Tin solder is generally used to join(or repair) zinc gutter elements or cold water pipes, to solder electronic components and to manufacture various objects, e.g. decorative objects. In this tutorial, we will see how to proceed to make a clean and quality tin weld.
The first rule for a weld is to take your time and to focus on the job. If you are welding along a wall or any other surface where the coating could be damaged by heat, use a flame arrestor without toxic fibers.
How to make a tin solder in a gutter
When welding two parts that are not horizontal, such as a gutter for example, if you want it to be permanent, it is strongly recommended to proceed in two steps. For a weld of this magnitude, you will use a tin rod sometimes called “targette” by roofing professionals.
Your work surface must be perfectly clean and dry. Brush the contact areas with a stripping fluid, such as acid. The trick is to first tin the joint between the two parts to be welded. Cover with tin, without overloading, while heating well, so the tin passes under the cover, behind the solder.
This first step ensures the solidity of your work, because the preliminary tinning allows the capillarity to take place between the two zinc parts.
It is now time to proceed with the second step to strengthen the weld. You can then load up, because the tin underlay holds the small heated tin balls much better. This is especially useful when welding sloping parts of your gutter. You don’t have to tin the horizontal bottom.
Draw tin lines, perpendicular to the border between the two parts to be soldered. Do not overheat, otherwise the tin will become too liquid and slip if your surface is not flat. You still have to spread the tin well, using your soldering iron tip.
How to make a tin solder between two copper tubes
To make a weld between two copper pipes, the two parts to be welded must be deoxidized with emery cloth. Don’t forget to pass the canvas through the inner part that provides the junction. The sanding is intended to create fine streaks for the tin to adhere strongly.
Then pass the specific paste with a brush to strip all the parts that will come into contact. Then assemble your tubes.
For fine pipes, you can sometimes use a tin wire coil instead of a rod.
Heat the joint between your two pipes with your soldering iron. Move the flame away and bring the tin wire close to the shoulder of the fitting.
Caution: the tin must be melted on contact with your sufficiently heated tubes, and not directly by the heat of the torch.
The tin melts and slides by capillary action. Continue until you cover the complete junction area. If necessary, bring the soldering lamp or torch closer to heat the tubes so that they are warm enough to melt the wire.
Beware of lead in the sanitary parts!
For all soldering that involves drinking water pipes, you must not use lead, which is a toxic product for our body.
At the end of your welding, wait a few minutes for the assembly to cool down, then wipe off any paint stripper residue with a cloth. If your solder is on a visible part, sand or file the joint to remove superfluous tin and to have an aesthetic finish.