Soldering help

[varsity07840]

I don't know what I'm doing wrong, but my success rate stinks. I clean and flux the parts but most times the solder just beads up and won't stick.
I'd really like to get this right. Any help or
steering to the right information would be greatly
appreciated.

Thanks in advance.

 

[Roy]

All depends on what kind of solder and flux you are using. Lightly sand the area to clean it and apply the flux. Some flux does not like a direct flame so you need to heat the piece but do not put the flame directly where you are soldering. Are you using soft solder or silver solder?

 

[Swampman]

I've used this product with good sucess.
[url] http://www.solder-it.com/solderpaste.asp[/url]

 

[bouldersmith]

It sounds to me that you are not getting the pieces hot enough before intoducing the solder. I like 50/50 solder and find that it flows very well with a bit of non corrosive flux, if you get everything hot enough. Try heating the back side of the part and allowing the heat to soak in, this also helps to draw the solder toward the heat creating a better bond. Good luck,
Steve

 

[crockett]

Tell us more, your set up, what you are trying to solder.

 

[madstone]

Soldering requires good clean surfaces and the correct temp to flow. Clean well, flux (use french chalk ( the stuff welders use to mark steel) to prevent solder from flowing onto surfaces not to be soldered)and put the torch flame on the largest part, not where you have your solder! Then as you judge you are approaching the right temp touch and hold the solder to the place you wish to solder. As soon as the temp reaches the right point the solder will flow into the fluxed areas by its own volition (Sumfin' 'bout cap-pil-arry action?). Quickly wipe away any surplus solder and remove the heat. "Beads" can mean too cold or too hot, like baby bear's soup! :winking: Or unclean or unfluxed parts? :thumbsup:

 

[Roy]

Unless ofcourse he was using a good paste flux and a silver solder, then you can apply a direct flame, and then issue would be not having it hot enough. :thumbsup:

 

[davy]

Soldering requires good clean surfaces and the correct temp to flow. Clean well, flux (use french chalk ( the stuff welders use to mark steel) to prevent solder from flowing onto surfaces not to be soldered)and put the torch flame on the largest part, not where you have your solder! Then as you judge you are approaching the right temp touch and hold the solder to the place you wish to solder. As soon as the temp reaches the right point the solder will flow into the fluxed areas by its own volition (Sumfin' 'bout cap-pil-arry action?). Quickly wipe away any surplus solder and remove the heat. "Beads" can mean too cold or too hot, like baby bear's soup! :winking: Or unclean or unfluxed parts? :thumbsup:

Good points! Clean joints are essential!

Remember also you can heat it too much as well, and it will destroy the flux's ability to clean, thus defeating its intended purpose.

Heat the part gradually (not the solder) until the flux flows as water, then check the solder to see if it melts by touching it to the part lightly, once you see it will melt then apply .. but do not overheat!

Let it cool naturally .. do not cool it rapidly with anything .. just let it set until cool to the touch.

BTW if your joint fails for any reason .. be sure to clean the old solder attempt completely to the metal, and then start over again! :thumbsup:

Davy

 

[Zonie]

What the others said, especially the parts about cleaning and do not overheat/underheat the metal.

There is a natural tendency to apply the heat to the solder and not the part. This is the worst thing that can be done because the molten solder will not stick to a cooler part.

Another thing that is very easy to do if one is soldering a thin part to a thick part is to overheat the thin part by applying the heat directly to it or even just close to it.

If your soldering steel, some of the fluxes like rosin or rosin core do not work well, if at all.
IMO, the acid core solders are not much better.
I have had the best results using paste type fluxes.

I've had the best success at creatng good soldered joints by "tinning" both surfaces. This is just a word that means applying solder to a part. It envolves coating both joint surfaces with a thin layer of solder before soldering the parts together.

This is done by cleaning the surface and applying the flux. Heat the part (as directed above) by applying the torch anywhere except on the surface to be tinned. Keep trying the solder on the joint surface area until it starts to melt. Then lightly move the solder around to get the whole joint area covered with a thin layer.
A wire brush is sometimes helpful in getting the solder spread on the surface.
Repeat this with the other part.

With both parts joints tinned, place the two parts together and clamp lightly. Heat the heavy part, again keeping the torch away from the joint area. If the light part is especially thin it won't require any heating at all.
When the proper temperature is reached, a small bead of melted solder will appear around the part joint.
Allow the parts to air cool. Do not try to cool them down with water.

When your finished, don't forget to wash the flux off of the parts. Many fluxes are very agressive and will rust/corrode the parts if not removed completely.

 

[madstone]

Fortunately I was a plumber before I was a gunsmith! The cleanliness of the joint and the quality of the flux and solder outweigh my own incompetence. Heat the biggest part with the torch and only touch the solder to it during hat-up to tell when optimum temp has been reached. Like "baby bears' soup" it can be too hot or too cold.
Biggest problem I have as a gunsmith is folks wanting big gaps filled w solder!!!!!! :thumbsup: