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Old 12-31-2016, 04:12 PM   #1
Waunakee
 
Join Date: Sep 2016
Posts: 3
Default Is this the original finish?

I have acquired a ca. 1916 prop that has inlaid brass plates indicating that it was used on a JN-4 with an OX-5 engine (see accompanying photos, six with this post and then six more to follow). It has the original labels on the backside of the prop and it was manufactured by the B. Schoninger Company, a New Haven CT piano making firm.

Ii is in very good condition, but I'm trying to determine if the current shellac finish is original. I don't want to do anything to an original finish, but if it isn't original, I believe I can improve upon it.

The finish is very unusual in that it has a multitude of fairly large "bumps" in it. To me, it looks as though the shellac flakes or buttons were not fully dissolved in the alcohol solvent, nor was it strained, before using it. If it was a piece of furniture, it would obviously not have been finished like this. However, has anyone seen evidence on other props of that era that a manufacturer would do such a poor job of finishing it?

Also unusual about the finish is the fact that there are a number of round, regularly spaced and sized impressions in some areas of the shellac that look as though it was wrapped in bubble wrap at some point and that either the finish was soft, or there was a chemical reaction between the shellac and plastic bubble wrap that caused the impressions in the finish.

Finally, the front side has a very different appearance on one side only; on that side, the finish is black in color and shows crazing.

If anyone has something to offer about the originality of the current finish, or any other general info about this prop, it will be greatly appreciated. I lean towards carefully removing and replacing the shellac but leaving the copper tips black (which I believe is the original finish). However, I'd hate to do so and find out too late that this poor quality finish was original.
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Old 12-31-2016, 04:17 PM   #2
Waunakee
 
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Default final six photos to go with post

Here are the final six photos
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Old 12-31-2016, 11:11 PM   #3
Dbahnson
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Default

It's original, and should be kept that way. What you're seeing is "alligatoring" of the original finish, which is caused by contraction of the original finish causing well-spaced cracks that result in clumping.

While it would be easy to rejuvenate it, it's MUCH better to leave it as is, especially as it has original Shoninger decals. You almost can't possibly make it worth more than it is in its present condition. A gentle application of beeswax will help it last longer without detracting from its original condition, but be careful about rubbing it in too vigorously.

Nice prop!
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Old 01-01-2017, 12:01 PM   #4
Waunakee
 
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Default Thank you...

Thank you for the information. I had thought that "alligatoring" was used to describe the crackled finish that you sometimes see on old furniture, an effect that can be replicated/faked by using a coat of liquid hide glue under a topcoat of paint. This seems different to me - there are no minute cracks in the areas of the finish, but there are large nodules of undissolved shellac, even bigger than those you would see on 60 grit sandpaper. Again, there are no minute cracks in these areas. It sure looks as though someone put on a coat of shellac that wasn't completely dissolved (or strained). The net effect looks as though someone had sprinkled large nodules of shellac over a fresh coat of shellac. A few of the posted photos show this, but I could also post a macro photograph of the finish, if that would help.

(The blackish area I described is different from the rest of the prop; that are does look alligatored).

I have worked in the past with shellac made from dissolving flakes in denatured alcohol, and if you don't completely dissolve the flakes or strain the shellac to remove the small globs, it looks very similar to this. If you could, please review the photos again and see if you might agree. Another clue is that there are a few areas in which the shellac is VERY thick and dark, adjacent to areas that look almost as though someone ran a squeegee against a newly coated area, pushing the finish into a small hill.

Respectfully,

Mike
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Old 01-01-2017, 02:58 PM   #5
pmdec
 
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Hi,

Dave is right: this aspect is from ageing varnish in some kind of environment and is very often seen on props which have been "exposed" without caring to "atmosphere". Some examples attached.

Happy New Year to all!
PM

EDIT: Added after a remark received by mail:
On the third pic, you can see that the Ratmanoff decal has remained flat. It is because the decal has "protected" the varnish. If the "bumps" were there when varnishing, the decal would show the same "nodules".
I suspect those "nodules" are from heat excess or direct sunlight for hours or, perhaps, some "care" applied on the prop wich has soften the varnish. The darkest color of these spots are, IMHO, because the layer is thicker.
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Last edited by pmdec; 01-06-2017 at 07:09 AM.
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