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Hi Folks,

I see people doing it both ways - some glue the bridge on then finish the whole thing in one shot, and some scrape away the finish and glue the bridge on last.
What's the best way, and why? Can I mask the bridge area, then finish, then remove the masking, clean up and then glue the bridge on? Don't see why not.....

All input gratefully received, thanks! This is about all I have left to do on my first classical guitar.

Cheers,
Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

Dave,
I think you can do it both ways and some do it but I think masking it and doing it after may be the best way. For sure you'll have a fresh, clean gluing surface...

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

I always glue on the bridge first on classicals (I also do it on steel strings), this allows me to string it up and make any adjustments to plate edge thickness to get the string response that I'm after. French polishing or oil finishing is easy with the bridge in place.

What finish are you going to use? If you are going to French polish then trying to do that with the bridge position masked is asking for trouble as you will find it difficult to polish neatly up to the tape and risk leaching tape adhesive into the finish so to me that would not be an option. If you are spraying a finish then masking the bridge position on the top is no problem.

I think the division between gluing on first or afterwards is probably down to the builders history. This e that start out building classicals most likely glue on first, whilst those that started out building steel strings and diversified probably finish first then glue on the bridge. Though I stated out making steel strings and moved into classicals!

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Colin,

I'm dealing with exactly this issue right now. How do you work up to the bridge nice and close and keep the finish looking even? Its driving me crazy.

Applying a nice French Polished finish is something that I want to master, having a tutor available to show you "Like this..." would sure go a long way! My results so far are not bad, but not yet what they could be.

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

I made a little, small muneca that I could form into a point to get close to the bridge, and around the neck joint. One thing I did notice is that it doesn't seem to matter if you are polishing cross grain, if you are working it in and not laying it on too thick. If it goes on too thick, you can see the marks, if you keep it thin, and work it in, there aren't any marks. I do try to vary the strokes though, when I'm polishing. When glazing, and stiffing off, I go in both directions in the area of the bridge. Probably a no-no, but it seems to work for me.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Thanks for the advice guys. I won't be FP'ing this one. The customer wants a hard durable finish so I'll probably use Enduro pre-catalized eurathane. I'll mask off the bridge position, spray and rub out/polish, then fit the bridge later.

What should I put on the bridge? I think just a wipe over with fretboard oil maybe......?

Cheers,
Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

Me too, I am about to start varnishing(tru-oil) my first classical. I would appreciate your explanation on what technique you utilize near the bridge.

Thank you

Douglas, like Waddy says, use a smallish muneca and work very thin coats and stiff and glaze across the grain very thoroughly as well as with the grain. Don't worry too much if you get some on the bridge, you can't avoid it, a lot of classical builders do put finish on the bridge anyway, but it is easily removed with an exacto knife of scalpel after you have finished, just put some very low tack tape around the bridge to protect the top and gently scrape it off.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Good tips above. Although I glue my bridges after FP in almost all cases because of the much cleaner results that can be obtained.
On the rare occasion that I haven't, an approach that works is to very carefully mask off the bridge. That way you don't have to concern yourself with the application vis a vis the bridge, just the area around it. Once that is done, mask the top around the bridge and FP it separately.

Thank you Colin et all for the valuable tips.

Dave;
What I do is make a template of my bridge shape -only 2mm less in every demension.
Then I apply a thin coat of Shallac to the top.
Then I locate the exact position of the bridge and using doublesided tape I stick the template on.
The shellac helps it come off without tearing the wood.
Being 2mm smaller in every direction allows you to finish right up to the template and get a good smooth one .
Then after finishing the real bridge is fitted ; the finish under the back edge of it is scraped off very carefully to make sure there is a wood to wood glue joint.

Mike

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Mike Collins

Here is a tip that some might find useful. Use a q-tip and wrap a small piece of linen around it. Violá! You now have a small muñeca that can get into the tightest of places.

Just finished another flamenco. I sprayed a nitro finish on this one and did not put the bridge on until after finishing. For me, this was the right way to go. I found on an earlier build where I glued on the bridge prior to finishing, it was very hard to do a great job of level sanding around the bridge between coats.
After finishing was complete, I located the bridge, masked the area off with blue 3M painters tape, scribed a line inside of the mask (about 3mm) with a razor, and chiseled off the finish. The chiseling part only took about 15 min. I wanted the wet look on my bridge so I sprayed it with nitro prior to gluing. After I had the bridge glued and clamped, I carefully removed the blue tape. I did not wipe around the bridge top joint either, any excess LMI white glue that was present got sucked into the joint while curing. I don't like using an oil on a classical or flamenco bridge unless there is a bone inlay on the tie block, The strings will mess up the tie block. With a pore filled nitro sprayed block, the maple strips on my tie block are protected from the strings by finish.

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John Nowicki

I glue my bridge on before I attach the soundboard to the body.

Really David? Why? How do you position it accurately enough? I would have thought it's better to place the bridge after the body has all been closed up and the neck fitted etc. so you can position it very accurately.....

Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"