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susieq
29-06-2011, 11:00 PM
Is there a formula I can use to work out how much longer and wider silver gets when its rolled out?

I'd like to texture a piece, but with silver the price it is I don't want to buy more than I need, but on the other hand it would be useful to have a little extra in stock so that when I want to have a go at making a couple of bezels for 1mm cabs I had some to hand. 1mm seems to be as good a standard thickness as any to keep a little extra of in stock, so I think I'll bite the bullet and buy a small sheet of this.

However, I was wondering about texturing and thinning in the rolling mill, If I needed a piece that was say .7mm thick, and 10mm x 100mm long, what size of 1mm thick would I need to start off with? Would 7mm x 70mm x 1mm be about right (assuming all edges come out of the rolling mill straight, which of course they won't!)?

Thanks, Susie

caroleallen
30-06-2011, 08:27 AM
I don't think it's possible to say Susie, as it depends on how much pressure you use (ie how much you tighten the rollers). The piece should come out with straight edges unless you're rolling with something very uneven.

Dennis
30-06-2011, 10:33 AM
Hi Susie,
Carole is right, but first of all check on what size silver sheet the flat part of the mill will take. Generally to end up with 0.7mm, I would start with 0.8 and with only moderate pressure I would expect to have about 2.0-3.0mm increase in length and less in width.

If you can texture your sheet on both sides together you will have the benefit of choosing the better side and your sheet will stay almost perfectly flat.

Practice with a base metal first so as to make your efforts more predictable. Most importantly learn how to set the gap between the rollers for consistent results. Copper is good for this.
Regards, Dennis.

ps_bond
24-08-2011, 08:16 AM
Give them enough rope...
Honestly, I'm starting to get to the point where I think banning an entire country from accessing the forum is a good idea.

mizgeorge
24-08-2011, 09:07 AM
Peter, I've done this with several countries on a forum I admin.....

ps_bond
24-08-2011, 10:14 AM
It's an admin option rather than a mod accessible setting, but there's days it is very tempting. It just goes against the grain to tar everyone in a country with the same brush.

Dennis
24-08-2011, 11:36 AM
It just goes against the grain to tar everyone in a country with the same brush.

Yes it's Bitumania. I must admit I haven't quite grasped the appropos of this conversation, or why it arose directly under my last post. Dennis.

mizgeorge
24-08-2011, 11:39 AM
Ah Dennis - you can no longer see the spam post that appeared after you (which is always a problem when moderating). I would imagine the poster originated somewhere in the Far East ;)

medusa
24-08-2011, 12:28 PM
Ah Dennis - you can no longer see the spam post that appeared after you (which is always a problem when moderating). I would imagine the poster originated somewhere in the Far East ;)
heh, I thought I was going mad! Or maybe you and Peter were....

Dennis
24-08-2011, 08:23 PM
Well that's alright then. I don't really like spammers being baited on a forum; it reads too much like witch-hunting to me.

ps_bond
24-08-2011, 09:58 PM
Agreed - it's also far too easy a target. I had warned this one beforehand, but they didn't heed it.

mizgeorge
24-08-2011, 10:20 PM
I see no reason to bait spammers if it improves their lifespan on any forum. There are a couple of boards out there that are particularly bad at removing spam though, and sometimes they need to be pointed out to other, more gullible members.

I'm sorry that Peter seems to be having to deal with these issues all on his own now. Perhaps we could do with another active mod here?

Melanie De Castro Pugh
05-09-2011, 06:53 PM
Regarding the OP rather than the spammery, is a rolling mill the only way to transfer texture into silver from another object? Such as lace, or fabric etc. My only other thought is pmc, but as that's so fiendishly expensive these days, I'm loath to use it :-(

ps_bond
05-09-2011, 07:26 PM
I'm sure I've seen someone using a hammer & a bench block to do something similar, but I can't remember how fine the detail was that they were getting. Anything flexible is likely to move around as it is hit though.

Dennis
05-09-2011, 07:30 PM
Hi Mel,

Here are some other methods of texturing silver sheet that come to mind:

1. Hammering with the round end of a ball-peen hammer. I find the result a bit naff, but if done on a steel block, the reverse side is the more intriguing.
2. Etching with dilute nitric acid. Very versatile for both designs and calligraphy.
3. Making swirly patterns with round burrs which have been slightly bent at the neck while hot, to make them run eccentrically.
4. Making swirly patterns with sandpaper disks on the flex shaft, to imitate the patterns on bistro tables.
5. Using a medium frosting wheel. (eye protection is needed)
6. Using coarse (green) Scotchbrite mops to make swirly patterns with a satiny effect.

That said, even the most humble rolling mill will make endless varieties of texture, using only
remnants of net curtaining, art paper, stencils and textured metals. So this remains my default
method. Dennis.

susieq
05-09-2011, 08:13 PM
On the subject of etching, I have a bangle which I etched for my daughter. Having had my usual numerous tries at soldering before I got it right, it ended up with dreadful firescale. As I couldn't get rid of the firescale by sanding without compromising the etching, I was shown how to heat it up, pickle, wash and pumice several times to get rid of the firescale. I was going to colour the etched part with platinol (need to buy some). Daughter liked the satin effect of the unfinished bangle, and wore it a couple of times even though its not finished off properly yet. She has however, managed to get a few scratches on it, so I want to sand it back to a satin finish again before using the platinol. However, I am a little worried that once I sand it the firescale will show again as I think the re-heating and pickling will just have pushed a layer of fine silver to the surface and the firescale will still be lurking underneath. I guess the alternative is to platinol it first and then sand it back.

If the firescale is obvious afterwards, is there another matt finish I could put on it which would hide the firescale but not compromise the etching? I was thinking maybe one of the texturing brushes for the foredom I am going to get later this month, or maybe the cheaper radial disks?

As an alternative to platinol, which I also haven't got yet, I could use a sharpie to colour the etching, but I'm gussing that the problem with lurking firescale will be the same whichever medium I use to colour it?

Susie

Dennis
05-09-2011, 10:38 PM
Hi SusieQ,

One of the dilemmas in making a piece of jewellery is to know when to stop. Bangles do get scratched in use and it will continue to do so, but you might just get some Platinol now and blacken it all over. Then rub it up lightly with a silver cloth for an antique finish and lightly wax it. Any natural furniture polish will do it

Platinol tends to react very fast and is inclined to leave scaly bits which flake off. To slow it down I dilute a portion with two parts of cold water. Then dip the piece, or brush with a synthetic brush. Also wear gloves. Once an even colour is achieved rinse off in cold water not hot. A slight nuisance is that any exposed solder will show as paler.

Dennis.