Tool Modification Question

Hi everyone, I just ordered these link forming pliers and I want to use them to stretch decorative bezels that have been formed using dies and a hydraulic press. The problem is, you can’t really fit two full circles in an oval. So I want to ground of the round pegs to make them flat on one side so I can easily stretch a nicely proportioned oval. The pegs appear to be maybe cast iron? Do you think I need to worry about getting them too hot during griding and loosing the temper?


Those look like Swanstrom pliers. If so and if you bought them from Rio Grande call Rio and ask for advice. There are experts there on pretty much everything jewelry tool related. The tool geeks, like all geeks actually love it when someone asks them for advice on their particular area of expertise.
-Jo

I understand your questions and, like Jo suggests call Rio, but it seems to me that you will be getting kind of a flattened oval if you spread the pins very much regardless of the shape of your pin. I have a slightly different link forming plier from Rio, Item 1110001. It has the same plier, but there is a telescoping multi hole platform on top of it that lets me configure different shaped links with more than two points. I have made additional pins out of common nails turning them on my lathe to fit the anchor hole. I am still not sure how I would get a repeatable oval out of it without hand shaping each one after pulling the link tight in the plier. Maybe I am missing something…Rob

For 8x12mm to 26x34mm I use this oval mandrel:

Oval Large Bezel Mandrel-8mm X 12mm to 26mm x 34mm OMO-Made in Italy | OttoFrei.com

There is also this size:

Oval Bezel Mandrel-4mm X 6.5mm to 15mm x 20mm Made in Italy | OttoFrei.com

For 32 x 38mm to 63 x 76mm ovals there is this:

Cast Iron Oval Bracelet Mandrel - RioGrande

I have one like that but it starts at 25 x 34.5mm. I don’t remember where I bought it. If you need that range check the usual sources, including Gesswein and Contenti.

Neil A

Here’s what we did when a student here wanted sturdy ovals for a bracelet chain, I repurposed a 1/2" spanner and sawed a slot in the end. Note that mandrels need not be the perfect shape of the required oval:



Neil…I have a small oval shaped mandrel and use it often. When I need a larger oval shape, usually for a bezel, I just use a pair of large chain nose pliers and slowly form the oval around the outside of the pliers as I carefully open them. I also use the stone as a mandrel shaping the bezel around the stone with a rawhide hammer finishing with a pair of half round/round nose pliers. If I am making a bezel, I do so knowing that, regardless of how accurately I have the bezel shaped and how annealed it is, once I solder it to a backplate, something will have moved and there will be some interference in setting the stone. I am always prepared to do some adjustment to the stone below the bezel line to get it to fit the bezel. The other option is too large a bezel and the possibility that the bezel to stone gap will be uneven moving around the stone. Then I have to be creative about how I close the bezel keeping everything symmetrical if it is an oval stone. Oval links are a different story. Once the basic oval shape is made on a mandrel or other shaping device, you can always adjust it using pliers and forging on a small anvil point. This becomes a challenge if you have already assembled the links and need to reshape them. Lots of options, lots of fun…Rob

Everyone has good alternate tool suggestions, but it sounds like you’ve already bought these?
I would think most bezels of silver or jeweler’s brass would be soft enough that you shouldn’t need to worry about the temper. Unless you’re working with some very thick stock, I think the pegs should stand up to pulling on a bezel or a wire just fine.

If there’s a size you think you’ll use least, maybe the largest or smallest, you could do a test run on just one set.

I’ve modified a handful of old dremel bits (and none of them fancy carbide to begin with) for use as various pushing and scraping tools for silver, and they’ve all held up fine.