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soldering help

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soldering help

Old 11-15-2017, 05:59 PM
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Default soldering help

I am currently building a set of floats for my 9ft Taylor Craft. I built a set of floats for my Piper Cub last year but had some issues with cold solder joints. I soldered the frame for the Cub using propane and silver solder. We have a Tig welder at work and I thought I would bring the detatched part of the landing gear and have it Tig welded. Well, it did not quite go as planned. The wire is 3/16 in diameter and nearly melted in half! My friend who did the welding lowered the voltage but it really cooked the metal. I thought I might Tig weld the Tayloy Craft frame but after seeing this I quickly decided to go back to soldering. The problem is my soldering iron is only 60 watts, and I need at least 150. I was told that because my iron is so low wattage there was a greater chance for a cold solder joint. I soldered the frame for the cub using propane but found it very difficult to have consistant heat at just the right temperature. I watched a youtube vidio of someone soldering landing gear usind a 175w soldering iron which appeared to distribute heat in a much more efficiant manner. I have looked all over and where the heck can I get a 150w or better soldering iron?? I looked on the internet and did find some. I would like to deal in person, with a store, and not online. And one more question. What kind of paint can I use that would resist the corrosive affects of glowfuel. The cowel on my cub is starting to look terrible. Help with these matters will be greatly appreciated.
Old 11-15-2017, 08:30 PM
Leroy Gardner
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Left seat I use a micro torch that burns butane for all my soldering when using 2% silver bearing solder. If you copper wire wrap your joints the torch and solder will do a great job, I have a 150 watt iron that takes forever to heat and is a PITB to use. Some of those solder stations are suppose to work well for these things. Personally unless your going to do a lot of it it's a waste of money when a micro torch will do it all and it's not expensive.

2 part urethane acrylic enamel is about the only type paint that's fuel proof to nitro, you can use the clear to cover most paints.

Old 11-16-2017, 02:24 AM
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Big box stores like Home carry Weller soldering guns. Mine (a Weller D550) can be operated at either 200W or 260W depending on how one depresses the trigger. They also make ones that operate at 100W/140W.
Old 11-16-2017, 06:57 AM
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You can't beat Harbor freight for prices but I agree with Leroy Gardner, use a micro torch. Any electric soldering iron will lose heat as soon as you touch the item you are soldering especially if it has a large amount of metal like landing gear. And butane is hotter than propane.
Cold solder joints are typically caused by heating the solder, not the item being soldered. Heat the item to red hot, then touch to solder to it and let it melt the solder.
Old 11-16-2017, 08:18 AM
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Living in Bra,pton, there are all sorts of places where you can get what you want without going on-line, whether it's a higher powered electric soldering iron or a torch. You can also get a soldering attachment for torches.

Try Princess Auto, Crappy Tire, Home Depot, Home Hardware, Lowes or any other large hardware store.

Before you attack the actual landing gear, it's a good idea to practice to learn how to do it well.

Bind the joints with fine wire first. Sig makes an excellent copper wire for that use. And some flux usually helps. Also remember, as already stated by rgburrill, that you heat the parts to be soldered to sufficient temperature that the solder melts when in contact with them. Don't touch or move the parts until the joint cools. If you are using silver solder you want to get it right. Taking that apart uses higher heat and can be a real P.I.T.A.
Old 11-16-2017, 12:16 PM
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Hi left seat, I thought a picture of what I use to solder piano wire gear or mounts made from it would help.

Bernzomatic torch comes with a solder tip also, I use and enjoy mine a lot. Stay-Bright soldering kit will solder a lot of stuff and make a solid solder joint on brass & steel metals. I use Bernsomatic water soluble flux for it's easy water clean up after the solder joints are cooled, the liquid flux really works well and all flux is a corrosive so needs to be cleaned off as best as possible, steel will rust as well. Hot soapy water and a small wire brush will clean most of it off.

Some practice using this will go a long way, don't apply the solder until the metal is hot enough to melt it then remove the heat, allow to cool before handling your work.

Hope this helps
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Last edited by Leroy Gardner; 11-16-2017 at 12:18 PM.
Old 11-16-2017, 03:23 PM
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Originally Posted by rgburrill View Post
You can't beat Harbor freight for prices but I agree with Leroy Gardner, use a micro torch. Any electric soldering iron will lose heat as soon as you touch the item you are soldering especially if it has a large amount of metal like landing gear. And butane is hotter than propane.
Cold solder joints are typically caused by heating the solder, not the item being soldered. Heat the item to red hot, then touch to solder to it and let it melt the solder.
To much heat is as bad as not enough. Red hot is far far to hot to make a good solder joint. You do need a good soldering iron for soldering 3/16 diameter or larger wire. There are two things you need for a good joint; cleanliness and adequate heat. It is always a good idea to use an acid flux with this type of solder. Just remember that, when done, again really clean the soldered area well. Scrub using a solution of water and soda helps immensely when you use an acid flux as this neutralizes the acid residue and prevents the rust that is sure to occur if you leave any acid residue on the part. Use an iron with lots of mass (a big heavy head) so that you do not loose heat when you start the soldering process. The most important part is to make sure everything is clean, clean, clean before starting the soldering process. If you have the proper mass for the soldering head, anything more than 100 watts should do a good soldering job. I agree that properly used a butane torch will do a good job but it takes a lot of skill to not overheat the wire causing it to lose all temper or burn off the flux making a poor joint. Even then, using a good acid flux makes the ability to make a good solder joint easier.
Old 11-17-2017, 12:35 PM
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I'm glad to see some people know to use flux. For doing electrical work, a rosin flux cored solder is great but, when dealing with heavier stuff, a true flux can't be beat in getting solder to stick. I have used silver solders that claim flux isn't needed, only to have the joint fail. Something you can also do, in a pinch, is to use brake cleaner to clean the parts being soldered together. It does work but not as well as true flux
Old 11-17-2017, 02:55 PM
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Use liquid cleaners to remove oil/grease from the joint area but. sanding or a stainless wire brush work best to prep the joint be it for soldering or welding. Steel wool can be used but it cannot have any additives that keep the wool from rusting. I have used the 2 inch Scotch Bright pads and a air tool.

Soldering solid wire I wrap the wire together using 19 gauge steel mechanics wire. Sand the solid wire in the area to be joined then sand a length of the steel wire then wrap. The nice thing is that wrapping it with the steel wire will hold the whole thing in place and allow you to adjust everything before soldering. Don't leave it to long even overnight can start the oxidation process affecting the solder job. A few drops of acid flux and solder.

Its not so much the wattage of the soldering iron as the mass of the heated tip. An 80 watt is plenty for even 1/4 wire if the tip is large enough to hold the heat throughout the soldering job. A 200 watt soldering gun is a poor choice if the heat is wicked away once the solder begins to flow and the solder job ends up incomplete and results in a cold joint. First three pictures, first the two pieces of wire to be joined and the steel wire wrap and heavy duty soldering iron. Second the 1/4 inch wire and steel wrapping all sanded and ready to go. Third the joint wrapped ready for solder.

Last three are the float gear for my Piper Pawnee. Little lighter wire all around. You must size your wire to the job and make sure the solder tins the heavy wire not just the wire wrapping. The joint needs solder right through it.
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Old 11-19-2017, 02:11 PM
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Soldering, brazing, welding, getting two pieces to stick together. Clean, clean, and if you think it is clean, well clean it again.

The material you are using plays a big part in what you use to stick it together. I have irons from a micro pencil tip to a 120 watt stained glass iron, I have (3) micro torches that run on Butane, (2) gas torch sets and the small Burnzomatic Mapp gas oxy torch

Each has its best use and some you can get by with. I am also a tool junkie

I had to do some 5/16" piano wire. I tried my electronic solder, it was right there not good. It would not stick. So I grabbed the acid flux, 1/8 diameter 70/30 solder. It was sort of OK. I was using an 80 watt iron. I switched to the burnz and brazing rod. Much much better. Only issue I have with the set is those cans are not cheap and they do not last that long.

I might have had better luck if I would have used the micro torches. The solder just would not flow, if I took the iron across it, it would flow, but it seemed the heat just did not penetrate that far. When I used the torch, you could see the brass flow to the other side and fill the area between the wires.

The surface area of the irons tip plays a big part in how it give up the heat. Of you have the pencil point, there is not much area to send heat into the material. You can add to the area by letting a puddle of solder form and that will help send the heat into the part. On the bigger iron, they have the chisel tips with a big flat area to send the heat.

Here is the burnz torch set. Took me a couple of bottles to figure out to use it.

I bought a set from HF when they were $99.99, but it did not come with the tanks.

Depending how much a set of small tanks costs, would make simple work out of brazing 3/16 wrapped wire. Actually, would be over kill. But I have used it for other things so it has paid for it self in reduced frustration.

I have the older version, mine is orange. I must have gone through 5 or 6 of the butane bottles with this. Best heat shrink shrinker I have used.

I once had the bright idea I would mig weld the 1/4' Piano wire. I turned it down as low as it would go. Lowest heat setting, lowest wire feed speed. It would blow through if I held it for more then .00000000003 second. You would need to be a lot better welder than I am. I am sure it could be done, but not at my skill level.

Old 11-22-2017, 11:13 AM
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Piano wire is easiest soldered together using a simple soldering iron.
For more then 40 years I have been using a 50W Weller soldering iron and it is capable of soldering even 5mm piano wire with ease. The best soldering tin available is "stay-Brite". Stay-Brite is a silver/tin solder and has a flux that makes soldering very easy as you don't have to clean the surface you are about to solder,othervise a thorough cleaning with sandpapper is necessary. You should never heat pianowire red hot as this removes the springiness. This means using Tig or Mag welding as well as old style acetyle torch as not suitable metods to join pianowire.
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Last edited by jaka; 11-22-2017 at 11:18 AM.
Old 11-23-2017, 03:57 PM
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I've done this using the burner on my gas stove at home. If others can do it with a soldering iron I'm impressed, because I never figured it out. I've used a propane plumbing torch also. With both heat methods, I used standard plumbing solder and flux. I hear Stay Brite is better, but regular plumbing solder works just fine too.
Old 11-24-2017, 08:11 AM
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Jester, how do you get away with using the stove, sneak in the house when the wife is not home? I always use either a propane torch or a butane torch. As long as you have enough heat to get all of the metal hot enough to melt the solder you are fine.

Old 11-24-2017, 08:30 AM
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Yep, she works later than me sometimes.
And you're right, people overcomplicate this stuff. The metal doesn't care how you heat it as long as it gets hot enough. Temperature control is a little harder with the stove or a plumbing torch, but it's doable. All that's really required is to heat the metal until the flux bubbles and put the solder to it. If the heat is right, the solder will flow to the hottest area and wick itself into all the crevices. It's not rocket science.
Old 03-30-2020, 09:15 AM
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This is a very difficult situation, you need to see it all with your own eyes. You definitely need the help of a specialist or experienced welder. I have not encountered such a situation, of course, but once I broke the frame of my bike. I was very upset because this bike was given to me and it is very dear to me. I was not confused and decided to fix it myself. Fortunately, I came across an excellent guide to metal welding at prowelderguide.com and I managed to weld the frame myself. In addition to this, I did it so well that it became very firm as if it had never broken. This guide may help you as well

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