painting over tar?
 

Any suggestions on painting over tar?

It's old thin tar or bitumen on wood. In places it's soaked into the
wood and dried out. Elsewhere there's been repairs with more recent
tar more generously applied. I've scraped it down to wood but it's
still tacky. When I rest my weight on my palm while working here it
comes away with some tar residue which have to use solvent to clean
off.

Is there a hardener or sealant I should use or can I paint right over
tar? I don't think I want to use oil paint as the tar would likely
bleed through. But water based latex paint should not mix with the
tar.

Thanks for any adivce.

painting over tar?
 

On Nov 13, 1:53 pm, Wm Watt wrote:
Any suggestions on painting over tar?

It's old thin tar or bitumen on wood. In places it's soaked into the
wood and dried out. Elsewhere there's been repairs with more recent
tar more generously applied. I've scraped it down to wood but it's
still tacky. When I rest my weight on my palm while working here it
comes away with some tar residue which have to use solvent to clean
off.

Is there a hardener or sealant I should use or can I paint right over
tar? I don't think I want to use oil paint as the tar would likely
bleed through. But water based latex paint should not mix with the
tar.

Thanks for any adivce.

I would let it become part of the tar and use oil based primer, and
then paint as usual. Treat it as if it was wood, just my opinion. I
had a car once that had chickenwire cardboard, and tar for a fender;)

painting over tar?
 

On Tue, 13 Nov 2007 10:53:10 -0800, Wm Watt
wrote:

Any suggestions on painting over tar?

It's old thin tar or bitumen on wood. In places it's soaked into the
wood and dried out. Elsewhere there's been repairs with more recent
tar more generously applied. I've scraped it down to wood but it's
still tacky. When I rest my weight on my palm while working here it
comes away with some tar residue which have to use solvent to clean
off.

Is there a hardener or sealant I should use or can I paint right over
tar? I don't think I want to use oil paint as the tar would likely
bleed through. But water based latex paint should not mix with the
tar.

Thanks for any adivce.

This is a problem as much for woods that exude pitch or resin, as with
those where pitch was applied later.
Here's one approach: - with the wood really hot
(maybe blowtorched with care? )
scrape the ooze.
Then sandpaper.the surface.
Then scrub with alcohol etc.
Wait and repeat.

Brian Whatcott Altus OK

painting over tar?
 

On Nov 13, 12:53 pm, Wm Watt wrote:
Any suggestions on painting over tar?

It's old thin tar or bitumen on wood. In places it's soaked into the
wood and dried out. Elsewhere there's been repairs with more recent
tar more generously applied. I've scraped it down to wood but it's
still tacky. When I rest my weight on my palm while working here it
comes away with some tar residue which have to use solvent to clean
off.

Is there a hardener or sealant I should use or can I paint right over
tar? I don't think I want to use oil paint as the tar would likely
bleed through. But water based latex paint should not mix with the
tar.

Thanks for any adivce.

Well, I bought an old motorhome that had some leaks in it so I painted
it first with a tar like mixture that I got from the RV shop, then I
immediately followed with a silver "rattle can" spray paint job. The
paint lasted as long on the tat as it did in other areas. I dont
think you have to do anything unless its the texture of the surface
you are worried about.

painting over tar?
 

Thanks for all the feedback. I brushed and rolled a gallon of oil-
based alkyloid(?) paint on it, four coats, and it dried hard. Looks
good.