Silver Solder & Boiler Making – Australia

[Nick Campitelli 1Participant @nickcampitelli1]

I am about to make my first Eric G1 boiler and am a little confused by the solder types. The Australian Miniature Boiler codes list A2, A3, A4, A6, A7, A410 as allowable alloys, yet when I went to my local CIG shop with the code, I was sold A19 Prosilver 45T which is 45% silver (cadmium free) and which they were adamant still compliant. Is this ok to use?

Specs straight from the CIG website are as follows:

BOC ProSilver 45T Cd Free Brazing Alloy

The Prosilver 45T alloy was developed as the cadmium free replacement for ProSilver 45. It is suitable for carbon and low alloy steels, copper and copper alloys (aluminium bronzes with more than 2% aluminium require special flux), nickel and nickel alloys, and stainless steels for food and medical applications (not exposed to continuous contact with water).

• Suitable for continuous service operating temperatures up to 200°C.
• Used widely in marine applications due to its resistance to dezincification.
• Good corrosion resistance.
• Low brazing temperature, coupled with a narrow melting range, makes it free flowing and produces joints with small, smooth fillets.

Brand:	BOC
Standard:	AS/NZS 1167.1
Classification:	A19
Consumable Type:	ProSilver 45T

[Nick Campitelli 1Participant @nickcampitelli1]

Silver Solder Types

[Paul LousickParticipant @paullousick59116]

Hi Nick,

I am building a welded steel boiler and am not familiar with silver soldering copper. Ask the question on http://www.tractiontalkforum.com in the model section. There are a couple of people from Oz who are building copper boilers. They should know what to use.

Paul.

Edited By Paul Lousick on 03/04/2015 07:32:30

[andrew winksParticipant @andrewwinks64215]

Hi Nick, contact SBA Amalgamated in Bayswater, Vic for 45% silver braze rod, they sell to the model engineering guys. If you are building a reasonably sized copper boiler, say a 5" gauge, buy a half a kg as you need a fair bit of that and you will some left over for all the other fabrication. Price varies depending on the latest silver prices. They were still supplying rods with cadmium so make sure you are aware of the exposure risks. I've also used the BOC product, seems ok and I've just had my boiler pass the hydrostatic test.

Make sure you get a copy of the Aust boiler code for copper boilers and no need to tell you that clean bright surfaces prior to brazing are a must.

its a lot of fun and almost a black art when compared to the precision machining of the motion work.

Cheers, Andrew

[Nick Campitelli 1Participant @nickcampitelli1]

Thanks Andrew, good to know that you used the same older with no probs. For now I'm only making gauge 1 boilers but I may make a Rob Roy or Minnie Traction engine in the near future.

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