Appropriate solder/flux for connecting wire to SS microclips

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Marc_G

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Hi guys,

I finally got around to clipping off the heavily corroded copper plated microclips from my clip whip, with intent to put on some nice stainless ones I got a few months ago.

I forgot to do my research though, and my regular electronics solder/flux doesn't stick to the clips.

Did some googling and found I need more of an acid flux, with some cautions around getting the right kind so residual acid doesn't eat the wire.

What's a good solder to get for this application?

I'll Amazon Prime this thing. How about this:

BernzOmatic SAC300 3 oz. Lead Free, Acid Flux Core Solder

Or do you recommend I buy a paste/flux separately then use my regular solder?

I don't solder much these days... I'm looking for the easy, cheap solution.

Thanks

Marc
 
From Bernzo's web site, it looks like they don't recommend this product for electrical work. They have plumbing solder, electrical solder, and "metal work" solder which is this acid core product.

I've been soldering most of my life, but I've never taken on stainless. The problem is that there is a big risk of flux wicking up the (stranded) wires under the insulation where it is impossible to clean off.

Your best bet is a good, solid crimp connection. But if you must solder, look for products specifically indicated for stainless. I found this page:
https://www.superiorflux.com/stainless_steel_soldering_flux.html

I'd recommend No. 78. No. 79 looks tempting because it's acid free, but that doesn't mean it won't corrode your copper wires or insulation. Try this:

  • Strip the wires a good inch back.
  • Move a 1-1/4 to 1-1/2 inch piece of shrink tubing up the wire past all the exposed metal.
  • Solder on the clip using the No. 78 flux or something similar. By similar I mean both water soluble and limited flow.
  • Wash the residue out. This is why the wires are stripped will up the length.
  • Bring the shrink tube back down and shrink it.
But really, it's better just to crimp.
 
You need to use acid flux. I used it for soldering to steel or whatever on electric guitars. It did not affect electrical connections at all despite what everyone seems to say. Now unless it's microscopic wires used in the electronics industry, then it's a different story.

Acid flux is also useful for soldering copper to nichrome for making your own igniters.
 
Not a single pair of clips was soldered On our old launch equipment. Crimping held up for a year. The clips had to be replaced because the clips filed. The crimp still made a connection.
 
Our club & I have been using Stainless MicroClips for over 10 years.
All stainless steel soldering must use an Acid Flux or nothing well really stick. As the Range Operations & Equipment guy for our club I've done a pictorial "How To" for our club members showing the process i've developed over the last couple years that allows the use of standard 60/40 Solder that has held up longer then the clips themselves:)
Normally stainless products need a silver bearing solder but the method shown below allows our standard solders to hold giving a much more secure connection then Crimping alone. Crimping is the absolute worst method for attaching micro clips Particularly if used on Club "Heavy use" launchers.

View attachment Soldering StainlessSteelClips(Pictorial)-c_09-07-12.pdf
 
Our club & I have been using Stainless MicroClips for over 10 years.
All stainless steel soldering must use an Acid Flux or nothing well really stick. As the Range Operations & Equipment guy for our club I've done a pictorial "How To" for our club members showing the process i've developed over the last couple years that allows the use of standard 60/40 Solder that has held up longer then the clips themselves:)
Normally stainless products need a silver bearing solder but the method shown below allows our standard solders to hold giving a much more secure connection then Crimping alone. Crimping is the absolute worst method for attaching micro clips Particularly if used on Club "Heavy use" launchers.
I'll check out the process and I'll be glad to have learned something new. However, I must rebut some of this.

Just squashing the back end of a clip over the wire is a terrible way to attach it, but that's because it's a terrible job of crimping. I'm an electrical engineer and have spent a large portion of my career designing wire harnesses for satellites, and I can tell you that a properly executed crimp connection is preferred to a solder connection in most applications on satellites, launch vehicles, and airplanes. And that's for connecting silver coated copper wire to gold plated connector pins, where soldering works very, very well. The reason: flux residue corrodes the metal making a crimp more durable and reliable.

As a side note, since lead has been removed from most products, lead-tin allows are no longer "standard" solder; most of the solder you can buy in most stores nowadays is lead free, comprised of 3 to 7 percent silver with the balance tin.
 
I'll check out the process and I'll be glad to have learned something new. However, I must rebut some of this.

Just squashing the back end of a clip over the wire is a terrible way to attach it, but that's because it's a terrible job of crimping. I'm an electrical engineer and have spent a large portion of my career designing wire harnesses for satellites, and I can tell you that a properly executed crimp connection is preferred to a solder connection in most applications on satellites, launch vehicles, and airplanes. And that's for connecting silver coated copper wire to gold plated connector pins, where soldering works very, very well. The reason: flux residue corrodes the metal making a crimp more durable and reliable.

As a side note, since lead has been removed from most products, lead-tin allows are no longer "standard" solder; most of the solder you can buy in most stores nowadays is lead free, comprised of 3 to 7 percent silver with the balance tin.


While I am not an electrical engineer; I agree that with a proper crimping tool crimped connections are perferred for Stationary (fixed) connections. However Micro-clip leads are NOT in any way stationary! the are flexed and stressed constantly. Crimped connections with this flexing serve only to fatigue fracture the wire strands breaking them in pretty short order.

Yes, Flux does corrode the wire in solder connections but if used correctly and cleaned after application the soldered joints on Stranded Copper/Stainless Steel clips have lasted 4-5years in monthly super heavy use.

Not sure were your getting your information about Lead/Tin solders; but if you take the time to look, most major electrical/electronic & industrial supply companys carry a wide range of Lead/Tin and Leadfree/Tin solders. I really like Silver bearing solders but they are so much more expensive the average Joe just doesn't purchase them.
Hope that helps a little.
 
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Why not tin (apply solder to) the clips with whatever flux they require, then clean the flux off. Meanwhile, strip and tin the wires. Now put the (tinned) wires onto the (tinned and cleaned) clips and reflow the solder.
 
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