PM Research 4% silver-tin alloy solder and flux.

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wce4

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I'm wondering if anyone on here have or had any problems with PM Research 4% silver-tin alloy solder and flux. on their boilers?
Asking for a friend.

I have personally built PM Research boiler #1 back in 2000 and PM Research boiler #2 in 2008 and to this date they have not failed. (hydrostatic tested each year to a pressure of 120 psi / 8.27371 bar steamed at 50 psi / 3.44738 bar ) # 1 boiler is 23 years old # 2 is 15 years old.

I am concerned because it has been mentioned that solders containing tin lose too much strength at the temperature of steam at 15psi.
 
Although it contains silver this is still soft solder and not silver solder/silver braze , it would not be recommended for boiler construction today.
Depending on local boiler codes it could even fail inspection.
Of course this only applies to steamers used in public and for your own use you can do what you want.
Lets face it Mamods were soldered with tin/lead solder and 1000's have been sold , I have never heard of a disastrous boiler failure.
When I was a kid if I hadn't got any meths I would light a wood fire under my stationary engine boiler , it lasted years.
Dan
 
"Although it contains silver this is still soft solder and not silver solder/silver braze , it would not be recommended for boiler construction today."

If that was the case then why is PM Research still selling it with their boiler kits still today?
https://pmmodelengines.com/solder-flux/I think I will contact them and see what they have to say on this subject. I will post their reply when and if.
Stay tuned.
 
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The Wilesco steam plants were soft soldered.
I found out about soft solder when I was about 5 years old, running my brothers Wilesco plant by myself.

I did not pay attention to the water level, and there was no water gauge.
The boiler ran dry, and the first thing (luckily) that failed was the joint at the steam whistle.
The joint failed, and I distinctly recall the jet of water/steam coming towards my face, and I closed my eyes.

I got some light facial burns, but no loss of eyesight.
Luck was on my side that day for sure.

They really should not allow any boiler to be sold with soft solder (just my opinion).

Sort of like selling foundry furnaces with non-coated ceramic fiber blanket lining (should not be allowed).

.
 
The PM boiler uses the rivited construction for strength of the physical joints and the solder is just to caulk the joints. Rivited and Caulked boilers are not so common these days in UK and Euopean models
 
The PM boiler uses the rivited construction for strength of the physical joints and the solder is just to caulk the joints. Rivited and Caulked boilers are not so common these days in UK and Euopean models
Thank you that make sense. I just sent a email to them asking I will post reply if and when received.
 
Reply from PM Research

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