After reading Bob Flexner's book Understanding Wood Finishing
I decided to try a high build finish. I learned that spraying a
perfect finish was truly impossible, but some experimentation with rubbing yields
astounding results. Bob claimed that the clearest finish is obtained with
Lacquer, so this is what I use. I have learned that musical instrument
makers also use lacquer. With these methods it is possible to obtain a
mirror flat finish equal to the highest quality dining room tables.
* Warning! - Always use a respirator and prodigious
ventilation when spraying lacquer. It can go "boom". It
will kill brain cells. It will provide a splitting headache.
* Tip - Use full spectrum flourescent lights when spraying and
rubbing lacquer. These are the ones that simulate sunlight. This makes the
hue of the finish much easier to see.
This is my approach:
1. Spray 1-2 coats of lacquer.
2. Sand flat with 220 grit sandpaper. The purpose is
to flatten any grain standing upright after exposure to the finish. I use
my random orbital sander with a vacuum attached for this.
3. Spray 8-10 more coats of lacquer. Subsequent
coats will dissolve into the previous coats so there is no need to sand between
coats. Lacquer typically dries in 30 minutes, so this operation can be
performed in 1/2 day with ease.
4. Block sand with 220-320 grit sandpaper until the finish
is flat.
5. Spray 2-3 more coats of lacquer.
6. Allow lacquer to dry completely. I don't have
this one scientifically explained yet, but it seems that when the lacquer stops smelling
bad then it is completely dry. The advantage to allowing the lacquer
to dry completely is that it won't clog as much sandpaper when rubbing. It
seems like 1 week+ will allow the lacquer to dry completely.
7. Wet sand with 800 grit paper. The purpose is
to flatten the orange peel and dry spray. It helps slightly to sand with
the grain, but this is not completely necessary. Spray a little water on
the surface. Sand a little. Wipe dry to check your work. Spray
a little. Sand a little. Wipe dry and check your work. It will
be obvious in reflected light when the finish is rubbed flat. There won't
be any shiny spots from the glossy finish remaining..
8. Wet sand with a 3M 1500 grit pad. I use a
Porter Cable 7336 for this operation. I also use a household sprayer.
An old window cleaning container works well. Spray a little. Sand a
little. Wipe dry to check your work. Spray a little. Sand a
little. Wipe dry and check your work. It will be obvious in
reflected light when the finish is rubbed good. The other possibility is
to dry sand with 1500 grit automotive paper. If sanding by hand, I
recommend 1200 grit then 1500 grit automotive 3M sandpaper.
9. Rub with 3M Perfect-It III Machine Glaze and a glazing
pad. I use a Porter Cable 7336 for this operation too.
The result is a deep clear mirror-like finish.
I haven't tried many lacquers, but will summarized my
preferences herein. The Rudd high solid content lacquer (@$25) to equal
the Sherwin Williams lacquer (@$35). My previous preference is a Rudd
pre-catalyzed lacquer in a "90" gloss. It dries slightly quicker than the
afore mentioned lacquers and the finish is harder too. There is no change
in clarity. My current preference is Sherwin Williams post-catalyzed
lacquer. It requires a sealer, but the final finish dries slightly harder than the Rudd pre-catalyzed lacquer.
I tried Deft (Deft is Lacquer), and it is quite soft by comparison. It has an acceptable reputation for
a commercial product and the small spray cans of Deft work nicely to fix
mistakes. Additionally, Deft has some retarders that make it viable for brushing.
It is theoretically possible to obtain a decent finish with a brush.
If the Lacquer is labeled "water white" it will likely look much
better with a tint. I use a honey amber tint in my water white lacquer. It works
fabulous and provides a slight warmth to the finish.
Please let me know if you have any questions regarding the
information presented above. There is probably room for clarification on
some items.