Hello All, here's my dilemma. Swapped tuners on an '87 J-40. Changed out the big square gold Martin keys for a set of NOS '80's Nickel Grovers. All seemed fine til I looked at the front of the headstock today. Several (most) of the washers on the front side have small, semicircular bubbles around the outside edges (not quite halfway round the washer). Apparently I tightened the nuts a tad more than I should have, loosening the nitro from the downward force of the washer on the headstock, though at the time I had thought I was being pretty careful and had done quite a few of these swaps without this ever happening. I have some thin liquid nitro and was wondering if I should attempt to use a pipette to apply a drop at the inside of the bubble edge at the shaft hole and see if it would wick it's way underneath to fill the void and (hopefully) dissolve the surrounding lacquer enough to make the bubble disappear. I'm just guessing at this and have just a little experience using nitro for drop-filling dings, etc. Has anyone ever fixed this problem? Any help/guidance appreciated. Thanks.
I would try a little Acetone the same way.I did use Butyl Cellosolve at one time but I can't buy it anymore. it was grate stuff for this kind of repair.Also grate for fixing some finish checks.P.S if you are in the USA you will likely be able to buy Butyl C. Good luck with your repair.Bill...................
I have some Acetone, but I will check for the Butyl C--thanks for the heads up. Is it a bad idea to use nitro? I was thinking it would melt into the existing lacquer skin and it would kind of lay down and bond it to the rosewood. But I guess the solvents you mentioned would do the same thing and with a more measurable effect. Thanks much for the reply.
Are the blisters raised like bubbles? If they are only white marks from the lacquer separating they can be quickly taken care of with thin superglue. If they are actual raised bubbles a slow evaporating solvent will allow the finish to lay back down.
They are very slightly raised. I am afraid if I try cyano the whitish bubble will remain, even though the void will be filled. That's why my initial thought was to use nitro--hoping it would fill up the void and make the whole area nice and clear again. I'll try to post a picture soon to show what i am seeing. Thanks for the help.
I've repaired this malady in the past following these steps. I mount a fresh X-acto blade and slice into the lacquer bubble at it's most displaced portion. I lift the finish with the blade and wick in BC and let it sit till things look mushy. Then I ladle in lacquer that I've thinned maybe 15-20% to obtain good flow into and under the lacquer. It looks terrible but it allows the finish to re-adhere nicely. Once it's hard yaddah yaddah.
I've also lifted the lacquer from the rim of the hole out to the bubble without cutting. Sometimes it works by simply working an extremely thin blade under the finish. I fashioned a little right angle flat hook from some .020" stainless shim stock and sharpened the working end so as to facilitate slipping between the finish and the headstock. It doesn't always work, but when it does BC wicks right in without fooling around with lacquer.
BTW, I found another use for this shim stock (SS) that has proven quite handy at times. I use it to raise intransigent nuts from their beds. If I have a nut that won't come out easily, I trim a section of SS that's maybe .015 narrower than the nut and about 2.5" long. I sharpen one end of it as sharp and thin as I can get it. I work the sharp end gently under one end, usually by gripping it close to the sharp end with duckbill pliers. Once it's started under, even just barely, I move the pliers to about .125" away from the nut, get a good grip on the SS, and, using my fretting hammer tap the pliers such that the SS wedges under the nut. I continually move the pliers back as the SS advances. It will lift the nut to it's thickness (.020). If it still won't come out I leave the SS in place and slice the nut lengthwise right down to the SS. I use a Dremel with the most aggressive toothed slitting blade or an abrasive disc, whichever is handy. It parts the nut and doesn't touch the neck at all. I keep SS cut into small strips (with tin snips) in a section of drawer where I can easily choose the right size for the job. It takes all of 3-4 minutes to make up a small assortment that can be modified into a variety of little "helpers".
Thanks, all, for the replies. I've been looking for Butyl C and have drawn a blank--Googled and checked Stew-Mac. Can anyone point me in the right direction to purchase some?
I use Behlen's Jet Spray. It is marketed as a blush earser. The main ingredient is n-Butyl acetate which is probably very close to or the same active ingredient as used in butyl cellusolve. Butyl cellusolve sounds like a trade name that is a mix of the active ingredient and what it is used for. I simply spray a little jet spray into a cup and use a small pipette or dropper to apply it on the area I want to reflow. It will take several applications depending on the thickness of the finish. Stew Mac carries it.
Thanks, Mark--I'll check it out.
Ask Stu Mac they did handal it. Bill..............