StewMac tools

fixing a poly finish ?

If you have a string instrument of any kind that needs fixing, a mistake you made in building a new instrument that you need to "disappear," or a question about the ethics of altering an older instrument, ask here. Please note that it will be much easier for us to help you decide on the best repair method if you post some pictures of the problem.

fixing a poly finish ?

Postby glen rudolph » Sun Jun 11, 2017 8:07 pm

Hi folks,

I have a guitar with a good size crack in the finish.It's a little hard to describe but the finish has actually curled up and
you can feel the ridge very easily where it is "cracked".The finish is a quilted sunburst with a clear poly on top.I'm not
expecting to do a flawless repair but I would like to do the best I can with it.It was like this when I received it so I could
not say what happened to it.Looks like maybe something was spilled on it or perhaps exposed to heat.Hoping the
photo will make it a little easier to see.Would appreciate any info you could tell me.I have seen a lot of articles where
the poly finish was filled with crazy glue and sanded down but I need to find a way to make the poly finish lay flat again
so this situation is a little unique I guess (it looks like if you saw a map and there was a mountain range,best I can
describe it,I would say the ridge is about 3 mm high).
Attachments
IMG_1039.JPG
pic 1.JPG
glen rudolph
 
Posts: 3
Joined: Fri Jan 22, 2016 6:43 pm

Re: fixing a poly finish ?

Postby Barry Daniels » Sun Jun 11, 2017 8:37 pm

Can you press the raised portion down with a tool, like a dull knife? If so, it might be reattached by holding it down while placing CA into the crack. Keep holding it down while you spray some accelerator on the glue. It may be necessary to hold the chip down for several minutes so find a comfortable position.

The glue can both fill and re-attach loose pieces of finish. Additional applications of CA will be necessary to fill the crack. Let it cure for a couple of days then scrape level, sand and buff.
MIMF Staff
Barry Daniels
 
Posts: 1729
Joined: Thu Jan 05, 2012 10:58 am
Location: Houston, Texas

Re: fixing a poly finish ?

Postby Mario Proulx » Mon Jun 12, 2017 12:58 am

Before you try anything, give us more photos. Different angles, different lighting. Hold a straight edge to it to show how much it is puckered.

At any rate, never hit CA with accelerator when doing a repair. Yes, it may work, but it may turn white. Depends on humidity and other factors, but CA is fast enough on its own. Put away the accelerator for this task....
Mario Proulx
 
Posts: 766
Joined: Fri Jan 06, 2012 12:08 pm

Re: fixing a poly finish ?

Postby Barry Daniels » Mon Jun 12, 2017 9:03 am

Some of the old liquid accelerators did create a white crust. I have not found that to be the case with the aerosol accelerator from Stew Mac.
MIMF Staff
Barry Daniels
 
Posts: 1729
Joined: Thu Jan 05, 2012 10:58 am
Location: Houston, Texas

Re: fixing a poly finish ?

Postby Mark Wybierala » Wed Sep 27, 2017 10:41 am

The older style clear flexible plastic packages that all new guitar string sets used to come in do not bond to CA. I used these when I need to re-secure lifting poly with a light clamp.
Mark Wybierala
 
Posts: 227
Joined: Fri Feb 03, 2012 10:14 am
Location: Central New Jersey


Return to String Instrument Repair: Practical and Political Issues

Who is online

Users browsing this forum: No registered users and 2 guests

Your purchase from these sites helps support the MIMForum, but only if you start at the links below!!!
Amazon music     Amazon books     Amazon tools     Rockler tools     Office Depot    

The MIMF is a member-supported forum, please consider supporting us with a donation, thanks!
 • Book store • Tool store • Links •