A better way?

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DarwinStrings
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A better way?

Post by DarwinStrings » Fri Oct 04, 2013 12:44 pm

Last night I scribed a bridge to a top and then scraped out the top finish to glue the bridge. Every time I do this I wonder if there is a better way. Maybe I am just a bit slow at it but it does take me quite some time cause I have to be so careful not to slip and then have to repair the finish. This time while I was scraping I considered masking off the area and using paint stripper to soften the finish before scraping to speed things up (might be showing my desperation there :) ). I don't want to try that on a guitar in case it stuffs the glue joint so I may spray up some test panels and try it on that first but before I go to the trouble, has anyone ever come up with a faster method with suitable results?

Jim
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kiwigeo
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Re: A better way?

Post by kiwigeo » Fri Oct 04, 2013 12:58 pm

I think youll find paint stripper will leave a goey gunge which youll end up having to scrape off to end up with a clean gluing surface.

I mask off all except the out periphery of the bridge area..that way I just have to do a bit of scraping..doesnt take me more than half an hour to get the job done. I wear a pair of magnifying binocular glasses and make sure Ive got both hands guiding the scalpelt/violin knife when I get close to the bridge line.
Martin

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DarwinStrings
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Re: A better way?

Post by DarwinStrings » Fri Oct 04, 2013 1:11 pm

1/2 an hour beats me Martin, I am about three times that. I suppose masking off would make me less scared and speed it up a bit.

Jim
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DarwinStrings
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Re: A better way?

Post by DarwinStrings » Fri Oct 04, 2013 1:17 pm

Oh and you use a violin knife, the one with a handle that looks like a skew chisel? That may be better as I just use a broken stanley knife blade. It wrecks my fingers too, can't play guitar after I scraped the finish.

Jim
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Re: A better way?

Post by GregL » Fri Oct 04, 2013 1:23 pm

Hi Jim,

I think Kathy Matsushita uses paint stripper when removing finish for the bridge. Maybe you could check her website?

Thanks,
GregL.

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DarwinStrings
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Re: A better way?

Post by DarwinStrings » Fri Oct 04, 2013 1:50 pm

Cheers Greg, I found it on her site. Kathy refers to the stripper she uses as "orange safe" so I checked that and found there is citris strippers available, sounds like it will save me a not so fun job.

Jim
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Re: A better way?

Post by auscab » Fri Oct 04, 2013 2:25 pm

Hi Jim ,
Do you glue down your bridges with HHG ? I'm thinking if it would be possible to scribe your bridge position before any finish is put down ,then brush coat within the scribe line with thick HHG, let it dry , finish the top.
Then put bridge back on and re scribe the line to just cut through the finish , after that either scrape through finish to the glue and dissolve the glue back with warm water or warm up the glue with a hair dryer and see if it and the finish moves . I suppose it could be done with other water soluble glues as well

To me , with scraping the finish under the bridge position I have always thought of the danger of damaging finish out side the line and also of creating a less than perfect joining surface, if I was to scrape at any of the sanded top timber.

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DarwinStrings
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Re: A better way?

Post by DarwinStrings » Fri Oct 04, 2013 2:52 pm

G'day and thanks Rob, I use yellow glue for the bridge and am happy to stick with that. I don't have any trouble with scraping the joint well, once I get through the finish, it is just the getting through the finish that I find time consuming and wearing on my fingers. Still your ideas sound sound enough.

Jim
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Allen
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Re: A better way?

Post by Allen » Fri Oct 04, 2013 5:28 pm

Some use a laminate trimmer with cutter just scoring through the lacquer and cleaning it up that way. I tried it once, but my bum was puckered up too tight for me to continue on with that method.

Others I've heard heat up a knife and use it to scrape up the finish. Not tried it, but I think it was Chuck Moore among others that uses this method.

Me, I've masked off the surface, and then sprayed and buffed. Then pulled tape off. Now I just finish the whole instrument and scrape it back. I mask the entire outside perimiter of the bridge area with tape to give me a bit of confidence in hooking in with a scraper. Takes me about 10 and no more than 15 minutes on my rather complicated footprint on my bridges.
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kiwigeo
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Re: A better way?

Post by kiwigeo » Fri Oct 04, 2013 6:43 pm

Allen wrote: I tried it once, but my bum was puckered up too tight for me to continue on with that method.
:lmao :lmao :lmao :lmao :lmao :lmao :lmao :lmao :lmao
:bum
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Re: A better way?

Post by kiwigeo » Fri Oct 04, 2013 6:45 pm

DarwinStrings wrote:Oh and you use a violin knife, the one with a handle that looks like a skew chisel? That may be better as I just use a broken stanley knife blade. It wrecks my fingers too, can't play guitar after I scraped the finish.

Jim
That's the one.....Ive got a set of the things and I keep them razor sharp. Theyre good for "hogging out" finish and when I get close to the bridge perimeter I sometimes switch to a scalpel with a stiff blade.
Martin

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Trevor Gore
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Re: A better way?

Post by Trevor Gore » Fri Oct 04, 2013 7:40 pm

Scribe around, really sharp dog-legged chisel used across the grain, ~15 minutes all up. (Figs 20-23 to 20-25).

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Re: A better way?

Post by vandenboom » Fri Oct 04, 2013 9:38 pm

I use the riskier technique Allen refers to using a dremel mounted in the small dremel base, then finish off with stanley knife blade. I do the same in the head block area before gluing fingerboard extension down. Depth testing obviously crucial and dremel has a tendency to walk as the bit is barely touching the surface - so, yeah, all a bit risky but no disasters yet and pretty quick. Frank

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Re: A better way?

Post by DarwinStrings » Fri Oct 04, 2013 10:41 pm

Thanks all, that made me chuckle too Allen. I should open that white book of yours more often Trevor. I think I am probably just being too ginger with it and sounds like I need to man up get rid of the stanley blade and scrape a little harder or yep buy one of those dogs leg jobs. I had read about that method Frank, thought I might go too slow and burn the thing.

Jim
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Re: A better way?

Post by ozziebluesman » Sat Oct 05, 2013 6:47 am

Can't add much Jim I mask off the area under the bridge footrpint mark with a pencil around the outline then use a violin makers knife in a home made handle (one of my first ever projects) and scribe about 2 mm inside the pencil line. Peel away excess and scrape and sand away. I use a French Polish finish and HHG on the bridge glue up.

Cheers

Alan
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Craig
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Re: A better way?

Post by Craig » Sat Oct 05, 2013 7:11 am

It takes me too long as well Jim . Have a try at turning the sharp edge on a smooth bit of hardened steel creating a hook on whatever your using to scrape off the finish.
Don't put masking tape on a recently French polished finish !! or you'll end up very pissed off ? :D
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Re: A better way?

Post by DarwinStrings » Sat Oct 05, 2013 12:08 pm

Cheers Alan, Craig. Comforting to know I may not be the slowest kid on the block Craig. Time to improve/change the method so I am looking forward to that bit on the next guitar now.

Jim
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Re: A better way?

Post by ozwood » Mon Oct 07, 2013 3:05 pm

Hi Gents,

Maybe I am missing something or about embarrass my self , But I just put a layer of tape down accross where the bridge is going to sit, position the bridge , score around it with a sharp exacto knife , remove the waste masking tape , spray , level sand and polish to my hearts content and then score around the edge of the tape,remove it and glue my bridge on,........... never a problem, and I know I'm not the only one who does it that way, if there is an obvious down side to doing it , it's not obvious to me !

Just my two bobs worths.

Cheers,
Paul .

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Allen
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Re: A better way?

Post by Allen » Mon Oct 07, 2013 5:38 pm

Nope..........That'll never work............. :lol:
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ozwood
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Re: A better way?

Post by ozwood » Mon Oct 07, 2013 5:54 pm

Nope..........That'll never work............. :lol:
Too simple you thinks Allen, not in keeping with complex and sacred traditions of Lutherie........aww shit :( :( :( :( :( , I'm not gonna be cast out am I.... :cry: :cry: :cry: .
Paul .

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Allen
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Re: A better way?

Post by Allen » Mon Oct 07, 2013 6:01 pm

One small step from being banned! :lol:
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DarwinStrings
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Re: A better way?

Post by DarwinStrings » Mon Oct 07, 2013 8:43 pm

I have to agree, far too easy Paul, keep your ideas to yourself next time.

Jim

Someone ban him so I can use it without him knowing please.
Life is good when you are amongst the wood.
Jim Schofield

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Craig
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Re: A better way?

Post by Craig » Mon Oct 07, 2013 8:55 pm

Sorry Paul ,,,,,,,,,,You're out
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charangohabsburg
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Re: A better way?

Post by charangohabsburg » Tue Oct 08, 2013 3:49 am

Wow, the last secret in luthierie has surfaced. :shock:

From now on luthiers will be just normal people like plumbers, professors and pedestrians are. :(
Markus

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It's only the others who suffer.

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Re: A better way?

Post by lauburu » Tue Oct 08, 2013 5:50 am

+1 for Ozwood
Guess I'll have to ban myself as well
Miguel

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