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PostPosted: Thu Dec 28, 2017 4:50 pm 
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First name: Daniel
Last Name: Petrzelka
State: Washington
Country: United States
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Does this look like an original or replacement bridge plate on this 1977 Guild D35-NT?

I've got it on the bench due to some pickguard shrinking causing top cracks. Going to do the same as I do on Martins—carefully pull the pickguard and replace with a replica using sheet adhesive rather than gluing directly to the wood.

I don't have any specific need to touch the bridge plate, just don't know if they used these large rosewood plates in their '70s builds as they did in Nazareth, PA.

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PostPosted: Thu Dec 28, 2017 4:52 pm 
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Here are the cracks I'm repairing (nothing to do at all with the bridge plate I'm asking about)

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PostPosted: Thu Dec 28, 2017 11:32 pm 
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Old Growth Brazilian Rosewood
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Location: Ann Arbor, Michigan
First name: Hesh
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Hey Daniel this looks original to me. I've had a 77 in a few days ago and an 80 in today and both had over sized EIRW plates like your pictures.

I used to own a 1977 D-25 that I picked out for myself in 1977 when home on leave for the Holidays. I remember making the store go though all 10 of them that they had just received as I attempted to pick out the best one...;). Back then everyone immediately put Grovers, gold Grovers on these too and that's what I did too. Guild made a great guitar back in the 70's early 80's and some believe their 12's to be the best ever produced. Sorry that I'm digressing, just a fan of old Guilds here too....:)

Happy Holidays to you!

Oh yeah on these we put a patch in under the fret board extension and reaching to the sound hole and maybe 1/2" to each side of the fret board extension. It cleats the cracks in this area and greatly strengthens the extension area. There is a name for this patch but I'm forgetting but I've put dozens of them in. It's invisible if done well and if you want to call me at the shop on Tuesday I can walk you though it on the phone. Numbers on our site.

The other cracks are so very dirty in the pics that they likely have been open for a long time and any effort to force them closed will create stresses elsewhere on the top and consequently more cracks in time. I would be inclined to fill the ones that won't close all of the way or that you can force closed over several days of high RH but when permitted to reequalize at 45% RH open up again.



These users thanked the author Hesh for the post (total 2): dpetrzelka (Fri Dec 29, 2017 11:15 am) • Clinchriver (Fri Dec 29, 2017 6:44 am)
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PostPosted: Fri Dec 29, 2017 11:24 am 
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Thank you Hesh - I will definitely give you a call on Tuesday to get more info on the fretboard extension patch—thank you for the offer. With the bridge plate I only plan to do the requested slotting and replacement of the pins with unslotted Waverlys.

Regarding the dirty top crack. I've been fortunate enough to primarily deal with clean top cracks that I can close with humidity and light pressure. Cleaning with distilled water if needed and then gluing with HHG and light cleating on the back.

If this doesn't close well with humidification, do you recommending filling with a spruce strip and HHG, or do you ever use shellac sticks as Frank Ford outlines in a few of his blog posts?

I'm inclined to stick with spruce if needed.


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PostPosted: Fri Dec 29, 2017 12:16 pm 
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Don't know if that is original or not but I did have the heavy rosewood b/p replaced on a 1974 D-18 and a 1980 D12-28 along with some thru the sound hole scalloping and in my opinion both guitars improved dramatically. Also had pick guard cracks cleated and a new p/g put on the D-18. This was some time ago before I felt capable of doing the work (and the resets that were also done at that time)

I know its kind of controversial to do mods like that - my reasoning was that '70's Martins were never going to be valuable collectors guitars and everyone who has played it feels its a better player now. Not suggesting you do it to your Guild , just my experience.


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PostPosted: Fri Dec 29, 2017 12:19 pm 
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Old Growth Brazilian Rosewood
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Hi Daniel. Looking forward to speaking with you Monday, I typically leave in the early afternoon if there is not a lot to do and we are below zero here keeping business for now a bit down. As soon as it warms up we will be fixing cracks for months....;)

[imghttp://www.beeculture.com/wp-content/uploads/2015/05/1Berry.jpg[[/img]

Oxcilic acid or wood bleach can be used to bleach some of the dirt in the crack and at times it can really improve things dramatically with several applications. Might want to give it a try. I mix a bit in a disposable cup and work it in with an acid brush.

When I was apprenticing for Dave Collins 12 years ago step one in fixing cracks was to wash my hands. This was Dave talking not Felix Ungar here for a change. Reason being when we poke and prod around top cracks any dirt on our fingers can migrate into the crack.

In the past several years we've been viewing cracks (on instruments....) a bit differently. Sure we can force a lot of cracks closed with 75% RH over 3 to 5 days but our thinking these days is to also let the thing reach equilibrium again for several days at 45%. If the crack is no longer closed we know we are creating stresses by forcing it closed and then cleating it. Or, in other words the same guitar will be back next winter with a new crack on the other side....

And that's just not something that we want to be a part of since guitars are people too.

So our current thinking is if we can force it closed and it stays closed for several days at 45% we glue it shut, level, cleat it, bill the client, next. But if not we fill.

There is some new thinking, well it's not new but in the last ten years or so at Elderly instruments where when appropriate for the instrument.... colored to match ep*xy can be used as a filler with a BJR (back joint reinforcement with beveled sides) on the underside to keep the crack stable and the ep*xy from falling through when wet and just applied. We've done a bunch of these too on lower priced instruments or something that is not valuable such as your Guild and it works great. You have to get it right the first time though and clean-up can only be water while things are still wet.

Otherwise the ole method of adding matching material, leveling, touching up the finish, cleating as well, etc. is an option.

Anyway we can talk about it Tuesday, have a very Happy and safe New year!


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