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Hey Colin, where are you getting shagreen from? Common woodworking and finishing suppliers, or do you catch your own sharks and rays?

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Joshua, I don't think that the woodwork suppliers have been keeping it for a couple of hundred years now!

A friend of mine, David Hume, who builds the best violins in the world, and who has rebuilt and restored more Stradivari than any other luthier, sometimes uses it on restorations. I actually did make my own from the skins of Spur Dogfish and Thornback rays, that my brother-in-law caught in the Channel. Carefully stretched and dried, it is very effective.

David has actually found 'teeth' of shagreen in Cremonese violins.

Question, what would the 19th century Spanish builders have used as abrasives, they couldn't just go out and buy 320 grit paper could they? I'm trying to build as authentically as possible on the next one and have been puzzling this, I assume they'd moved on from shark skin.

Historical building is such fun, back to basics, I love it!

Colin Colin S39051.725787037

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Colin,

I wonder about this too. Apparently commerical abrasives were available by the 1890's or so. My guess would be coarse pumice but mostly scrapers and planes. Probably also files sharpened in buckets of urine (!). Also, I would imagine shagreen was available. Instrument makers (or at least cabinet makers) had a lot of interaction it seems.

A quick web search revealed a couple things. Emery/Black Sand is another naturally ocurring abrasive.

Also: According to wikipedia: Glass paper was in use by 1833 and there was a patent for sandpaper in 1834.

I have never seen any mention of sanding scratches on guitars before 1900, though have seen mention of toothing plane marks and other things.

If I ever catch me a shark, I'm mounting the head on a plaque, using the skin as sandpaper, the fin for soup and the teeth for necklaces. I hate sharks (only takes one to ruin your surfing session... or worse...)

You're more dedicated than I to be using shagreen! I made some pretty nice herringbone today for a back inlay using no power tools or sand paper, just because you made me feel guilty about my power buffer and use of sandpaper.

You gotta try it though. Sand a french polish level with dry 1500 grit, then 3m "finesse it" on the power buffer... unfortunately with customers the end justifies the means!jfrench39051.892037037

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