On Sat, 20 Dec 2008 12:25:00 -0600, Bob S. wrote
(in message ):

Been awhile since I've posted here but now that the economy has gone
belly-up, my job followed and I now have some free time to catch up on
all those little projects I've been meaning to do.

One is a broken chair from a dining room set my sister asked me to
repair. There are 3 broken rungs about 14" long which I need to make.
Long story short - I'm not good at making duplicate spindles freehand.

Using a Delta mini with the extended bed. I've looked at a number of
duplicators on the web but really can't justify the expense for a
one-time use. Googled for how to make a duplicator and found several
shop made units that would require a master machinist to make. Nice -
but way overkill for what I need.

Looking for a basic design that will work for these short, decorative
chair rungs. I have a fairly well equipped wood working shop and
access to a friends metal lathe and welding station - if needed. I
tried convincing him he needed a CNC but he saw right through that....

Anyone make a duplicator that they would care to share their design
ideas ?

Thanks,

Bob S.



A kind of a poor man's duplicator is just a template or pattern of the
spindle you want to make, mounted opposite the spindle . What you will have
is your tool rest on one side of the spindle - nearest you... and on the
other side of the spindle is your pattern. Actually, it is the "negative" of
your pattern. Call it a template, if you like. A peak in the pattern is a
groove in your spindle, and a low area in your pattern corresponds to a high
point on the spindle.
The pattern shows you where to cut and where not to cut, and how deep.
Use an outside caliper and your parting tool to cut reference points on your
spindle at various places like the end tenons and a couple of places near the
middle.

Your pattern is mounted just fractions of an inch from your spindle, and you
now have some target-depth grooves cut with your parting tool, corresponding
to certain points on the pattern.
I am not skilled enough to use just a skew to do all my spindle shaping, so I
must resort to the use of various scrapers for the fine shaping work.
Watching the spindle as wood is removed from it, and observing the gap
between the spindle and the pattern as I work, I just sort of cut away
anything that does not look like the pattern.

You need to make the pattern of something durable like sheet metal - maybe
bash out a piece of stovepipe or a section of your neighbor's roof gutter.
Then the pattern needs to be mounted on a stand which will hold the pattern
clode to the target spindle. You need to be able to move the stand around, to
see how the pattern fits the target spindle from time to time. I learned that
the best time to try fitting the template to the target spindle is when the
spindle is not turning. The stand has to be mounted in such a way that the
lathe vibration does not make the pattern dance around.

I hope this helps a little. Further, I hope the Turners here do not think me
daft. (in this matter, anyway)

tom koehler

--
I will find a way or make one.