previous coat is still emitting vapors. These cause, first, bubbles, then pinholes when the bubbles burst.
SAGS
Spraying too heavily causes sags and runs. You may be spared the vision of an entire finish softening
and sliding off the wood because you sprayed too many coats too soon, and they softened and sagged
at once.
BLEEDING
Rosewood, particularly, but also mahogany and some other woods contain pigments that are soluble in
the solvents of lacquer. Also, some stains are softened and brought into solution by these solvents. To
complicate things further, certain fillers and sealers are softened by lacquer.
These are the reasons you should always use a lacquer compatible system throughout. Commercial
finishing involves lacquer base fillers and sealer. You cannot buy these materials at typical paint stores,
however. So, the best practices involving easily procurable materials are as follows.
- Use water or NGR stains. If you find it necessary to use a pigmented wiping stain, give it at least
forty-eight hours to dry. Otherwise, the lacquer thinners may act in the manner of paint and varnish
removers. - Give any standard paste filler forty-eight hours to set up hard, for the same reason.
- A safeguard is the use of thinned shellac as a sealer after stains or filler or both.
- Use a lacquer type sander sealer filler unless the wood is of such open grain that paste fillers are
required. - Let everything dry thoroughly, before lacquering, especially any oil resin or petroleum derivative
materials. - When you plan to use lacquer over rosewood or dark mahogany, use a thin shellac wash coat as a
sealer and do not sand it. The shellac will seal the pigment, keeping it from bleeding, and you might cut
through it if you sand, thus breaking the seal.
Lacquer rubs and buffs to a higher polish than you can get with varnish, which is one reason it is so often
used for small, elegant projects that look best with a high finish. The good rubbing quality also accounts
for speedy drying for the popularity of lacquer on most commercial furniture.
Whenever you want to keep the maximum natural wood color that is, without any of the darkening oil
finishes produce don't forget that lacquer itself is the whitest and the least darkening of all. On top of that
is the magical effect of lacquer lighteners, which leave the wood almost identical in color to its raw hue.