Hard Shellac Questions

[cpsmusic]

Hi Guys,

I'm resurrecting an old project (a ukulele) that had to get put on hold for a while.

I'd finished the uke with Hard Shellac according to the instructions, applying a series of coats to build what I thought was a fairly thick finish.

Today I planned to finish the surface with 800/1200 sandpaper and then polish with a buffing compound. However, I realised today that my finish quality was not very good - the surface was quite uneven. I'm pretty sure that the problem is that the uke is built from mahogany and I didn't use a grain filler. It looks like the uneven-ness is because of the unfilled grain. I tried sanding the back of the uke to a flat surface however it's basically taking all the finish off.

I built this uke mainly for the learning process so I'd like to give it the best finish possible and I'm not too fussed if that involves more work.

Just wondering what the best way to rectify my uneven hard shellac finish is?

Do I have to sand it all off, then fill the grain, then re-apply the hard shellac?

Is there a solvent for hard shellac that would take it off a bit quicker?

Any other suggestions?

Cheers,

Chris

[surfdabbler]

You can easily dissolve shellac in alcolhol (or metho). I recently did this with a bowl that I had covered in shellac. I had quite a thick covering, and decided that I didn't like the orange colour, so I dissolved it all back off, and used white shellac instead.

I've not done any grain-filling with shellac, but I believe you can use pumice and alcohol and rubbing to fill the grain without having to take off the shellac that you've already laid down. If you have a thick coating you might even just be able to rub the shellac into the grain with just alcohol, but I'm not sure on this.

[cpsmusic]

You can easily dissolve shellac in alcolhol (or metho). I recently did this with a bowl that I had covered in shellac. I had quite a thick covering, and decided that I didn't like the orange colour, so I dissolved it all back off, and used white shellac instead.

I've not done any grain-filling with shellac, but I believe you can use pumice and alcohol and rubbing to fill the grain without having to take off the shellac that you've already laid down. If you have a thick coating you might even just be able to rub the shellac into the grain with just alcohol, but I'm not sure on this.

I tried rubbing the finish with some 100% metho but it didn't seem to dissolve it at all. I suspect that whatever is in Hard Shellac that makes it "Hard" also affects whether alcohol dissolves it?

[surfdabbler]

Ah, I looked it up and you are right. Hard shellac has additive that makes it not dissolve in alcohol once it's cured. :( I suspect even pumice won't work then, as the shellac won't re-dissolve.

[chrisb691]

I did a box with hard shellac, and rubbed it back with 1000 grit wet & dry wet down with white spirits. Come up nicely.

[Elill]

I use this stuff for most of my work and have always followed Neil's instructions for it. In saying that, he has told me that white Shellac is better for things that migh get "dinged" as it is easier to fix/softer.

This last point I didn't know. I thought "hard shellac" must be best because its hardest - not so. My understanding is it is really designed for counter tops that might have issues with spilling and heat - this is what its good for. But I guess it is also brittle.

I called uBeaut before I finished a hall stand I just made. He said, do hard on the top and white shellac on the rest of it for the above reason.....now I didn't because I couldn't be bothered mixing up two batches....time will tell I guess.

Anyhow - instructions:

1. Sand to 400
2. wet down with hot water
3. Sand to 400 again
4. Apply sanding sealer/grain filler - I do a 20/80 shellac/metho (100%) sealer with a dash of talc (like a pinch)
5. Sand to 400 (this should now be super, super smooth)
6. Brush on 50/50 mix of shellac/metho with a camel hair mop
.
.
.
through the grades
7. Final sand and finish with eee ultrashine

This gives a nice even finish