French Pollish Advise

[BioPirate]

I am in the process of fixing up an old table. I sanded it back to the bare wood and applied a french polish. One section of the polish appears to be lifting as though paint stripper is on the wood. The table is quite old (about 200 years old) and has been through floods and many years of abuse with crap being spilled on it and treated like crap.
Should I rub it back to bare timber and start again? Or dose someone think whatever it is has soaked into the wood?

[Honorary Bloke]

I sanded it back to the bare wood and applied a french polish. One section of the polish appears to be lifting as though paint stripper is on the wood.

Can you explain the process you used a bit? French Polish is something you DO, not something you APPLY. What finish did you use on the wood?

[BioPirate]

The stuff I used was a product I got from Bunnings. It is called Mastertouch French Polish made by Feast Watson. It has the consistency of a watery estapol and is brown in colour. The instructions on the bottle say to sand existing varnish to a mat finnish and for raw wood to have it finely sanded. Application is then by brush or lint free cloth allowing about one hour between coats. The product can be thinned with metho. The finnish on the rest of the table is acceptable to my skill level appart from this one patch. I have never used french polish on anything so I assumed the stuff I had was french polish. From experiance what is on the lable isnt always the truth.

[Honorary Bloke]

OK. This is something coming up from the wood. It is not paint stripper, since you didn't use any, so it is likely trapped moisture (water), tree sap (if it is that kind of wood), or oil (if it is THAT kind of wood.

As a first step I would sand back the bad patch, wipe with methos (to remove any oil or sap), let dry and re-coat. See if it does it again. If not, Bob's your uncle, if so, it might be moisture and I would sand back and let it dry a while.

I don't know that product,so can't comment. I would have used a shellac (sanding) sealer first (and you may want to) to seal in the "stuff" that is rising.

[ian]

Bio

it's unusual for shellac (which is what French polish is) to lift off

my initial questions / thoughts are:

how many coats have you applied?
how did you apply the polish?

was the table a uniform colour after you sanded it back?

how fine was the grit you were using when you finished sanding?

did you finish sanding by hand with the grain ?

did you wash the table top with metho or warm soapy water after sanding?

you may want to scan the data here http://www.feastwatson.com.au/WaxesFrenchPolish.asp



ian

[andrewsd]

Did you do any anti-silicon preparation before you applied the shellac? If the table has ever had a "Mr Sheen" type product on it, the polish won't take.

[BioPirate]

how many coats have you applied?

Three

how did you apply the polish?

Spray gun to get an even finish. The top was the last surface to be done

was the table a uniform colour after you sanded it back?

The table has been through too many floods and treated too bad over the last 35 years to be able to get any even colour. There are stains all over it. My sight isnt overly good but it did look as even as it was going to get

how fine was the grit you were using when you finished sanding?

800

did you finish sanding by hand with the grain ?

yes

did you wash the table top with metho or warm soapy water after sanding?

no

you may want to scan the data here http://www.feastwatson.com.au/WaxesFrenchPolish.asp

ian

Chears
Baz

[BioPirate]

Did you do any anti-silicon preparation before you applied the shellac? If the table has ever had a "Mr Sheen" type product on it, the polish won't take.

I didnt do anything other than sanding. Over the last 200 years it probably has had all sorts of stuff put on it

[andrewsd]

Sanding won't remove silicon, unless you really take off a lot of material. The stuff is impossible to remove unless you hit it with a solvent. Wipe it down with Prepsolv on a clean rag. Use a different piece of the rag every time you wipe it or you will just move the silicon around.

Good luck.

[andrewsd]

You will need to take it back to the wood again before you prepsolv it.

[ian]

Baz
I'm guessing that you may be dealing with melted candle wax or tallow or silicone contamination

a lesser cause might be a "smallish" problem with the surface exacerbated by an old batch of shellac.



ian