PDA

View Full Version : Slitting coiled wire



Hamish Lonsdale
24th Oct 2007, 09:23 PM
Friends, I need some help.
My wife’s current hobby is making jewellery items from wire, slit and formed into round links like chain mail. These she can buy at huge expense.
I obtained 10m of painted copper winding wire for electric motors from a mate, made up a mandrel of the correct ID for the desired product, engaged backgear on the Myford and wound a perfect coil. http://www.woodworkforums.ubeaut.com.au/images/icons/icon7.gif
Then the trouble started. I needed to slit the coil along its length to produce many small rings.
I started by making a chuck mandrel that held an HSS circular slitting saw working with the coil held in a Record machine vice shimmed and set up on the cross slide. It did not work, as the clamping pressure needed to hold the coil distorted and damaged the wire.
Next I tried clamping the coil (mandrel included) in the vice, and using my jewellers saw to slit it longwise. A lot of hard work, and a very rough job was the result together with a blunt saw.
I next tried the Dremel with a cutting off disk, but this heated up the wire to the point that the coating changed colour.
Has anyone got a suggestion as to the proper method of slitting? Any other solutions?
Best wishes, Hamish.

China
24th Oct 2007, 10:55 PM
Now you know why it is a huge expense, I have only ever seen it done with small piercing saws etc. by Jewelers and with small hacksaw by chaimailers but on the other hand I'm sure there would a mechanised way of doing it, maybe a set of soft jaws with a groove the size of the coil might minimise distorsion

burraboy
25th Oct 2007, 07:24 AM
A friend of mine in Lithgow specialises in making links for mail as well as finished articles, clothing and jewellery. If you are interested in checking out his prices or talking to him about the techniques he has developed for making them, I can give you contact details by email.

DavidG
25th Oct 2007, 01:07 PM
Pull the coil off the mandrel and then cut the links off with a pair of fine jewelers side cutters.

BobL
25th Oct 2007, 03:10 PM
What about a mini guillotine arrangement. Make a steel mandrel with a hack saw blade thickness slit cut along its length, wind on the copper, leaving a couple of inches of slit showing, slide a sharpened hacksaw blade into the exposed piece of slit and then use a vice to gradually force the blade to slice through the coils?

under thumb
25th Oct 2007, 07:30 PM
In high school we did it like yourself on a mandrel that had a pre cut slot in it, so it was easy to run a jewellers saw along it to cut copper and brass. I dont know what variation there are between jeweller saws, as it is not my area, but the ones we used had an incredibly fine, sharp blade that broke very easily. Maybe you could investigate different blade types from a jewellers supplier.

Hamish Lonsdale
25th Oct 2007, 08:56 PM
Thanks for that. I would very much like to talk with him.

Best wishes, Hamish.

Please contact through PM or email through User Profile.

mingus
25th Oct 2007, 10:57 PM
Pull the coil off the mandrel and then cut the links off with a pair of fine jewelers side cutters.

When i was in high school a guy made a chain mail shirt using that exact method. I have no idea whether he was using copper or not though.

Frank&Earnest
26th Oct 2007, 11:38 AM
Another option is to leave on the mandrel and cut with a sharp chisel. With a bit of care it is a neater cut than with wire cutters, because of the thinner bevel (say 15 degrees) that you can sharpen often.

burraboy
26th Oct 2007, 10:39 PM
Just for the record, the set-up i have seen in use involves the original suggestion, ie. a slitting saw set up on a mandrel in the lathe. The coil of wire is fed onto the slitting saw along a circular mandrel by a hand powered drive mechanism. That's for steel rings anyway, smaller or softer rings can be cut by hand. I understand the ring count is approaching 2 million using this method.

Hamish Lonsdale
28th Oct 2007, 08:49 PM
Friends,
I would like to say 'Thank You' for all the suggestions. The jewellers wire snips seem to be the go, but I am following up with Burraboys contact as well.
BW, Hamish.