Best kind of solder for a Poor Man's foldback

[49bv]

I'm currently trying to install fold back on my M3 and I'm having a tough time to get my solder to "stick" to the terminals. I am using Bernzomatic silver bearing rosin core solder. Was wondering if anyone could chime in about this.

[KC9UDX]

Eutectic lead bearing rosin-core solder, I expect. 63/37.

Make sure you have enough heat for enough time.

Silver solder takes too much heat for these kinds of things unless specifically called for (ceramic strips are one such case).

[Jaim]

I've done several foldback mods. The first thing I do is remove excess solder on the terminals to expose the "ears". That makes it easier to hook the resistance wires to the terminal. Next I clean with flux remover.
After that I cheat - Hakko soldering station and 60/40 solder.

Jim

[KC9UDX]

Almost nobody should use 60/40 these days. Eutectic 63/37 is affordable and obtainable enough.

Especially anyone who isn't a soldering expert should use eutectic solder. It eliminates cold solder joints, which to most people look good and normal, but will cause many headaches!

[bourniplus]

Hi, I don't want to hijack the thread but while we're on the subject, can you guys with more experience than me comment on cheap soldering irons vs. more expensive ones? Recently, my soldering iron that I had paid 10$ twenty years ago died. I figured it did its job pretty well in all those years, so I got another cheap one but I'm still considering getting a fancier one. My main use is maintainance on my Hammonds/Leslies and maybe some other small electronics projects. I'd like to have others' opinion about this. Would adjustable temperature be a big improvement?
Also, I'd never heard of eutectic solder, I'l have to look into that.

[David Anderson]

Once you've worked with something like a Hakko or Weller temperature-controlled soldering station, you will wonder why on earth you ever put up with using a cheap pencil iron. In particular, I see lots of damage done by people trying to use an iron that can't deliver enough heat. They sit there trying to melt an old joint and do all kinds of heat damage to everything around it. With a temperature-controlled iron that can respond to the demand, you can solder wires without melting the insulation.

Like KC9UDX, I use 63/37 solder, Kester brand.

[Goff]

For silver and I don't blame one for using it, you need proper heat. If your iron is too low wattage, dirty, you will have to spend more time heating up the pieces for the solder to melt.

Always clean the tip with a steel/brass wool and don't let the solder burn up on the tip.


Although I would like a nice solder station, I have found success with these inexpensive solder pencils.



But this will not work for all soldering, sometimes you need a 100 watt iron to get solder to melt onto brass plates.

[tiredoldgeezer]

For Hammond TG and Manual wiring, a $10 soldering iron is fine and dandy and I've soldered jillions with one. I've used a pistol gun, too. Hammond lugs are the most ordinary soldering there is. I HAVE a $200 station complete with SMT tech, but I also have a bargain basement soldering pencil and it works fine on Hammond stuff.

BUT - gotta have a smooth, tinned tip. Maybe you should have a file to occasionally dress and smooth the tip. You gotta give it time to preheat properly. You should have at least a sponge but that brass brillo thing works even better. Whatever it takes to keep the tip shiny. Certainly good practice (tinning and cleaning) is more important than configuration or brand name in this particular application.

And most of all, you need a solder-sucker. Get the big goofy blue plastic model. I have one that's many years old and it still works.
You need the solder-sucker because there is no chance you're the first iron in there. To disconnect, generally, you can just heat the joint and pull the wire. But to connect, you generally need to heat; suck the solder off in usually a big drop, exposing a shiny lug; then put the wire(s) through the hole and add fresh solder.

No amount of old solder holds and flows as well as fresh solder. Never be shy about removing old solder.

TOG

[KC9UDX]

If you get a plated tip, you never have to do anything to it. I resisted using them for decades, but like David says about temperature control, this is a luxury you won't forego once you've used one.

I also recommend a Soldapult style solder sucker. The genuine Soldapult is the best choice and is not much more expensive than the cheapies. But the Radio Shack one and the ones that look like it, work too.

[tiredoldgeezer]

If you get a plated tip, you never have to do anything to it. I resisted using them for decades, but like David says about temperature control, this is a luxury you won't forego once you've used one.

I must be worse than i think. I've never had the luck with plated tips i have with tinned copper and I don't know why. Maybe plated tips come with temp control and I don't know the right temps to set it at. Can't ever get the solder to 'act right' unless the plated tip is almost glowing red. I dunno. Old Dog/ New Tricks. Just don't know.

Now for little leads on components, yes, it seems to work. But for big lugs? I'm still living in the past, I guess.

[KC9UDX]

There seems to be different plating used. I don't actually know what the plating is.
What I know is that I've had many Radio Shack branded irons that had some kind of plating that would come off over time.
I've had Weller brand irons with tips that seem to have indestructible plating. I haven't sanded any but otherwise they always look new.
I suspect you are using the former kind.

My little Weller pencil iron tip works as well as my biggest old Weller gun for these kind of lugs. I think you might not have as much heat as you think you do. I don't know what else to tell you. What kind of iron are you using?

[tiredoldgeezer]

What kind of iron are you using?

My usual rig is a Weller EC1000. The knob goes from 350F-850F; I get my best results around 475. Dunno if that's the right setting and who knows how accurate the knob is.

My 'nicer' rig is a Chinese X-Tronic 4000. Digital readout. Iron and air. 392F-896F. Usually around 600.

Both of those use plated interchangeable tips, though not with each other. The old Weller uses the old short tips and the X-Tronic uses the long-sleeve insert tips.

My pistol grips are also Weller with the 2 stage triggers. A big one that I seldom use except on wire-to-metal joints, a D550 240/325W. A 'regular' sized Weller 8200 that I use on a lotta Hammond and other general stuff; 100/120W.

And, of course, a couple of generic pencil irons. I keep those around simply because they're so easy to use if a guy has to string a long extension out from the bench or into the garage.

Anyway, anything you can tell me, I'd be glad to learn. The plated tips are and have been a pain including brand new ones. Solder don't flow so great. Even old private stash lead stuff.

[KC9UDX]

It sounds like there is nothing wrong with your irons. Before I even read your last sentence, I wondered if you were using old solder, or maybe some hardware-store brand lead-free stuff.

Have you tried new lead-bearing solder? Kester is always good, but even the Amazon bait-and-switch Chinese imitation stuff seems okay. I recommend Kester 2463370039. https://www.digikey.com/product-deta...E1101-ND/31099

I don't know if you can purchase it in smaller amounts. But really, it's hard to go wrong with that solder. Kester 44 is very easy whetting, and seems to last forever. This particular one is eutectic, which is very forgiving but not compromising. It's .031" which will work for most jobs, but perhaps you have a different gauge preference.

I have a large stash of solder acquired over the years, some that goes back to the early days of radio. I use to use it, but I've used up all the good stuff and the rest just doesn't work so well anymore. I only use it now for mechanical stuff, or for big desoldering jobs.

[tiredoldgeezer]

Then maybe I oughta throw that down as a serious question.

Does solder get old?

I know soldering sometimes gets old, but does solder? I've seen lead solder with a little white powder in it (lead oxide, i presume) but it still worked fine.
Does the resin core evaporate? or seep through? Will old solder only work with supplemental flux?

Because I woulda never suspected such a thing. I got solder from all ages. Some of it older than me.

[KC9UDX]

I didn't think it did either, and that's why like you I have some ancient stuff (most of which did work well even if it smelled different, at one point). I had read somewhere that it does go bad, and I had read about other people having it go bad in years, not decades. Frankly I don't recall what the method of aging is. But after reading that I bought some new solder and found it to work much better.

i think the rosin goes bad, not necessarily the alloy, but bad rosin probably reacts with the alloy too, I expect.

I think you'll be pleasantly surprised at how well new solder works.