervous about drilling holes in my super thin classical guitar top, especially if there is no bridgeplate underneath and if it is cedar. I have found that Cumpiano's method of taping around the outline of the bridge works well if you put more tape around the bridge. Instead of three pieces put a half a dozen or more. Make a little trough around the bridge and it will stay put.
good Luck!

Robbie,

The guitars on your site look awesome, and I suspect they are a combination of your own design and a lot of experience. You mention your tops are very thin, I was curious how thin the top plate is on your guitars? I have built only Hauser style guitars and his tops are around 2.4 mm. I'm curious how thick other tops are. Any other classical players feel free to speak up.

Cheers!

John

John,

I take cedar down to around 2mm. I take spruce down to around 1.8mm   Of course this will all depend on the individual characteristics of each top. Some need to stay a little thicker and some can go a little thinner. This is regardless of whether I use a bridgeplate underneath or not. It also depends on what type of fan bracing I am using. If I am using a Fleta type system, for example I leave it thicker in the middle of the sound board bridge area and use a bridgeplate and then thin the perimeters to super thin. There are a lot of variables. I have also used different thickness on teble and bass sides of the top. One that worked well for me was 2.3mm on the bass side and 2.1 on the treble side. This was on a cedar top.
On classical guitars you need to think thin, but how thin is too thin?