Repairing Steam Blush to Lacquer Finish
Advice on fixing blush in a lacquer finish caused by someone using the tabletop as an ironing board. December 11, 2012
Question
I have a job refinishing an Ethan Allen cherry (stained) dining table. Problem area is a plate-sized blush spot. Customer indicated someone used the table as an ironing board. Seems to be under the lacquer. What is the best way to deal with this? Do I need to strip off the finish with 5f5, or sand and spray retarder, thinner, and new lac? I'd like to avoid messing with stripping and affecting the stain if possible.
Forum Responses
(Finishing Forum)
From contributor L:
If it is shellac, spray it with denatured alcohol and just wait it out. If it is lacquer, spray retarder and wait it out. If it is pre/post cat or poly, you will likely have to strip the top.
From the original questioner:
Thanks. Quite sure it is lacquer. I will try the retarder. Should that be straight, or cut with thinner?
From contributor L:
Either should work, as long as it is open enough for the water to come out of the finish. I would go with retarder. Let it sit and flash and whatever you do, don't touch it. Let it go as long as you can before you get the urge to touch it.
From contributor J:
Try a heat gun in a dry room first. Warm it up, excite the molecules, see if the water leaves the way it got in. Not so much as to curdle the lacquer. Then try the retarder. Just on the area, start light, get wetter as you get more desperate. Don't get your hopes too high. What looks like moisture blush can also be oxidized/cooked lacquer. Sometimes solvent resolves it. Good idea to clean the surface before doing anything - get as much Pledge off first - before opening the surface with solvent. You'll be wanting to over-finish and will be in the fish-eye zone.
From the original questioner:
Thanks. That sounds like good advice as well. I'll try the heat first. I did the wash down the other day. Hot soapy dish washing liquid, worked with very fine steel wool, then rinsed. I thought I'd let it sit and dry over the weekend. Been looking at some fish eyes this morning. Striped bass in Nantucket sound!
From contributor A:
I did this to fix the same problem on my brother's table and I read about it here on WOODWEB. Take some methyl hydrate (dna) and wipe over the spot with the blushing. Set on fire and let the flames burn out. The white spot should now be gone and your customers sufficiently freaked out ;)
From contributor I:
Where do buy methel hydrate (dna)?
From contributor L:
Denatured alcohol (DNA). I don't think he was referring to Deoxyribonucleic acid.
From contributor R:
It (methyl hydrate) is not denatured alcohol! It is methanol, MeOH. DNA is EtOH. They are not the same. CH3-CH2-OH vs. CH3-OH.
From contributor L:
Well, DNA is commonly known as denatured alcohol when you are talking finishing. What's the DNA stand for then?
From contributor R:
Contributor L, what in the world are you talking about? DNA in some circles is denatured alcohol. Denatured alcohol is ethanol denatured with something toxic to make it un-potable. Methyl hydrate is a very uncommon reference to methyl alcohol, or methanol. They are not the same.
From contributor C:
"Den-alcohol" is probably a better term for denatured alcohol. SD1-1 is the most common industrial grade and uses methanol (methylated - still is used in England and other European countries) as the denaturant. I believe it's 4 gallons of meth and 1/8th gallon of isopropyl to 100 gallons of ethanol, give or take. Methanol can be purchased through SW industrial sales or ordered through your local store. SD is also available from them.
From the original questioner:
This morning I sprayed some retarder on the table, and it cleared up the problem. I think my next step will be sand, spray care seal, then topcoats. Thanks for the advice!