SHELLAC EXPERTS ??????

[nick-p]

hi folks, been through the whole   "should i use sand/sealer"   argument recently and i'm left wanting to try SHELLAC but have had NO experience with it !!..  here is my question..

i intend to attempt a stain/nitro  wine red finish on the  "flame maple/alder"  bass i'm making. [ see pictures attached ].

problem is, i need the clearest, most transparent SHELLAC i can get for the purpose.  would that be BLONDE ?  and how should a shellac-virgin go about the task ?  how  many coats ?..  .    nick  [ in UK ]

[Jeff Highland]

No I'm in Australia., they just had a good price.
Customs must have been curious about the baggie of offwhite powder.
Yes a test piece is the way to go

[Howard Klepper]

I now find myself agreeing with Rusty, below. Had to happen eventually, I guess. I didn't realize you are the same guy who was asking about sanding sealer on that other thread (I still think it would be of no benefit to you). What I suggested there was that if you wish to use something for the purposes of a sanding aid--to raise grain and lock in loose fibers prior to final sanding and topcoating--shellac has advantages. also that if you are not going to sand that first coat back to wood, sanding sealer has disadvantages. I don't want to reopen that discussion, because now you are asking about something quite different from the need for sealers and the merits of different seal coats. Which shellac is the most colorless isn't going to matter to you for this finish.

There are two ways to go on curly grain, and they are matters of taste, initially. If you stain the wood, it will soak up stain where the grain runs out and take much less stain where the grain is parallel to the surface. This changes once for each curl. Finishing this way increases the light/dark and color contrast of the curls. The downside is that the bands of grain runout get muddy with stain, the the chatoyance of the wood is diminished. The curls stand out for contrast and color depth, but they lose some the three dimensional quality that comes from the light reflecting off the fibers at different angles. There also is less of a reversal of light and dark when you look from the other side.

Putting all the color in the film does the opposite. Preference between the two is a matter of taste.

But there are compromises that can get you more or less of both worlds.

A simple one is to sand very fine before staining, and to raise grain (e.g., with shellac) and then sand back to wood using fine grits. The wood will absorb a little less stain than if you had not sanded so fine. This isn't really any kind of compromise; it's what you should do even if you want maximum contrast. In that case use a non-grain raising stain and lacquer right on top of it when it dries.

Another is to stain and then do a light sanding back of the wood with fine grits. This removes stain more from the areas of grain parallel to the surface and can increase the pop of the curls and also increase the chatoyance of the wood. The "tigers eye" finish is done this way (with a dark or black stain). A grain raising stain is an option here, since you are going to sand the wood after staining.

Another move in the direction of more chatoyance/less contrast is to "condition" the wood so it is partially sealed and absorbs less stain. There are commercial products made for this, and you can also use thin shellac.

Getting any of these to look really good requires skill and practice. There's no automatic, follow-the-steps and get an assured outcome. Closest to that is no stain on the wood and transparent dye in the film.

[nick-p]

lots to consider there howard. [ especially as this is my first attempt at finishing ]. i have quite an interest in your last suggestion [ no staining prior ]. for that particular method, should i use a sealer of some sort before my "dye in the film" approach ?.

[Howard Klepper]

You don't need it for adhesion, but I always use a shellac coat so the dye doesn't penetrate the wood. This is because I have heard that some folks, sometimes, end up having to remove all the finish and start over. Just in case that might happen to me some day. ;-)

[Russell Vance]

Howard, thanks mate, I think we were butting heads about apples and oranges here, your last answer encapsulates and distills many years of valuable knowledge about this particular finish genre - I also compliment you on your dedication to acoustic finishes which are, as you say not an easy style to get right. I note that you have tagged just about every particular trade-off in the schedule and have nothing to add other than emphasizing just how critical the choice between direct staining versus shader is to how the figure appears and what depth you end up with. Happy to be in such fine company.

Pierre also makes another observation as well regards sticky/thick nitro - we generally shoot lots of skinny coats of 50% thinned nitro to get a good gas out and a good coat to coat bond and our particular nitro product needs some time between coats to achieve stability. We also use a propriety thinner from the same company which is designed for the nitro product we use - and the chemist says this is important.
Pierre, the guitarist playing the quilt top is Wayne Withers of 'Tonk' - a great test pilot and a great guy.
I have not had success shooting nitro coats close together in time but Gibson does - they also use a softer nitro than us. But, most of these finishes on the low end stuff is not nitro and stays glossy regardless. If it was easy everybody would be doing it.

[Pierre-Antoine Roiron]

Hahaha!!!!
That is funny, I was quite sure the guy was Matt Damon!
When you say :
I have not had success shooting nitro coats close together in time but Gibson does
I could add that maybe it's why their nitro finish becomes so sticky?

[Donald A. Fortune]

Good way to go Howard-- Somehow I always end up puting about a half dozen spit coats of clear shellac on all of my finished products, then deside what I will do for final finish.
Peace, Donald

[nick-p]

i think it will pay me to go for the spit coats [ does that mean thin coats? ] of shellac on naked maple before spraying coloured nitro over the top as it's my very first finish attempt [ safest bet i guess ] . thanks to all of you for advice, even when you are not answering me directly [ and kinda arguing with each other ] you are shaping my thoughts for making a descission. you know, it's a great shame that i will probarbly only make a few guitars over the years. by the time i've paid for the wood,pickups, hardware and finishing products i could have just gone out and bought a finished guitar !!... ok, i'm buying the finest parts available but i thought that making your own always meant paying less..... like making clothes etc.. just not true with instruments.

[Randall Curtis Bowman]

You may want to try a different approach than shellac. Faced with an exceptionally cold winter last year, and a hard-to-heat work area, I grabbed a pint of MINWAX Wipe On Poly. It took about 12-15 coats, once in the morning, and once at night, but it resulted in a nice gloss, almost like a super thin nitro finish. You may have to seal any stain in prior to using so it doesn't smear the color, but on natural wood, it's just killer. Brings out the chatoyance in curly and quilted figure, and has a decent build. The best part is the ease of application, and ability to smooth out prior defects since each coat is so thin. There are many other kinds out there, and you can make your own as well with some standard poly, a little linseed, and some naptha (makes it dry fast.) Good luck.