"Proctologically Violated©®" wrote:

Not only are you way over-estimating my abilities, you are scaring me.


I didn't realize the master jaws were missing.

Wes

On Sep 3, 2:05*pm, Wes wrote:

I didn't realize the master jaws were missing.

So, to mate to the scroll you need the outer face of each tooth to
have the
radius of the innermost scroll diameter, and the inner face of each
tooth
to have the radius of the outermost scroll diameter (that it
might actually mate with), and the teeth must be slightly
canted (depending on the lefthand/righthand scroll, that can
go either direction).

How did anyone do that before programmable machine tools?

How do you do it WITH programmable machine tools?

On 2009-09-04, whit3rd wrote:
On Sep 3, 2:05*pm, Wes wrote:

I didn't realize the master jaws were missing.

So, to mate to the scroll you need the outer face of each tooth to
have the
radius of the innermost scroll diameter, and the inner face of each
tooth
to have the radius of the outermost scroll diameter (that it
might actually mate with), and the teeth must be slightly
canted (depending on the lefthand/righthand scroll, that can
go either direction).

How did anyone do that before programmable machine tools?

My guess is the same way they made the scroll plates. Mount the
jaw blanks in proper relative position in a fixture which goes where the
scroll plate blanks go in a rotary table or index head geared to the
X-axis leadscrew on a vertical mill. This will make the teeth just
right at one size setting only. Then use a lap made on the same machine
which made the scroll plate (but, of course, a softer material), and lap
the jaws through the range of their adjustment.

How do you do it WITH programmable machine tools?

You can probably eliminate the lapping phase, and just program
the end mill to make multiple passes to get the inner and outer curves
right.

Enjoy,
DoN.

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On Sep 3, 10:33*pm, "DoN. Nichols" wrote:
On 2009-09-04, whit3rd wrote:

On Sep 3, 2:05*pm, Wes wrote:

I didn't realize the master jaws were missing.

So, to mate to the scroll you need the outer face of each tooth to
have the
radius of the innermost scroll diameter, and ...

... [even] WITH programmable machine tools?

* * * * You can probably eliminate the lapping phase, and just program
the end mill to make multiple passes

It sounds like an only-in-mass-production effort in any case.
For a found-item rebuild, one can cheat and make light-duty jaws
using
a row of pegs (basically, just drill for a series of press-in dowels).
Don't use hardened dowels, brass pins will be suitable and the
scroll won't accumulate dents.