Kevin, I'm experimenting with this too. I have some instruments that need some serious finish work in our collection without the budget for farming it out. I'm not in a hurry, but I want to move the skills along. So I'm building and trying to properly finish a piano bench using baltic birch. I'm discovering some ways NOT to proceed.
I started by applying a coat of Rust-oleum specialty lacquer (black) from Home Depot. I decided I would need to go through far too many cans of that, spraying and sanding down between, to get as smooth a finish as I wanted, given the baltic birch starting point. Then the comedy begins.
I tried putting down a layer of West System epoxy, leveling it off with a squeegee, but when it came time to sand a few days later, the sandpaper gummed up too quickly for the approach to seem practical
I tried putting down a layer of basic Bondo body filler, but maybe I mixed it wrong, because trying to sand it after the recommended curing time gummed up my sandpaper almost instantly. Besides, I didn't manage to apply a thin enough coat, so there was an awful lot of dust generated when I returned to it with my orbital sander a few days later using 80 grit, and by the time I was beginning to see things reasonable smooth, I was seeing some bare wood.
I ran to the auto supply store and grabbed some solvent based glazing and spot putty and applied a coat to the whole surface. It cracked badly as it dried, so I ended up sanding most of that off.
I flipped the sheet over and started fresh. I applied some Mohawk black grain filler, with no undercoat. I followed that with some of the Rust-oleum aerosol lacquer. I haven't sanded that yet but I'm interested to see what I get.
Three more products look interesting to me. Mohawk makes a black primer for wood (aerosol only), which might be a better starting point. I have an HVLP system, so a gallon of their colored lacquer (black, pre-thinned for spraying) might be a better choice than buying more aerosol lacquer. And they have a product actually called Piano Lacquer, also in the gallon, that allows more build than their Finisher's Choice Lacquer, which I bought for another project last year.
Good thing I'm only working with a rectangle of plywood thus far!
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Floyd Gadd
Regina SK
306-721-9699
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Original Message:
Sent: 04-20-2015 14:10
From: Kevin Fortenberry
Subject: Finish Touch Up/Rejuvenation - Black Lacquer
Very helpful- I have been thinking about coming up with something like this also.
One further question along this line:
I will be needing to apply some type of black lacquer or black paint to a music desk I am replacing on one of our older practice grands. Not terribly concerned about "matching" the current piano finish (what is left of it 😕) but just want something I can do myself like in my garage, etc--and than I can rub out with steel wool to at least look like a piano finish. This is plain raw wood so I need to prime really well also. I could easily just use spray paint to prime/fill in the wood grain but I'm concerned about compatibility--please advise. Kevin
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Kevin Fortenberry
Registered Piano Technician
Lubbock TX
806-778-3962
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