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hayley
09-11-2013, 06:54 PM
hello, ive got to make a platinum band ring ring next week and have never worked in platinum before im particularity worried about soldering could some one kindly offer me some pointers ? i would like advice on the following -
i use a jewel flame (same as aqua flame) will this give me hot enough temperatures to solder ? what tip size would you recommend ?
can use borax as flux or do i need a special product ?
what type of solder would you recommend ? (easy hard ect) for a single solder on a slim band ring.
do i pickle as normal ?
do i need specialist polishing compounds or can i get away with luxi blue /rouge ?
thank you for taking the time to read this -hayley.

ps_bond
09-11-2013, 07:33 PM
Can't advise on the flame, I'm afraid - I'm using a Little Torch on Pt, with a sharp oxidising flame.
No flux. Doesn't work at those temperatures and you can contaminate the platinum with it.
No solder if you can get away with it - use a sliver of Pt rolled as thin as you can and weld. Note that if you're using sharp corners - eg square wire - then the corners melt first, so in this case you're better with hard solder.
No pickle. It doesn't oxidise and you've no flux residue to remove.
Polishing is a more exacting process - you've got to work through abrasive grades thoroughly before going to polish, otherwise you end up with very shiny scratch marks and nothing more. I've not tried the Luxi on Pt as I'm using some platinum-specific polishes.

There was a really good doc on the AOL site on Pt - can't seem to see it at the moment, I'll post a link if I can spot it.

*DO* wear appropriate welding glasses, the emitted UV can be quite a lot. Also, pretty much everything used in normal soldering will break down at those temperatures - binding wire will contaminate the metal, soldering blocks will turn to slag etc. etc.

It's different, but really satisfying to work with :)

hayley
09-11-2013, 09:17 PM
thank you for getting back to me im still a little bit confused, sorry ,
i want to join a 2.3mm d-band i guess it has 2 straight edges would you recomend welding or soldering ?
do i need more heat to weld rather than solder ?
will welding leave me with gaps /marks in the join?
my jewel flame has a sharp oxidizing flame and should go up to 1800 deg c -will this be enough to both weld and solder ?
what am i doing with the tiny sliver of pt ? do i lay it over the join and it melts into the join or do i feed into the hot ring with tweezers ? (sorry if this sounds daft, im not familiar with welding )

ps_bond
10-11-2013, 09:20 AM
You might get away with welding it, if you focus the heat on the centre of the D. Otherwise, hard Pt solder.
The difference in melting points is around 200C, check the datasheets! Pt melts at 1768C for pure Pt, alloys will be different. Your torch might not have enough oomph for welding, I'm not sure - the Little Torch can theoretically hit 2600C with propane.
Welding should leave no visible join - you're using the same filler as the parent metal, so it ends up as a solid piece. You put the filler piece between the joint, then heat the thing - with rings you use the tension on the ring to clamp it in place.

Oh, and use tungsten tweezers if you're using them...

Of course, a laser welder is an even better solution :D

SteveLAO
11-11-2013, 11:44 AM
If you would like to PM me I will email you an extremely comprehensive pdf that we put together with Johnson Matthey concerning everything you need to know about working with platinum. I think you will find it really helpful...

ps_bond
11-11-2013, 02:19 PM
That's the doc I couldn't find in the downloads section - and yes, it is very, very helpful. Extremely comprehensive, as you say.