Should I sand this harp, and if so, how?

July 12, 2010 10:30 PM

I'd like to restore the original appearance of a 70 year old musical instrument that was spray-painted black some 40 years or so ago by the fellow that I bought it from. Is this something that can be accomplished with sandpaper and patience?

The instrument in question: a Deagan Vibraharp. Just the frame was painted over, and I'm only interested in restoring the cream and black outer trim with the logo, so the surfaces in question will be easy to get to with some disassemble.. I imagine some fine sandpaper combined with great patience and care could do the trick, no? If you've done this sort of thing before any advice on what type/grain of sandpaper to use would be great.

posted by waxboy to sports, hobbies, & recreation (9 answers total)

I would talk to a luthier who specializes in restoring old solid body electric guitars. It would be much the same process. I believe it is a combo of sandpaper and some stripping solution. Even if they cant get it original, they could probably put a new finish on that matches. Also cross post this to some woodworking/antique/luthiery boards. Let me know if you come up with anything eh? I've got a 59 ES-175 some clown painted...like with a brush, cherry red. Best of luck.
posted by timsteil at 11:22 PM on July 12, 2010

I think it will come off with just stripper unless he sanded down the metal before he painted, which I doubt he did. I would get some paint stripper and put a big glob on a small area to test it, leave it on a couple of hours and I bet the paint wipes right off. If you sand it, you'll scratch that nice finish under the paint. 3M make a non-toxic stripper that is pretty good, but of course, the toxic stuff works better and faster.
posted by lee at 11:54 PM on July 12, 2010 [1 favorite]

The trick is going to be removing the top layer of paint without damaging the original finish. I agree that sanding is not the way to go but I wouldn't just buy regular paint thinner yet. First I would try to find out what the original finish was made of and see how well the spray paint had adhered to it (scrape or scrub in an inconspicuous spot then proceed to testing solvents). Ideally you would then find a solvent that would remove the spray paint but not the original finish, which is possible if the spray paint is water based and the original paint was oil. I'd start by rubbing/ gently scrubbing with a very gentle solvent like Krud Kutter (from Lowes or Home Depot) which will remove most latex paint but not oil. If the spray paint seems to be oil based then try something like mineral spirits or a specialty restorer product to see if you can lift just the top layer before pulling out the big guns (commercial paint stripper formulas). If you do use paint stripper do a small area at a time and remove it as soon as the paint starts to soften up to minimize the damage to the under surface. Scrub gently to remove the parts that don't just peel off. If you leave it on too long you might end up with bare metal in spots.

Anyway's that's what I'd try. I have no idea of the value of this instrument but from my limited experiences restoring furniture I'd say the chances of local disaster on your first attempt are at least medium high so it might be worth taking it to a pro.
posted by fshgrl at 12:19 AM on July 13, 2010 [2 favorites]

Not sandpaper. Definitely start with mild chemicals tested in inconspicuous places, and ramp up slowly from there. Once you get the paint off you may need to do a little extra (and very gentle) touchup with a Scotch Brite pad soaked with more of the chemical that worked, but you don't want to use much pressure or you'll tear up the finish.

I also really agree with fshgrl's closing comment: "I'd say the chances of local disaster on your first attempt are at least medium high so it might be worth taking it to a pro."
posted by mosk at 1:55 AM on July 13, 2010

Hey Wax

Oddly enough, I was looking at the wikipedia bit vibraphones, and they have a pic of the old Deagan factory here in Chicago, where the instrument was invented. Says it is now home to a company called Century Mallet Instrument Service. I would bet they could point you in the right direction
posted by timsteil at 4:22 AM on July 13, 2010

It looks like the original finish on the frame could have been 'Frosted Duco' which would be a type of nitrocellulose lacquer, so I would certainly avoid anything like lacquer thinner. This was used a lot for cars of the era so maybe some googling of car restoration might help.
posted by Rhomboid at 5:24 AM on July 13, 2010

Don't use Scotch Brite on paint like that. Its abrasives aren't of a uniform size and you can easily dig through the unwanted finish into the wanted finish. If you need an abrasive, use steel wool.
posted by gjc at 7:10 AM on July 13, 2010

If the underlayer is lacquer I think you might be screwed. Lacquer comes off more easily than spray paint. Contact a pro!
posted by fshgrl at 10:54 AM on July 13, 2010

Preliminary analysis shows that the spray paint is on there good. There is some cracking and slight peeling, but this seems to originate in the original layer and light scrubbing in these areas reveals bare wood. It's also pretty dinged up throughout, especially corners, and wood is visible in more places that I originally noticed :( I'll experiment with mild to moderate solvents and report back.
posted by waxboy at 12:13 PM on July 14, 2010