I thought solder used on old radiators whats tin?

[sheepdog]

I went to the junk yard and picked some nuggets off old radiators. Looked like tin, was light like tin, but when I put a little in my 10 pounder it doesn't melt down.

Is there some other solder used to fixed radiators I dont know about?

[Shiloh]

Not that I know of.

Lead/tin or tin/antimony

SHiloh

[smokemjoe]

When I worked at John Deere they used 40-60 solder, I had alot of the soldered joints from lead pipe, I had it analyzed and it came out at.
Lead- 96.3 %
Tin- 1.3 %
Antimony- 2.4 %
This I figured would have alot of tin in, but didnt.

[lwknight]

There area lt of aluminum radiators now days and the solder is an aluminum alloy that melts at lower temperature than the pure aluminum.
Tin is not light. Its heavy. Just not quite as heavy as lead.

[sheepdog]

This was fairly light, lightly golden in color like tin dross. This was for sure steel radiators, from out trucks.

[lwknight]

I would still think that the radiators on trucks are still copper/brass. The solder could be any alloy. might even be part silver. We used silver solder a lot on copper on heater modules for industrial water heaters.
That was many moons ago and alloy technology has advanced a lot since then.

[phishfood]

I would still think that the radiators on trucks are still copper/brass. The solder could be any alloy. might even be part silver. We used silver solder a lot on copper on heater modules for industrial water heaters.
That was many moons ago and alloy technology has advanced a lot since then.

My Mother still owns/operates a radiator shop that my Dad started years ago. We are seeing aluminum cores with plastic tanks on some small dump truck sized trucks now.

The only aluminum radiators that I have seen with other than plastic tanks have aluminum tanks that appear to me to be welded onto the core. We use an epoxy resin in wire form that melts easily with a torch to repair these, so to the best of my knowledge there is no aluminum type solder that might be what the OP is seeing.

Silver solder, more technically a brazing material, could very possibly be what he has, as it sure wouldn't melt at normal lead alloy melting temperatures.

Cheers.

[Snobal]

When I worked in a radiator shop in the early 70's, we mostly used regular solder, but for some jobs we used silver solder that takes lots more heat to melt.

I can't remember now why we used the silver solder, but it costs lots more and was a PITA to work with.

[phishfood]

Higher pressures, higher temperatures, vibration resistance, all are reasons to use silver solder joints instead of regular tin/ lead type solders. Notice that ease of use isn't one of them.

[Jim]

There area lt of aluminum radiators now days and the solder is an aluminum alloy that melts at lower temperature than the pure aluminum.
Tin is not light. Its heavy. Just not quite as heavy as lead.

The weight of tin is 70% of lead.

[cajun shooter]

A lot of shops used 63/37 solder which is great for alloy use. If you do a search you will find that some of it contains a small amount of silver as phishfood said in his answer. Silver solder is used for the uses he stated and I would think that most shops would not have it. My first job after coming home from my tour was in a radiator shop. I pulled and installed all day long and then moved up to doing the rodding and tank painting. Very hot work while breathing all those fumes.