Best method of reattaching a acoustic pickguard.

musicalstash

Any ideas of the best what to reattach a slightly warped scratch plate back on the an old Yamaha acoustic  ?

The pickguard has come off quite clean  , but the problem is that it is quite thick and warped in places ( plus a few small cracks ) which only only makes contact to the body around its edges  .

Have looked online for a similar replacement guard with the hummingbird being the closest but I think it will be too small

Any advice would be appreciated.

https://imgur.com/a/592GoVB

ICBM

I've used epoxy - high-strength Araldite - for this. It may sound like overkill, but actually the force needed to keep a warped guard tightly down is huge, and many other glues will creep over time and the guard will come loose again. Superglue would also probably work but there's no way to avoid damaging the finish around the guard, since it would be impossible to not get any squeeze-out if you've used enough to guarantee a full bond.

To clamp it on you will need to make a caul the same shape as the guard but slightly smaller - something like 3/4" MDF will be ideal - and a large one for the inside, to spread the load evenly over the braces. A single big G-clamp will be enough. You will inevitably get a lot of squeeze-out but it's easy enough to wipe off, with enough kitchen roll - you've got a couple of hours before it starts to go tacky. If you miss any it can be scraped off cleanly once it's gone rubbery but not fully hard.

musicalstash

Thanks for the quick response and the indepth answer.  Will attempt it on the weekend only concern is the guard is quite fragile / brittle with some small cracks and forcing it down may snap it. 

Is this the stuff I need 

https://www.screwfix.com/p/araldite-2-part-epoxy-adhesive-tubes-opaque-2-x-15ml/2457h?_requestid=742562

ICBM

musicalstash said:

Is this the stuff I need 

https://www.screwfix.com/p/araldite-2-part-epoxy-adhesive-tubes-opaque-2-x-15ml/2457h?_requestid=742562

No, that’s the Rapid which isn’t really any good. It’s the standard high-strength, slow-set type you need.

https://www.cooksongold.com/Stringing/Araldite-Standard-2x15ml-Tubes-----Un3082-prcode-998-340?p=gs&gclid=EAIaIQobChMI0pvUlJyQ5QIVB7LtCh2euwH7EAQYCSABEgKUV_D_BwE

If you’re worried about it cracking, try a test flattening of it onto a table or something. I’ve not done a Yamaha one so I don’t know for sure if it’s the same as the plastic Gibson used.

musicalstash

Just collected some clamps from.a friend to attach the pickguard but he said as the pickguard looks to be  celluloid it could continue to shrink causing the top of the to crack .  

There's a couple of stew Mac videos mentioning it where he probably got his information from but I think this would take decades rather than months     

phil_b

musicalstash said:

Just collected some clamps from.a friend to attach the pickguard but he said as the pickguard looks to be  celluloid it could continue to shrink causing the top of the to crack .  

There's a couple of stew Mac videos mentioning it where he probably got his information from but I think this would take decades rather than months     

Im no expert but please do not use araldite for this. Because if the guard ever has to come off ie if it shrinks more you will not be able to remove the epoxy glue without damaging the wood

It may be better to replace the guard with a new plastic one so it is not warped and wont shrink

phil_b

a quick look on youtube 3m transfer tape seems to do the job

ICBM

phil_b said:

Im no expert but please do not use araldite for this. Because if the guard ever has to come off ie if it shrinks more you will not be able to remove the epoxy glue without damaging the wood

Yes you can. You take it off with a sharp scraper.

phil_b

ICBM said:

 

Yes you can. You take it off with a sharp scraper.

not really. even if you do this it is likely it will also pull of the finish or a thin layer of the wood it is stuck to.

but I guess it does depend on the value of the guitar. Like I said I am no expert but I have been watching a lot of luthier repair videos and the all seem to advise on not using epoxy. tape seems to be their preferred method for pickguards. They also never try and reuse a warped pickguard

ICBM

phil_b said:

not really. even if you do this it is likely it will also pull of the finish or a thin layer of the wood it is stuck to.

but I guess it does depend on the value of the guitar. Like I said I am no expert but I have been watching a lot of luthier repair videos and the all seem to advise on not using epoxy. tape seems to be their preferred method for pickguards. They also never try and reuse a warped pickguard

Have you actually done one?

I have successfully done so with several. With something like an old Gibson it’s either that or use a replacement guard, which is considered a devaluation.

Slash'N'burn

How did you get on with this?
I was searching for advice on adhesive to refit my old acoustic pickguard, found this thread and noticed I have exactly the same 70’s Yamaha FG300 as you!

Mine has warped badly so that the pointy edges lift away, I think it’s celluloid.  It has been badly reglued many times before. Scraping the old glues off, it is bare wood underneath.
Im also going to try and straighten the pickguard to get it flat, as it still has some flexibility in it, so may try hot water to soften it then clamp it under some heavy books for a while.

What is the best adhesive to use? I can’t use tape as the pickguard is semi transparent.

ICBM

I think you’ll be lucky to get it flat enough to reglue like that. The force produced as they shrink is enormous.

If you can’t replace it, I would use high-strength epoxy - eg Araldite, slow set type. It’s not only very strong, it has the advantage of very long working time so you’ll be able to spread it very evenly and thinly over the guard so it will form a complete and invisible layer.

You’ll need to make a clamping caul the same shape as the guard and slightly smaller to give enough room to clean up squeeze-out, and a block on the inside to fit between the bracing - you’re going to need a lot of clamping force, eg with a large G clamp or two.

(Just realised I repeated myself rather here! But the same advice still applies - I have successfully done this with epoxy, but not with any other method.)

musicalstash

Slash'N'burn said:

How did you get on with this?
I was searching for advice on adhesive to refit my old acoustic pickguard, found this thread and noticed I have exactly the same 70’s Yamaha FG300 as you!

Mine has warped badly so that the pointy edges lift away, I think it’s celluloid.  It has been badly reglued many times before. Scraping the old glues off, it is bare wood underneath.
Im also going to try and straighten the pickguard to get it flat, as it still has some flexibility in it, so may try hot water to soften it then clamp it under some heavy books for a while.

What is the best adhesive to use? I can’t use tape as the pickguard is semi transparent.

I ended up just having a replacement made, tried to reattach using double sided 3m tape but it just would no sit flush and lifted on the edges (plus it has shrunk) .  Was tempted to use araldite but decide against it as the guard was cracked in places.