Stub Mandrel | 19/06/2012 19:26:54 |
![]() 4318 forum posts 291 photos 1 articles | Any advice on this? It's a standard gent's ring so it's fairly wide and not a high carat (18?) alloy. I can easily make an expanding mandrel on a slow taper and squeeze it in a vice, but do I need to anneal teh ring and are there any gotchas? Neil |
JasonB | 19/06/2012 19:32:46 |
![]() 25215 forum posts 3105 photos 1 articles | RDG do a ring stretcher, have a look at that to get some ideas how to make one, looks like it stretches the metal between two rollers. "Its under their new lines to RDG section" J |
David Clark 1 | 19/06/2012 19:37:19 |
![]() 3357 forum posts 112 photos 10 articles | Hi There As its a gents ring, there is no point telling the bride to go on a diet. I would try a rod through the centre of the ring and roll the rod back and forth along a piece of hardwood or similar. This might stretch the ring sufficiently. regards David |
David Littlewood | 19/06/2012 19:51:15 |
533 forum posts | Neil, This site shows the various tools which jewellers use for this, and a few useful comments about how much you can expand a ring without damage: No doubt a further search among jewellers' suppliers will turn up more. David |
Stub Mandrel | 19/06/2012 20:30:22 |
![]() 4318 forum posts 291 photos 1 articles | Thanks for the ideas. I hadn't thought of rolling it. You've given me a few ideas, but can you anneal 'gold' (as in gold/copper alloy). Edit: it seems that for 9/10k gold (which I think it is) just red hot, then a rapid quench, otherwise it gets brittle. Another suggestion is put on a shallow taper and hit it with a hide mallet. Neil Edited By Stub Mandrel on 19/06/2012 20:43:08 |
V8Eng | 19/06/2012 21:17:19 |
1826 forum posts 1 photos | Hi.
If there are any colleges or craft centres teaching jewellery in your area they will have the equipment, and may be able to help.
Edited By V8Eng on 19/06/2012 21:19:21 |
Peter E | 19/06/2012 21:21:22 |
48 forum posts 22 photos | I have done precisely that some years ago. I used a slow taper Ring Mandrel like the round ring mandrel in David L´s post above. Slip the ring on to the mandrel and using a plastic hammer (no metal at any cost) gently tap the ring on the mandrel. The gold (typically 18 carat) is very soft so it will start to creep up the mandrel almost for every blow. You can actually feel it because the ring should be gently held tight to the mandrel while tapping. After a few blows you get the idea. BR /Peter
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Stub Mandrel | 22/06/2012 21:35:29 |
![]() 4318 forum posts 291 photos 1 articles |
For reasons of durability and impecunity when i got married, i thik its more likely to be 9 or 10K gold
Even so, I tried a nylon mallet on it, without annealing, over a bar that was a loose fit inside it. It's hard to be precise as it wasn#'t perfectly round, but I appear to have opened it up a little, but has helped a bit - say the difference betwen a force fit and a push fit When I can find my elusive tub of easyflo flux, I will try annealing it and have nother go -I think I need at least 1/32", maybe more. Neil |
AndyP | 23/06/2012 00:15:17 |
189 forum posts 30 photos | Only just seen this question and it is what I do ! Yes anneal, as described by John above, your usual flux will do fine. A good rule of thumb is to anneal for every two sizes growth of the ring, a UK size is roughly 1mm on circumference. You should be able to take a plain 9k band up several sizes with a slow tapered mandrel and a rubber or nylon or hide hammer, since you don't need the whole range of sizes on the mandrel turning one becomes quick and easy, I have made several for specific jobs. If it is a wide band, say 6mm or above, then keep reversing it on the mandrel so both sides end up the same size. I like to do this job in front of the customer and dispel the myth that what jewellers do is difficult and therefore expensive.
Take Care |
Springbok | 23/06/2012 03:15:45 |
![]() 879 forum posts 34 photos | Hi Stub yes listen to andy Take it to you local jewell's shop they will have all the kit to do this for you. Items like this should not be messed around with if they have great sentimental value. take it to the profesionals. Bob Edited By Springbok on 23/06/2012 03:19:38 |
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