[sdiy] paia theremax

[James R. Coplin]

Ahhh, another finishing topic, I like these...

> > > Yikes !!! you are going to shellac ~before~ the stain ???

All the time, most classic finishes do exactly this.  Stain is basically a
paint and if you put it on the wood directly, it makes it muddy, hides the
figure and stains the field as well as the grain.  With stain, you only want
to stain the grain.  So, a coating of 2lb cut shellac after any dying and
oiling preserves the transparency of the wood's figure by sealing up the
field.  The grain is deep enough that the shellac can't fill it up without
numerous repeated coats.  Now when you apply the stain, only the grain will
take it up.

> >"A very thin mixture of shellac and alcohol can be used to condition
> >soft woods such as pine and fire before staining them for a uniform
> >and blotch-free appearance"

Kind of a different issue actually.  Any wood that you can dent with a
fingernail is soft enough that it needs conditioning first.  Don't assume
that a "hardwood" is actually hard enough to avoid this.  Balsa is a
hardwood.  I've even had some batches of walnut that came in soft enough
that I felt they needed conditioning.  

Softer woods have an uneven hardness and soak up your finishing products
unevenly (notice I didn't say stain).  A conditioner basically slows down
the absorption so you get an even finish.  This also means you generally
need some repeated coats to get the color as deep as you might want.  Dying
the wood really helps here.  I repeat, stain is paint!  You can buy a
commercial conditioner, Minwax makes one, or you can just use mineral
spirits to achieve the same thing.  The Minwax product gives you a good bit
of open time to work with it, mineral spirits work just as well but you need
to get a feel for when to apply the finish and when it has become too dry.
The best way to use it is to put a liberal amount on the piece and wait
until it is just past "wet" but not yet dry.  About at the point you can
pick it up and not really get any on your hands, but no later.  Finish as
usual.

Shellac is a brilliant finish (not clear shellac which really is only useful
as a binder for incompatible finishes in my opinion) and is making a bit of
a comeback.  It is a little fiddly but the results are well worth it.
Finishing is a bit of a process.  Don't think for a second that you can buy
a can of Homer Phonebees Minwaxy Magik and wipe it on a piece of wood and
get a traditional finish.  You won't.  I love most of the photos you see on
their materials.  It generally shows an amazing piece of furniture finish
with a smiling owner trademarked type person with the finishing product
pooled up on the other half of the furniture as if the product has magically
made the finish you see appear.  In actuality, the photo shoot just ruined
an amazing piece of well finished furniture by dumping their crap on it!

James R. Coplin