Hello,
I just finished a jewelry box for a christmas gift. The veneer was oiled and then I sprayed about 4 coats, wet sanded, another 4 coats, wet sanded again and gave it about 3 more coats and let it dry for several weeks with the intention of buffing it to a high gloss.
When I went to buff it the other day I was really shocked to find that there were cracks in the finish, not cracks like a plate of glass but more like what a river might look like on a map….is this due to too many or heavy coats?????????? pleeease help ,,,it has to be done for x-mas. how do I make the repair?
Thanks for the help
Bob
Replies
Cut your losses now, and remove the whole lot with a chemical stipper now. What sort of lacquer did you spray-if it was precat. then it sounds as though the oil was not dry-anyway precat is in theory not compatible with oil.
Then I would use Bulleye Zinsser dewaxed shellac in place of the oil, and then spray the lacquer.And it will still be finished in time for the lady for Christmas.
That's my sixpence worth.
Edited 12/21/2005 3:16 am by philip
My guess bobbycass, like Philip, is that you've applied a pre-catalysed lacquer, and from your description (if it was pre-cat) you certainly applied it much heavier than any manufacturer would recommend. Pre-cats, for the most part should have a dry film thickness between about 4 and 5 mils. This, in effect means two full coats of up to about 15 mils and, at a maximum, three is about your limit.
Thicker than this and the sheer thickness of the coat will almost certainly cause what's known in the trade as cracking or sometimes chinese writing if the cracking is bad enough. Typical (but not exclusively) cracking mostly runs across the grain, but chinese writing means the cross grain cracking is joined by many long grain cracks. The thickness of the coat causing problems means that the amount of shrinkage it experiences can't be contained within the film. Cracking doesn't usually show up in pre-cat until weeks or months after polish application.
Anyway, I could be barking up the wrong tree and you didn't use pre-cat, but again as Philip said it's not normally advisable to use pre-cat over oil finishes without using special techniques to overcome compatability problems such as using a shellac barrier coat or using a highly thinned out lacquer misting technique applying two or three coats prior to spraying a full coat or two.
It looks like a strip and re-polish job is your most likely route to rescue the job. Metheline chloride strippers are very effective for this kind of thing on non water based finishes. Slainte.
Richard Jones Furniture
You got carried away, Bobbycass! Way too much material! You have now experienced crazing. The only way to fix it is to strip and start over. For some reason, novices think that many coats of a finish is the way to get a glass like surface, but this is far from the truth. Now you know. It doesn't matter what the product is, too much will cause problems, now or later. Sorry, been there, done that.
PS. Lacquer and oil are not compatable. You should use a sealer with oil or use a natural sealing stain instead.
Beat it to fit / Paint it to match
Edited 12/21/2005 9:39 am ET by hammer1
Lacquer is a very hard, inflexible finish. Too thick a film will crack and craze. It's best to use not build up too many coats.
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