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High-Temp solder for thermocouples

Chrys

#13255

High-Temp solder for thermocouples | 17 December, 1998

Necessity is the mother of invention...

The other day I loaned my last bit of high-temp solder to a co-op and never saw it again. Then I had to run a profile and I was in a pickle with no solder.

So I ran out to the local Radio Shack to see if they stocked something high temp. I was looking for the 88-10-2 stuff I'm used to, but no such luck. Then I saw this "Lead-Free" solder, which is actually 96% tin and 4% silver. It quoted a melting temperature somwehre around 480F, so I figured I'd give it a whirl. Heck, I had nothing to lose at this point.

Well, guess what? This stuff works great! It's got a high enough melting point to run profiles, but it is way easier to work with than the regular high temp stuff. It doesn't freeze as fast when you pull the iron off, so it's easier to get that thermocouple snugged in the joint.

Now I wouldn't recommend making regular solder joints with this, as it seems to have different viscoelastic properties when melted and could easily create disturbed or "cold" joints. It takes a little getting used to. But for thermocouple attachment, I'm sold.

Go figure, Radio Shack.

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Earl Moon

#13256

Re: High-Temp solder for thermocouples | 17 December, 1998

| Necessity is the mother of invention... | | The other day I loaned my last bit of high-temp solder to a co-op and never saw it again. Then I had to run a profile and I was in a pickle with no solder. | | So I ran out to the local Radio Shack to see if they stocked something high temp. I was looking for the 88-10-2 stuff I'm used to, but no such luck. Then I saw this "Lead-Free" solder, which is actually 96% tin and 4% silver. It quoted a melting temperature somwehre around 480F, so I figured I'd give it a whirl. Heck, I had nothing to lose at this point. | | Well, guess what? This stuff works great! It's got a high enough melting point to run profiles, but it is way easier to work with than the regular high temp stuff. It doesn't freeze as fast when you pull the iron off, so it's easier to get that thermocouple snugged in the joint. | | Now I wouldn't recommend making regular solder joints with this, as it seems to have different viscoelastic properties when melted and could easily create disturbed or "cold" joints. It takes a little getting used to. But for thermocouple attachment, I'm sold. | | Go figure, Radio Shack. | Small discoveries by great minds. Nice going Chrys.

For the most part, I've no use for the shack but for just such stuff. I mean, where else can you find it so easily and suprisingly. I sure won't buy much else there as computer stuff or cell phones, but certainly this kind of thing.

The tin melts at low temps but still is tin and, as such, does cause problems with "normal" solder joints. Just keep watching the shack for our next answer to lead free. They should participate on the forum, or do they without our knowing?

Earl Moon

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