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Dave Mcintire
12-20-2006, 7:51 AM
I have two questions for the chemists of whom I am sure there are a few out there on SMC.

1 Is there anyway to redissolve or thin Plastic Wood - the commercial wood filler that always seems to turn into a hard piece of colored concrete in the little can?

2 I have some pieces of solid carnuba wax that I would like to also dissolve and mix with varnish or shellac or something to make my own wax/finish. I can't find any petroleum type solvent that will dissolve this stuff but I know there must be some way to do it as its even used on pills and food as a coating.

Steve Schoene
12-20-2006, 9:17 AM
Acetone should work as a solvent for Plastic Wood, though DAP does sell solvent specifically for plastic wood.

Most petroleum solvents ought to dissolve carnauba wax, as will turpentine. But you need a bit of heat to speed this along being careful that the wax solvent is never placed on an is OPEN FIRE OR HOT BURNER. I'd use a hot water bath.

However, I question the benefit of mixing the wax with a top coat. It can be done--Tried and True has a commercial example--but why not just make your own paste wax with the lump. That's all paste wax is, a blend of waxes softened by being dissolved in a solvent. But mix in a little paraffin to make this possible to use or perhaps beeswax. I've not done this so can't provide any specifics.

Jim Becker
12-20-2006, 9:18 AM
The T&T product uses bee's wax which is far easier to disolve than hard carnuba.

Dan Larson
12-20-2006, 10:22 AM
Acetone should work as a solvent for Plastic Wood, though DAP does sell solvent specifically for plastic wood.

Most petroleum solvents ought to dissolve carnauba wax, as will turpentine. But you need a bit of heat to speed this along being careful that the wax solvent is never placed on an is OPEN FIRE OR HOT BURNER. I'd use a hot water bath.

However, I question the benefit of mixing the wax with a top coat. It can be done--Tried and True has a commercial example--but why not just make your own paste wax with the lump. That's all paste wax is, a blend of waxes softened by being dissolved in a solvent. But mix in a little paraffin to make this possible to use or perhaps beeswax. I've not done this so can't provide any specifics.
I agree with Steve. Also would like to reiterate his caution about heating solvents. It's remarkably easy to set yourself & your shop on fire while doing this! Best to just avoid doing it altogether in a non-lab environment. Rockler sells the "Sam Maloof Oil/Wax Finish", which I think is actually a mixture of oil/varnish/wax. Why not just buy a pre-made finish and save yourself the safety risk?

If you really want to dissolve beeswax or carnuba in solvent, toluene or xylene are the solvents of choice. A few ounces of wax per pint of toluene or xylene will dissolve at room temperature if you let it sit for a day or two, with occasional shaking.

Dan

Rich Engelhardt
12-21-2006, 7:53 AM
Hello Dave,
I'm not a chemist, but I have reconstituted plastic wood.
I had access to an almost limitless variety/supply of solvents back in the days I used to sell the stuff (70's).

We had to toss quite a few cans of Dap in the "dog" colors - like Red Mahogany - that didn't sell and had turned hard in the can.

MEK almost worked.
MIBK would work.

In layman's terms, think of MIBK as Acetone on crack/meth & steroids.
It's nasty stuff, and not worth the risk of having around the house/most shops.