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Soldering Nichrome wire


mabuse00

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Just curious, did anybody here solve this problem?

 

Google brought some hits, but mostly about american products not available here, and I could not find out what the damn fluxes are made of.

 

 

I tried normal 60/40, lead free with silver, additional zinc chloride flux, no success.

 

There must be something to kill that Chromium oxide, I dont care if the tip suffers too.

There seem to be fluxes for soldering stainless steel, but they state nowhere what's the magic ingredient. Ammonium chloride? Phosphoric acid?

 

PS:

I know crimping is the deal, but I would really like to solder.

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Might I suggest Rubyfluid for nichrome wire? Zinc Chloride is the magic.

 

http://www.amazon.com/Rubyfluid-388-Soldering-Flux-Paste/dp/B0044SD3NU/ref=sr_1_1?ie=UTF8&qid=1424810381&sr=8-1&keywords=Zinc-Chloride+flux

 

Look for killed spirits locally, though once the chromium oxide forms, solder in this fashion to get the chromium oxide to dissolve.

 

http://www.tpub.com/neets/book4/32NE0365.GIF

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Why don't you just wrap it around the two wires? I have never soldered my e-matches. I just wrap the nichrom around one of the connections several times, then do the same with other connection and there is no need to solder. Dip it in H3 with NC and you have a ematch quickly and cheaply.

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Why don't you just wrap it around the two wires? I have never soldered my e-matches. I just wrap the nichrom around one of the connections several times, then do the same with other connection and there is no need to solder. Dip it in H3 with NC and you have a ematch quickly and cheaply.

 

+1, no need for solder.

 

Even better, If you can get hold of some "cat 45" twisted pair copper cables (those old blue ethernet cables - there's about 8 twisted pairs? within) then use some serrated pointy nosed pliers to put grooves into the wire, they are soft copper. It will help to "grab" the nichrome wire as you twist. No solder needed.

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Thank you for your replies.

 

 

I just wrap the nichrom around one of the connections several times, then do the same with other connection and there is no need to solder

Very likely what I'll ultimately do, but I havent given up on soldering yet.

 

 

Zinc chloride alone is NOT sufficient. The stuff called Bakers Fluid contains zinc chloride, ammonium chloride and HCl, I'll make that myself and see what it does...

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I fear you may need to look for old tin/lead solder with a rosin core. The advent of lead free solder started to put a use-by date on simple things like resistors because the component leads tarnished and then the lead free with bioslime for flux just failed to make soldered joints.

 

Having bought plain chips -no compound and no leads it's clear that they are made by winding a spiral of wire round a strip of DS PC board, then chopping into individual units.

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+1, no need for solder.

 

Even better, If you can get hold of some "cat 45" twisted pair copper cables (those old blue ethernet cables - there's about 8 twisted pairs? within) then use some serrated pointy nosed pliers to put grooves into the wire, they are soft copper. It will help to "grab" the nichrome wire as you twist. No solder needed.

 

This is similar to what I do, but I wrap the nichrome first, then gently crimp the nichrome into the copper with some micro serrated pliers. The nichrome as it is harder than copper gets pushed down into the copper and makes a connection that seems to work well for me. If you crimp too hard with the pliers you run the risk of shearing the nichrome if it is a fine gauge, pliers at the wrong angle, ETC. Also if I use "repurposed" multi-conducter copper wire I snip off at least a foot of it to be sure I have a clean copper to work with.

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  • 3 weeks later...

I was told to use phosphoric acid as a flux for nichrome. I haven't tried it yet but the person who told me had good luck with it.

 

Just be careful with such a strong acid and make sure to neutralize it when done soldering.

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  • 2 months later...

 

I use to be an absolute horrible at soldering and I had I don't know how many piece of junk irons. Now and then things would turn out good and I would try the same technique again and it was back to crap. I even thought I was a pro with nichrome then next time I wanted to pull my hair out. The proper solder type and flux is important yes, temperature is even more important. The quality of your iron especially the tip is critical, Look at it this way I must have bought about 5 or piece of jun one k non adjustable irons over the years at $20 to $40.each plus single core solder way too thick for the job and only one Weller throw away had slightly decent tips.

Then one day I came across Dave Jone's EEV blog on you tube and watched a ton of tutorials, lots of great guides, especially for beginners who have no idea why their joints are crap. When I accepted there was only one solution, I dropped a hundo on the Hakko FX-888D solder station ready in about 20 seconds digital adjustable even came with great cutters. Now life is good and so are my solder joints. If you solder at least 2-3 times a year and it's for delicate or expensive applications, even if it's not, bite the bullet and save cash in the long run. It was the best $100 I ever spent.

Just make sure you watch his tutorial and get the gauge solder and learn how how to handle you tips, That's all you will ever need unless your doing a lot of SMD work, or are desoldering hundreds of components, and even in that case I'm sure the FX-888D will be part of the action.

* Note there are other high quality brands like Pace, Weller's Pro Series and others, I just prefer Hakko for several reasons, & that model is excellent!

Anyone can solder given the right materials, even nichrome will be a cake walk

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I just tried. You need to coat the connection with some of those plumber's flux (basically acid flux). Look for something that contains zinc chloride. Home Depot will have it.

 

It makes it possible to solder nichrome to copper with standard solders.

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Zinc flux does help, but its still pain in the ***. Evaporate too quickly and the wire wont wet again etc. Now I just hold down the nichrome wire with connection wire like so and be done with it:

 

post-19767-0-08264400-1433588223_thumb.png

 

Next time I’m going to try crimping or twisting with CAT5. Just have to figure a way that's consistent enough (with PCB I can reproduce 1.5 ohm with +/-0.4ohm accuracy), but it's much work cutting pcb, wetting lead wires, soldering etc.

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I've had great success using phosphoric acid for flux. I do use 60:40 tin/lead solder and a Weller solder station, but when using the H3PO4 for flux, the solder wets the NiCr. Try it and see for yourself.

 

Edit: be sure to use the very smallest amount, so cleanup is easier.

 

WSM B)

Edited by WSM
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That plumbing flux you buy at home depot will work. I tried it and it works great.

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  • 9 months later...
I know it's kind of an old thread but ive had great luck using .063 acid core solder. I get a little tube of it from the local harware store. Made hundreds of e-matches using this with no problems
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Thank you for keeping the tread alive :)

 

I took a longer break from everything and havent soldered a single piece yet, but it's on my todo list, so any valuable information is welcome ;)

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Glad I could help mabuse,

 

I found what I used. Its a 60/40 lead/tin mix .062" general purpose acid core solder from alphametals. I wasn't soldering the nichrome onto bare copper(not sure of your setup). I use .1" headers so they are plated with something (tin I believe) which may have an effect on the solder adhesion. The solders pretty cheap ($5 ish) so it's worth a try in my opinion.

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  • 2 weeks later...

If you are not in the US look in hardware stores or whatever for acid based flux, or at least flux paste designed for stainless steel if you are in an electronic store. Not all countries use copper pipes (in Taiwan it's either steel or PVC, no copper).

 

Anyways acid based flux will solder nichrome easily. You can wire wrap but I have found reliability issues when done this way (half the time it would not go off at all) and soldering is the best way to ensure that this won't happen.

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If you plan on doing a large number of these, try looking for a micro welder on the surplus market. These are very small spot machines, not much bigger than a hot air soldering station, that were used for assembling high reliability electronics (for satellites and such) without solder.

 

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No, I have been using a more expensive version, the 788+ dual pulse spot welder and battery charger to rebuild battery packs and charge them.

 

Do they work? Oh heck yes they work well.

Edited by dagabu
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dag,

that's interesting.

I just checked out a vid on youtube of the 788+ model

 

is it possible to draw a noddy picture of how you might weld ~40g awg nichrome wire onto a piece of thin copper wire ?

I cant quite get my head around the physical arrangement.

 

also why does the current not cause the nichrome to burn through.?

I notice its parallel electrodes, wouldn't top + bottom electrodes be more useful ?...........if so could it be modified ?

 

appreciate anymore info you can provide

did you get yours from china (ebay)

dave

Edited by dave321
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  • 2 weeks later...

dag,

that's interesting.

I just checked out a vid on youtube of the 788+ model

 

is it possible to draw a noddy picture of how you might weld ~40g awg nichrome wire onto a piece of thin copper wire ?

I cant quite get my head around the physical arrangement.

 

also why does the current not cause the nichrome to burn through.?

I notice its parallel electrodes, wouldn't top + bottom electrodes be more useful ?...........if so could it be modified ?

 

appreciate anymore info you can provide

did you get yours from china (ebay)

dave

 

OUCH! Lots of questions...

 

I got mine through Aliexpress for about the same price, $160.00 or so? (Backstory: I worked as a property manager and my guys all used battery powered drills and drivers but dropped them all the time causing the $100.00 battery pack to die so I took one apart and found the ribbon that attached the batteries to each other had come loose. The spot welds were horrible so I took a look online and found the machine. My boss wouldn't pay for the machine so bought it myself and just charged him for the labor to fix the packs. I even rebuilt the packs when a cell died for a fraction of the cost of a new pack.)

 

The 788+ is completely adjustable, the dwell and current are both adjustable so that you can easily spot weld 50ga nichrome wire to a copper wire as long as the copper wire is of a much larger gauge, 22ga?

 

The electrodes are just copper. I have a length of 8ga copper left from my spa install and just chop off a section of it and turn it in my lathe to the desired size and polish the ends.

 

The tricky part of doing a wire to wire spot weld comes when trying to keep them in alignment with the electrodes, for this, I simply used a carpet knife to cut a shallow slot in the end of the electrode that held the nichrome wire.

 

There are clamping spot welders out there too, they seem to have much higher current loads though and cant be dialed down as well (I think).

 

In the end, I found it a lot cheaper In the long run to just buy a 1000 match heads from Nicropulse directly and solder then dip them for custom ematches and just buy the cheap ematches off of ebay for day-to-day use.

 

YMMV

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Would a spot welder work better than using acid flux? I used acid flux and it soldered nichromes very nicely... My only complaint is that I can't seem to secure the wire prior to soldering...

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