Length that silver will stretch

[theresa]

A question for Dennis please.
I saw your answer somewhere on the Forum, but unable to locate it.
I am going to roll out a 4mm square section of silver wire to 5mm x 3mm and wondered by how much it will lengthen. Is there a formula for this type of exercise?
Thanks Dennis
Theresa

[Dennis]

I'm afraid there is no formula Theresa as there are too many variables.
For instance if you roll it lengthwise it might long have exceeded 5mm in width before it is 3mm thick.
The slightest change in direction can also make it wonky

Your best bet is to order 3mm sheet, cut 5mm wide. It will be slightly twisted from the bench shears, but you can normally deal with that. It will also be slightly pinched along one side, and if that matters, order a mm wider and file that off.

Alternatively order a near size in rectangular wire, such as 4.8 x 3.2. Regards, Dennis.

[theresa]

Thanks Dennis

[joella]

Hi, Theresa,

Maybe being a bit cheeky here, so sorry I'm kind of hijacking your thread, probably shouldn't do that! But, I remembered you posting a thread about torch firing enamelling - and I was wondering if you got around to having a go and how it went? I''d love to hear all about it, and see some pics if you have any (hope you don't mind me asking).

Thanks
Sue

[theresa]

Hi, Theresa,

Maybe being a bit cheeky here, so sorry I'm kind of hijacking your thread, probably shouldn't do that! But, I remembered you posting a thread about torch firing enamelling - and I was wondering if you got around to having a go and how it went? I''d love to hear all about it, and see some pics if you have any (hope you don't mind me asking).

Thanks
Sue

Hi - haven't got round to actually doing it yet. Got bogged down with other things....I have bought some enamels tho'

[joella]

Haha,
Well, good luck with it when you do get time to have a go - cant wait to hear all about it. Good luck with squooshing down your wire to the size you want too!
Sue

[MMM Jewellery]

I think without losing material you can calculate it- 4x4 square has 16 mm cross section, 5x3 has 15 mm cross section so the extra metal must go into the length: 16/15=1.066. So your new wire will be 1.066 times longer. On the other hand, I don't think you will be able to roll it out like that, as Dennis suggests.

[theresa]

Have just finishing forging the 150mm of 4x4. I actually made it 5.5 x 1.7 - it looked better, and it grew to 260mm as well!!
I used a mixture of hammering and rolling.

[MMM Jewellery]

Glad it worked out for you, I thought the initial dimensions would be tricky.
The formula works too: 4x4=16 mm cross section area, going to 5.5x1.7=9.35 mm area; 16/9.35=1.71 fold expansion of length: 150x1.71=256mm new length- for future reference.
Cheers Matt

[theresa]

Thanks Matt - one to remember for next time!