Silver Soldering Query

jamoor · 15 Nov 2008 at 11:20

I am looking to do some silver soldering with brazing flux, essentially all I need is a blow torch.

I believe this would be possible with propane, the question is do I need to have both propane and an oxygen tank?

JBuk · 15 Nov 2008 at 11:51

I think you do iirc

J1234 · 15 Nov 2008 at 11:56

Mapp gas and oxygen yeah.

Dandle · 15 Nov 2008 at 11:57

The torch needs to be hot but you may well find something like map gas will get it up to the right temp. How much are you doing? enough for a little blow torch or are you going to need bigger bottles?

danza · 15 Nov 2008 at 12:32

You will not necessarily need an oxygen tank. All the silver soldering I do (smallish stuff, say 1" dia by 3" long) uses butane only. A good flux is Tenacity No.5, but as the name suggests, the resultant residue is ridiculously difficult to remove. Even wire brushing won't get rid of it.

jamoor · 15 Nov 2008 at 15:42

It will be fairly small stuff, I was told to get those big, tall tanks?

danza · 15 Nov 2008 at 17:24

jamoor said:
It will be fairly small stuff, I was told to get those big, tall tanks?

If it is small, then you should really be fine with a single gas. Propane or butane should be fine (nigh on exactly the same burn temperature in air).

Are you doing much soldering? Have you silver soldered before? I've been doing it on and off for the last 7 years or so, and I still balls it up occasionally.

jamoor · 15 Nov 2008 at 20:05

danza said:
If it is small, then you should really be fine with a single gas. Propane or butane should be fine (nigh on exactly the same burn temperature in air).

Are you doing much soldering? Have you silver soldered before? I've been doing it on and off for the last 7 years or so, and I still balls it up occasionally.

not really, never done it before, as anything it comes with practice.

Bill101 · 15 Nov 2008 at 20:18

jamoor said:
not really, never done it before, as anything it comes with practice.

Am I the only one who will be watching the BBC news for an unexplained explosion in Nottingham?

danza · 15 Nov 2008 at 22:56

jamoor said:
not really, never done it before, as anything it comes with practice.

Indeed it does.

I find that using Tenacity No. 5, a liberal application to the joint being made (both parts), a lot of heat (component orange to red) and just dribbling the solder around the joint does the job.

Filing grooves around the joint can increase strength and allows the solder to flow more readily into otherwise more 'restricted' areas of the workpiece.

Just make sure the components you're soldering are properly degreased, and you should be fine.