I've been a fledgling luthier for awhile now, and only do it a few hours a day and mostly on inexpensive instruments. It's a break from playing really, and gets my second love of tinkering satisfied. I refer to Frank Ford's frets.com for info frequently. I've gone to Frank once in the past for info, but now he refers those with repair questions to this site.
Just got my first broken headstock on a Epiphone acoustic. I got the glue up done alright, but infortunetly the owner didn't save the missing pieces. So now I need to improvise. I haven't done the "is it lacquer or is poly test?" but since it's a newer guitar from Asia I'm assuming it's poly. By the way, I have filled poly finishes in the past with tinted super glue, but as you might know it leaves that "drop of oil in a bucket of water" opaque look. Not that it really matters on this guitar, but that I'd get some more experience.
Here's the front of the headstock with missing chunks of finish and wood. I thought I'd try epoxy this time with Behlen burnt umber tinted to get the color close then scrape, sand, and buff. Then I thought I would paint in the darker grain where it would be missing. I know, but I have to try it for the experience. Thoughts from anyone? Finish to put over the top of the painted grain?
Now here's a photo of the back of the neck. Yeah, it's a huge hole and I'm really not sure about this one. Unless someone says something differant, my thoughts are; cut a rectangular hole using a knife (what kind & where?) dremel or saw. Leaving a slight inward taper on the cut. Then take a mohagany dowel and and mirror the taper, cut a groove for the truss rod to move, leave it proud and again...scrape, sand and buff ??? What kind of finish can I put over the bare wood that would work well with the poly? Anyone?
I know this seems like a lot of work for this guitar, but I'd hate to try it on a more expensive guitar for the first time. And, the kid that owns it probably wouldn't buy another guitar. There's not a lot of discussion about matching poly finishes including frets.com, and maybe for good reason. Except for the UV dentist tool and that's not going to happen for me.
Just want to get it as close as I can, thanks ahead for any help anyone can offer...
Would a french polish work over poly?
*see the finish repair portion of Frank's article. He goes over repairing a poly finish.
Maybe I'm the only one here, but with the missing wood on the back of the neck, I would never have accepted this repair into my shop. Sorry to sound harsh my friend, and it's probably just me.
It is quite easy to sand the front veneer off the headstock, and that is what I would be doing. Find a nice thick- (er) veneer to glue on, trim it off and put a few coats of Tru Oil on the front. Make sure when you are sanding the veneer off, that you have callipers handy and keep doing measurements all around the edge. You have to know if you are taking too much off in any one place.
Remember, the veneer on the front is actually structural, and in certain circumstances, will prevent the headstock from breaking off. Don't bother just filling the holes, do the job up right! Good luck with this, and please post pictures when it is finished OK?
Au contraire, Mr. Krishna. I believe the headstock fix is straight bread-and-butter... the hole on the back of the neck is an gilt-edged invitation!
Mack's instincts regarding beveling a mahogany patch are spot-on. There's lots of satisfaction to be had there. Not only would the repair be accepted here, it would be welcome with open arms... my friend.