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stuntrunt
07-30-2006, 01:42 PM
I can usually find the answer to any one of my questions using the search function, but for this one I seem to draw a blank...
I am a silversmith and I do a lot of metalspinning. Large discs I usually order to size and I can somtimes use a friend's circle shears. The smaller diameters (less than 4'') usually mean using a piercing saw though ;( I would therefore love to have something for those. I can't however seem to find what I need.

I think I might be able to tinker something together using this:
http://www.buitelaar.nl/comasy/templates/product.aspx?contentid=237&productid=1010
Which is similar or the same as this:
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=41081

Do you people think something like that might work? would it be strong enough to cut 1mm thick silver, copper or brass?
Any advice?

I'd like to thank all of you for all the advice you've given me in the past as I've learnt a lot brouwsing trough these pages.

JCHannum
07-30-2006, 01:55 PM
There was a two or three part series of articles in HSM a couple of years back on metal spinning. I recall there being some mention of a circle cutter in that similar to what you envision. I do not recall if build details were included, but it would be worthwhile to search the HSM archives. Reprints may be available.

Edit to add that I did look it up. The articles are "Getting Started in Metal Spinning", by James Riser, Jul, Sep & Nov, 2002. You might have to contact VP directly to see if they are available.

BadDog
07-30-2006, 02:24 PM
I sometimes use a trepanning tool or fly cutter with appropriate bit. I also made an adjustable circle guide (like a trammel point compass) for my plasma cutter. For your use, I think the trapanning/fly option would be the way to go, and it will easily cut 1 mm silver or other soft metals, I've used it on ~0.090 or so steel without problems, though the bit shape can be problematic to get a clean cut on thicker sheets.

Peter N
07-30-2006, 02:37 PM
Trpanning would do it.
Some pictures (not mine) at the links below.

http://audio.yachtsea.com/Show+Tell/RouterPlate-01.jpg
http://audio.yachtsea.com/Show+Tell/RouterPlate-02.jpg
http://audio.yachtsea.com/Show+Tell/RouterPlate-03.jpg

Peter

stuntrunt
07-30-2006, 02:56 PM
Trepanning would do nicely, were it not for all those precious chips!!! With the price of silver having almost doubled over the last few years... And trying to collect them is no use since I simply cannot risk the odd brass or aluminium chip to slip in with the silver when melting it. ( even a very small quantity of another material will reduce the silver to just "some expensive alloy"

panchula
07-30-2006, 04:45 PM
Can be found at http://www.jamesriser.com/RiserCircle/Shear.html

He has a lot of other neat stuff on his site, too.

Here's a similar HF sheet metal kit. http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=34104

-Mike

BadDog
07-30-2006, 05:24 PM
Darn it! Now I have YET ANOTHER PROJECT to get around to. Thanks a lot! :mad:

But that will make a perfect addition to all my HF bead roller attachments (some also still on that list).

;) :cool:

BadDog
07-30-2006, 05:42 PM
Never had more than a general idea how "metal spinning" was done, so I did a quick search to satisfy my curiosity. A couple of links for those like me that don't know much about it but are curious...

Tutorial (http://prl.stanford.edu/documents/pdf/spinning.pdf)
Pics of process. (http://allshops.org/cgi-bin/community/communityalbums.cgi?action=openalbum&albumid=9990109442635&ownerid=9990107622554)

stuntrunt
07-30-2006, 07:28 PM
Thanks for the responses guys!
And for making me feel as if I didn't do my homework ;)
I'd better get to work then...
I know I've been taking more than I've been giving but as soon as I've learnt something that you guys don't know already, I'll pass on the information...