QA

Quick Answer: How To Solder Copper

What kind of solder do you use on copper?

Types of Solder Buy lead-free solder that’s designed for copper water pipes; you’ll find it in the plumbing section of the store. Solder with lead is still available, but the lead can leach into your water supply, so don’t use it.

Can you solder copper without flux?

Flux is a chemical which helps you solder. Flux prevents the copper from oxidizing as you heat the copper with the torch. You can solder without flux, but it is really difficult! Flux is applied to both the pipe and the fitting with a handy miniature paint brush.

Can you solder copper to copper?

Copper pipes and other copper parts can be soldered using various metals with low melting points. Traditionally, lead alloys have been used for soldering copper, but these have fallen from favor in recent years due to lead poisoning concerns. Today, copper water pipes are soldered with lead-free flux and silver alloys.

Can you overheat copper pipe when soldering?

Overheating is a major problem when brazing or soldering copper pipe because the flux will burn (become oxidized), stop working, and become a barrier to tinning. In addition, a heavy oxide can be formed on the pipe itself, preventing a bond from forming between the filler metal and the pipe surface.

Do you need flux to solder?

Yes, solder can be used without flux. To do so, you will need something other than flux to break down the oxides on the metal surface, without which your surface may be damaged or not properly cleaned.

Why does my solder not stick?

A classic reason solder won’t stick to something is because you’re not getting it hot enough. My interns come to me with this problem all the time. Make sure the tip of the iron is nice and shiny. Touch some solder on it, and it should melt almost instantly.

Can you use too much flux when soldering?

Although there is a sufficient amount of flux present in the core of the solder wire to get your job done, the technicians (to make their job easy) tend to use additional flux in form of paste or liquid during the rework on the PCB. There is no problem with the use of flux during soldering.

What is the purpose of flux when soldering copper?

The main purpose of the flux is to prepare the metal surfaces for soldering by cleaning and removing any oxides and impurities. Oxides are formed when metal is exposed to air and may prevent the formation of good solder joints.

Can you solder copper with propane torch?

Torch. The torch needed for soldering copper can be propane or MAPP gas (methylacetylene-propadiene propane). Propane works fine, it just takes longer—which may work to your advantage if you are new to soldering copper and are working on 3/4-inch or 1/2-inch pipe. The choice of a torch is really up to you.

Can I braze copper with a propane torch?

Here is the answer to whether you can braze with a propane / air torch. You can but you have to control the environment so that the heat loss to the atmosphere and parts is lower than the heat being put into the braze joint. It is a standard braze alloy that melts over a range of 1250 – 1305 F.

How do you bond copper to copper?

Copper is a highly-conductive, corrosion resistant and ductile metal which is easily bonded by acrylics or epoxy resins. Superglue (cyanoacrylate) glue, can be used to glue copper, however, it would not be the first choice.

How long should I wait to turn water on after soldering?

Step 4: Testing the Solder Joint The only good way to test is to put pressure on the joint (turn on the water to the house). Be sure to wait until the solder has cooled (2-3 minutes) before pressurizing the line to avoid the solder cracking due to a quick change in temperature.

How long can you leave flux before soldering?

This is why it is important to flush the lines when not using water soluble fluxes. Wipe excess flux off the exterior of the pipe after solder joint has been completed, and never wait more than 4 hours to solder a joint after applying any flux to the joint.

Can you Resolder a copper fitting?

Soldering vertical copper pipe shouldn’t be too different from working horizontally. If the joint and tip are hot enough, the solder should flow right in. Heat the middle of the fitting and apply the solder as soon as it starts to melt. Remove the heat once the solder starts moving.

What is the sponge for in soldering?

This wet sponge is used to clean the corrosion on the tip of the iron. A dry sponge does nothing but damage the tip. Every time you pull the iron from the stand, it’s a good idea to swipe the tip on the sponge just to clean it off and get a nice silver tip – it will allow you to solder much more quickly and cleanly.

Can you use lemon juice as flux?

Cut six lemons in half with a kitchen knife. Squeeze the juice from a lemon into the strainer. Stir the juice in the container for 10 seconds with the wooden spoon. The citric acid flux you have made can now be used to prepare metal for soldering.

How do you solder without soldering wire?

You can use anything that is able to heat a piece of metal up to the melting point of your solder (between 400°F / 200°C and 700°F / 370°C). Butane lighters work the best. But you can also use candles, oil lamps, alcohol burners, or even open camp fires.

Why is soldering so hard?

Soldering is a process somewhat like gluing, in that the solder has to form a tight bond between the parts. Just as clean parts glue better, they also solder better. Any mud, blood, beer, grease, oil, or especially oxidation will make the joint difficult or impossible to solder well.

Why does my solder stick to my tip?

Clean the iron using gypsum or wire wool (don’t file, especially with plated tips) and immediately apply solder to the tip. If you have done it properly, the solder will adhere to the tip. If you have done it incorrectly, the solder will melt in blobs and fall off.