Leaded Solder Made in China

[Bazz4CQJ]

Two blobs of solder, bottom strip between P and T; can you spot the difference?

B

[ajgriff]

I suppose the dull surface could be caused by contaminants, insufficient flux or slightly low tip temperature. I opted for 315°C when experimenting with the Jinhu and have used it regularly since without problems.

Alan

[Bazz4CQJ]

Alan, please don't think I'm in any way "having a go" at Chinese solder, I'm just trying to understand more about the 'no-name' product I ended up with.

The board was cleaned with steel wool and then wiped with IPA before use and both solders behaved identically when being applied, up to the point when they froze. It's been suggested to me that it's labelled as leaded, but is actually lead-free. I've never used lead-free, so have nothing to compare to it.

B

[ajgriff]

I've no desire to defend Chinese solder per se B. All I can do is relate my experiences with the Jinhu but like you I'd be pleased to understand what's causing the dulling with your unbranded solder. Aside from the unleaded theory there's the possibility that it's 60/40 lead/tin rather than the other way round. Tin is hugely more expensive than lead! Just a thought.

Alan

[Bazz4CQJ]

It behaves just like Multicore, and is the same over a range of temperatures. Looking at it with a magnifying loupe, it really doesn't look much different from any of my old joints that have dulled with age. It shows a good layer a flux around the joint. I don't have any more ideas about how to assess it further.

It does look, however, that if anyone needs solder and sees genuine Hinhu on sale, it may be worth grabbing it! Mostly, what I was finding, was only very fine gauge Hinhu.

B

[Bazz4CQJ]

Ah, I hadn't compared melting points; turns out the melting point of no-name is a lot higher than Multicore; starts to go mushy at ~230'C, so it looks like it's lead-free?

B

[John M0GLN]

I've just had a quick test with some of my solders, 3 rolls of Jinhu bought over the years, the last in May this year and 2 rolls of Multicore, one of which has Colophony free flux, using an Antex XS25 iron they all seemed to melt and solder the same with no real difference in appearance, the labels on the Multicore reels say 60/40 Sn/Pb but the Jinhu just say 60/40, however looking at the eBay listing for the last one I bought it does say 60/40 Pb/Sn as Alan suggested they could be in #44.

John

[Herald1360]

https://www.vintage-radio.net/forum/...0&postcount=18

[Andy - G8MNM]

Hi,

I just thought I would add my experience with soldering stainless steel. I bought some special liquid flux from China. I had cleaned up the surface of the steel and attempted to solder using unleaded solder, using a Weller soldering iron.
I couldn't get the solder to flow atall, so I tried a larger soldering iron but got the same result.

I then tried rosin cored conventional lead/tin solder with the stainless steel flux and was able to solder quite easily. Seems as though unleaded solder is no good for soldering stainless steel!

I had never come across rust on stainless steel until now. I was patching a small hole in a mudguard.

[G6Tanuki]

Stainless isn't really solderable, as people who have tried using stainless fishing lure wire for tuning drive wire have discovered.

Welding to it is just as problematic (a friend is qualified to welding stainless steel to a standard good enough for nuclear applications.)

[barrymagrec]

It`s not easy soldering stainless but it can be done. I had a saucepan with a broken handle - I spot welded the handle back on but blew a small hole in the pan. I soldered it up using plumbers flux and lead free solder - been good for many years now.

[Bazz4CQJ]

We need to be careful about using the term 'stainless' loosely. I think that the lowest level of Cr which qualifies a steel as stainless is 13%, but British nuclear reactors use quite a lot of stainless which is 25% Cr, though a lot of stainless is 18% (all the '300' series). But as well as compositional variations, there are different structures; austenitic, ferritic and martensitic.

I think that over the years, the problems of welding stainless have been considerably reduced by producing grades with stabilising agents or reducing the carbon content (this helps avoid the problem of "heat affected zones" close to the welds).

There might be info out there somewhere on which grades of stainless will or won't solder, but I don't recall ever seeing it. Can anyone tell me what is the material used for the casing of Li ion batteries? They seem fairly easy to solder to (with conventional tin/lead solder) using the right approach and a good flux.

B