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View Full Version : any disasters from putting shellac over sticky linseed ?



JDarvall
23rd September 2011, 09:40 AM
you know how linseed can take forever to dry, and how if your not careful you can put too much down and it goes all fricken sticky.

What will happen in an attempt to fix, if you just coat it with a thin layer of shellac to seal it all up, so its all unsticky all of a sudden. What happens to the finish (long term ? )

tea lady
23rd September 2011, 09:45 PM
Rough guess is it won't work. The shellac has to have some timber to bind too. Ya can't just put the proverbial band aide over it all. :C

JDarvall
24th September 2011, 05:59 AM
ta. I just don't know.

I've heard that. but also I've read that it can be laid down immediately before shellac before its been given a chance to dry.

Also read that its a mistake because the oil will be oxygen starved which is needed to go off if covered in shellac.

I've done some tests on scrap and the finish looks fine. but thats only after a week.

wondering if someones done this years ago and the finish still no different.

jimbur
24th September 2011, 09:34 AM
I've never had it happen to me but the theory is that, in french polishing, if you don't spirit off the linseed oil (used in very small quantities as a lubricant for the rubber) you can get crazing of the surface down the track.
Cheers,
Jim

J.B.W
24th September 2011, 09:57 AM
I would rub some turps over the oil to thin it down and penetrate the timber. I would not put shellac over tacky oil. You can add a small amount of turps to shellac to give it more working time.

JDarvall
25th September 2011, 05:46 AM
thanks for your thoughts. ta.

Be interesting to see how that would occur. I'm going to coat some scrap next time I'm finishing with multiple coats of linseed then cover with shellac. date and stick it on the wall and see what happens.

Christos
25th September 2011, 12:10 PM
Was it the raw or boiled linseed oil.

I thought boiled has some solvents to allow it to dry quicker. So my question would be could you put a coat of boiled linseed oil over the top of raw linseed oil to help in drying?

Please understand that I never tried this and it is just a theory.

JDarvall
28th September 2011, 07:02 AM
thanks.