Violin Forum/Message Board

[sebastiaan56]

Hi everyone,

Im up to the bit where Im starting to scrape curved surfaces to refine the shape of the black plate. It seems to me that making scrapers is easy and they can be infinitely customised. There are a number of photos of "Stradivarius" scrapers on the net and this has got me wondering which shapes to make. What do people prefer?

I have a number of old saw blades stashed to use and am wondering if anyone can recommend the right material for scraping Spruce. Hardwoods are easy to work with but fibrous spruce is more of a challenge.

[Chad48309]

My scrapers are nearly identical to the ones in both of these pictures (thanks, Google Images). I made them out of very thick old saw blades. Just grind off any oxidation with your dremel until they shine, then hit them with Sharkhide. Keeps them from rusting on the outside, and since you're going to be burnishing and sharpening them (which will take the sharkhide layer right off), it won't affect your scraping edge. I put Sharkhide on all my tools, actually. Just seems like there's no reason not to.




_________________
-C.S.

[John Cadd]

The bare edge of scrapers can cut your fingers quite easily especially the cutting part.Make a fold of leather ( glued or stitched )to cover the bit you hold. It just slips over the back edge and keeps blood stains off the belly. Almost more important than a few scratches.

[Michael Darnton]

The top one is .014" thick, flexible but stiffish, and used for rough scraping of the plates, inside and out. The one below it, .010" thick, is for finish scraping and is more flexible. Bottom left is very thick, .20", and is for regraduating backs with the ribs on, or around the bass bar; the point is dull so it doesn't mess up what it touches, yet it can reach right up into tight corners. The center bottom scraper fits between assembled top and back for final scraping of the ribs, and the bottom right one is for finishing the scoop around the edges. On this one, the edge is sharpened, but not turned. It's thin, but it's so small it's not flexible.

The ones in the front look much larger than they are; the overall sizes, in the order mentioned above, are 3.5" x 1.25", 4.25 x 1.25", 3.5 x 1.25", 1 x 2.5", and 1.5 x 1.25". All of these are cut from machinist's blue steel shim stock

I have another stiff rectangular cabinet scraper for scraping ribs to thickness.



For scraping scrolls, I mostly use the tips of my knives.
_________________
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[Chad48309]

[DBurns]

This might help.

http://www.leevalley.com/US/wood/page.aspx?p=64762&cat=1,42207,64762

[Chad48309]

[sebastiaan56]

Thank you, that has been very useful. There is nothing worse than blood on spruce.

For scraping spruce does anyone have a preferred angle for the . Normally I roll a burr over a 90 degree edge. It doesnt seem to be working very well, ie more dust than curls,

[DonLeister]

45+- degrees with no burr, razor sharp.