How To Easily Solder Stainless Steel Conductive Thread

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seedpress
 
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How To Easily Solder Stainless Steel Conductive Thread

Post by seedpress »

There is a self-perpetuating myth that it is difficult or impossible to solder stainless steel conductive thread (such as those sold by adafruit). Actually, that thread is quite easy to solder.

Here’s how:
Just use stainless steel soldering flux. I use LA-CO’s “M-A” stainless steel soldering flux, available on Amazon, or many other outlets. (It is seldom available through traditional electronics supply distributors.) It’s not that cheap, but if you can find a 4 oz bottle, it will last you a long time.

Even after you solder the thread, some strain relief is advisable because the joint will be a bit brittle.

For clothing one should use a lead-free, silver solder. If you can tolerate some lead in other, non-wearable projects, then consider trying an eutectic solder, which is a solder alloy that melts and freezes over a very narrow temperature range. Goodbye cold solder joints.

For eutectic solder I use one designated as SN62, which is composed of 62% tin, 36% lead, and 2% silver, with a melting point of 179 C. My pick is Multicore” SN62 0.7mm DLMP22, a solder with excellent embedded flux cores of its own. But without the externally applied stainless steel flux to the conductive thread, that solder just drips off. Add the SS flux and the solder soaks into the thread fast, and then after the iron is removed the joint quickly hardens to a sheen. I get similar results with my lead-free silver solder, though being non-eutectic it doesn't harden as quickly.

Happy tinkering!

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bidrohini
 
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Re: How To Easily Solder Stainless Steel Conductive Thread

Post by bidrohini »

Thanks for the post. Sewing with stainless steel thread is fun. But I always find soldering these threads difficult.

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