Shellac Shack

Using Shellac as Adhesive in Wooden Boats

I got a call today from a company that builds wooden boats. They were inquiring about grades of shellac to use as a adhesive between the two wooden layers on the hulls of boats. This is a traditional use for shellac that has gone out of favor in the last 40 years with the advent of modern glues.
This call was spurred by an article in a wooden boat magazine ( I happened to see this article several weeks ago and made a copy of it), It seems like the use of shellac for this purpose could take off among the many small companys that build wooden boats.
Anyway, the man I talked to wondered what grade of shellac would work best. They want something with little refinement and something that is as inexpensive as possible as the need a very heavy cut for this adhesive.( Woodworkers use a 2 pound cut - he will use a 9 pound cut)
We discussed what would have better adhesive qualities for wood - dewaxed or waxy. I told him I thought dewaxed would work better. What do you think?
If waxy would be better, we thought he could possibly go with a seedlac. I told him about the debris involved and he didn't think it would be a problem.
Lately I have been wondering what I can do to increase the market for shellac and this discussion shows up as a real possibility. I am planning on advertising in this wooden boat magizine's next issue and continuing to look for further markets for shellac.

Old Shellac Flakes

The gooy mass indicates the flakes are getting old.
I do not have personal experience with this, but an old french polisher explained the following to me:
First thing you would do is the metal test. Put a drop on a smooth hard surface - painted metal or glass, wait a half hour or so and see if the solution drys and gets hard. If it goes, you can strain out the goo and use the rest.
The french polisher says that the resultant solution is as good if not better that fresh flakes because it has polymarized to some extent and will produce a harder finish. The bottom line, of course, is this is just his opinion and experience. Of course you are no longer sure of the cut as you have left some of the shellac resin behind.
I'll let you make your own judgement on this, but since you have already used the everclear, you might at least experiment with the results and see what you think.
If you discover anything interesting, I'd appreciate hearing the results.
The old dry flakes can not be reprocessed easily, if at all.

Shellac is Food Grade

I think your main concern is sanitation/free from organisms (a concern since it comes from india)

There is a bleached dewaxed powdered shellac that is derived by percipitation. There is powdered shellac produced by dissolving the raw material in industrial alcohol (nearly 100%)and filtered. Then there are the flakes which are produced by the alcohol method.
The fact that the shellac is refined using alcohol, then put in alcohol solution by the end user makes me think that it would be germ free. I personally have no qualms about handling the stuff. It fells pretty natural.
I do not carry the two powdered kinds mentioned above, but can get it. mininum order of 50 to 100 lbs.
I do carry the flakes. You would probably want to use the super blonde as it is the clearest and the most filtered.

Shellac Uses

I recently talked to a customer who uses in his formulation of an adhesive for his electronics business. He says that it works as well as the new adhesives, but that he prefers this method.

I heard today about a man who uses shellac to refurbish pipe organs as well asbuild new ones.

We have also sold shellac to wooden boat restorers who use shellac as an adheaive to hold the "bungs" that cober the screw heads in the hull planks.