Loshem
Oud Lover
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Rosette cutting
I was just curious because I can't seem to find any information on the method of rosette cutting. I realize it depends on the design but How do you
get a jeweler's saw to the inside of the rosette without cutting into the center? What methods do some of you oud builders use to get precise cuts by
hand?
-Losh
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carpenter
Oud Junkie
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I have the design drawn on the wood, and drill small holes where the voids will be. I thread the blade through the hole, tighten it up in the saw, and
saw away. Same technique for a jeweler's saw or a power scroll saw, I would imagine. I've seen the lute guys use knives to cut rosettes, and I know
laser cutting works. There are probably other ways, but that's how I do it.
I go in after sawing and clean up where necessary with X-Acto blades and needle files; that can take nearly as long as the sawing.
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Loshem
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That makes sense. What works best for cutting if you are using wood for the rosette? Is a jeweler's saw best? Are there different blades for different
materials like for larger saws? Thanks for the reply.
-Losh
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carpenter
Oud Junkie
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I use a jeweler's saw because it's quiet and inexpensive. A power scroll saw is the same thing, more or less, but motorized. Up-and-down is the
idea.
I've had my jeweler's saw for maybe thirty years, from back when I was doing silver work, and I had a small cigar box of blades; now it's even
smaller. The wrappers are gone now, so I'm not exactly sure what size I'm using - 5/0? - but I found this handy chart:
8/0 .0063" .0126" 89.0
7/0 .0067" .0130" 84.0
6/0 .0070" .0140" 76.0
5/0 .0080" .0157" 71.0
4/0 .0086" .0175" 66.0
3/0 .0095" .0190" 61.0
2/0 .0103" .0204" 56.0
1/0 .0110" .0220" 53.5
1 .0120" .0240" 51.0
2 .0134" .0276" 43.0
3 .0140" .0290" 40.5
4 .0150" .0307" 38.0
5 .0158" .0331" 35.5
6 .0173" .0370" 33.0
7 .0189" .0400" 30.5
8 .0197" .0440" 28.0
Blade classification; blade width; blade depth; teeth per inch. All I know is I can't see the teeth; I have to feel for which way they're
pointing. You youngsters probably won't have to get the magnifier out. They come in bundles of 24 or so, wrapped in thread. Not a very big bundle
...
You'll also need to make one of these supports for the workpiece. Mine is a piece of 1/2" plywood, 2 1/2" w., 1/4" hole. Clamp the dumb end to the
work bench, kitchen counter, dining table, with the notch facing you. The idea is that the saw goes up and down in the hole, handle down, teeth facing
down and away from the frame, and the workpiece moves. Ideally.
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carpenter
Oud Junkie
Posts: 248
Registered: 8-30-2005
Location: Eugene OR
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Here's a drawing of a saw: I first clamp the blade (teeth pointing towards the handle and away from the frame) at B, with the other end just touching
the clamp at A; the screw at C is the adjuster for blade length. I thread the loose end of the blade through the workpiece, then I put the B end of
the saw firmly against an edge of the bench or whatever, and press the handle - A - end towards it, and tighten the screw at A. The frame is flexible
and springs back putting tension on the blade. (I tend to press on the handle with my chest while tightening the screw, but you'll find your way -
it's how I was taught. Don't hurt yourself.) The blade should have a nice high-pitched "ping" when plucked.
Now you're ready to saw; keep the blade vertical as much as you're able with the workpiece on the support, make nice long strokes, and don't force the
cut. The teeth are doing their best; pushing the blade into the cut won't help much, and you'll break more blades than usual. Yes, you'll probably
break blades at first, but it's a learning process. You'll get the hang of it soon. If the going gets really slow, you're probably sawing
into the support. Careful there, and don't snap the blade.
If I have a V corner to saw into, I drill the (1/16") hole in the piece close to the corner, and work into it from both directions. The waste will
drop out, and there's more room to turn around. Drill holes wherever needed. Try a test piece, and you'll see how it goes; use your head and learn.
Nobody's born knowing this stuff, after all.
Practice; wood's cheap. That's all I got. Best of luck!
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carpenter
Oud Junkie
Posts: 248
Registered: 8-30-2005
Location: Eugene OR
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<< Are there different blades for different materials like for larger saws? >>
Sure; you can find a lot of information on the internet.
But - bigger blades aren't necessarily for larger saws here; the more teeth per inch, the faster the cutting, but the cut will be somewhat rougher,
with more splintering on the back side. There's a balance between the thickness of the workpiece, the material, and the teeth per inch; a blade with
80 tpi working on a 1/2" piece of oak? You'd be sawing 'til Doomsday. The comments above are based on my working with hardwoods (mostly), about 1/8"
thick or less. There are jeweler's saws with deeper throats (blade-to-frame), but basically the blade is determined by the work.
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carpenter
Oud Junkie
Posts: 248
Registered: 8-30-2005
Location: Eugene OR
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Mood: brimming with hope
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R&D Dep't Report: I borrowed a friend's power scroll saw, just to see how it went, and I'm going back to my poky, slow (quiet, cheap ...)
'Armstrong' jeweler's saw. The power saw was too jumpy and nervous-making for my taste, not to mention cumbersome and time-consuming to undo and refit
the blade every piercing cut. Sheesh! (Okay - it's low-end Jet saw ... still - this is 'progress'?)
Don't let that stop you, though! I know Jameel makes lace from bones with his deWalt scroll saw. (Now there's a recipe for success: Jameel, time, and
a nice tool!)
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