PDA

View Full Version : Sanding Shellac + talc grain filler















mingus
22nd September 2007, 05:21 PM
I am experiemnting with using a shellac and talc mix as grain filler as discussed in neil's book and am having trouble sanding, the finish just rolls up and clogs the paper.

I have mixed 1tsp talc with 100ml hardened shellac and left to dry for about a week before sanding with 400 grit. I have tried a few other grade of paper (higher and lower) with the same effect. Another test i did with plain hardened shellac sanded beautifully, so i guess it had had enought time to cure.

Is there anything i can do to make sanding easier?

ubeaut
23rd September 2007, 01:24 AM
Don't use hard shellac. Almost any other shellac is fine so long as it's petty fresh. You may also need to thin the shellac prior to using it with the talc. Most of the ubeaut shellacs need to be thinned at least 50/50 with good metho.

You should probably also check the use by date on your hards shellac.

Cheers - Neil :U

mingus
23rd September 2007, 10:42 AM
Interesting, so the additives which make hard shellac harder prevent it from curing properly when you add talc? No wonder i never understood chemistry :U

The date is fine, i only bought it a couple of weeks ago. Can you sugest another clear grain filler i could use? I probably wont have a use for another bottle of shellac for a while.

ubeaut
23rd September 2007, 11:27 AM
What timber? Can you use a neutral grain filler or one to match the colour of the timber.

Other alternative is sanding sealer. Not ours, but one of those thick syrupy ones like Wattyl.


You could try a really watered down hard shellac talc mix. Like 5-6 parts meths to 1 part shellac. Just use s few ml of shellac for a trial and a tiny bit of talc. Try it on scrap first allow at least a few hrs to dry even better over night.

What is the use by date on the shellac?

mingus
23rd September 2007, 12:15 PM
The usd by date is sept 2009, so no probs there.

The timber is vic ash, so there is a lot of grain filling to be done. Thanks for the info.