Joint Repairs

Aluminum joints made with fluxless Alumite™ solder have been evaluated by Bell Laboratories and found to be permanent, corrosion resistant, and stronger than joints made with other solders. To solder Aluminum, the invisible oxide film must be penetrated by the solder to obtain metal to metal bonding. This can be done simply and effectively without chemical flux by using Alumite™. It is only necessary to heat the area to be soldered to a temperature that will melt the end of the solder stick as it is drawn across the heated Aluminum surface. The solid end of the solder stick first punctures and loosens the oxide layer and allows the solder to flow underneath. This is known as “tinning the surface.”

Many types of repair and construction are possible using this fluxless technique. However, the Aluminum surface must be accessible to stroking by the Alumite™ solder rod. The rod will not flow by itself into the capillary joint. To promote capillary action, companion Kapp Lunar Flux is required.

Butt Joint

Ends are always beveled and brought together. Follow the tinning procedure outlined above, stroking both beveled surfaces of the joint with Alumite™.

ALWAYS USE A NEUTRAL FLAME!
ALWAYS KEEP THE FLAME IN MOTION!
ALWAYS COOL SLOWLY!
NEVER PLUNGE THE HEATED PARTS INTO WATER!

T-Joints

For maximum strength, tin both members as described above and bring together. Heat the parts and flow a fillet of solder into the intersection. Fillets are made by running the solder stick along set-up members where contact is desired. Let the heat from the members, NOT FROM THE FLAME, melt the solder. Run the solid end of the solder stick through the molten fillet to remove any trapped oxide.

In many cases, adequate strength can be obtained without pre-tinning. However, when the members are not pre-tinned, the fillets alone support the joint load, as the members are not joined to each other but only the fillets.

ALWAYS USE A NEUTRAL FLAME!
ALWAYS KEEP THE FLAME IN MOTION!
ALWAYS COOL SLOWLY!
NEVER PLUNGE THE HEATED PARTS INTO WATER!

Lap Joints

Parts can be tinned and slid together while the solder is still molten. Alternatively, a generous fillet of solder can be applied to the edges of the lap joint, making sure of tinning by running the stick through the molten solder.

ALWAYS USE A NEUTRAL FLAME!
ALWAYS KEEP THE FLAME IN MOTION!
ALWAYS COOL SLOWLY!
NEVER PLUNGE THE HEATED PARTS INTO WATER!

Mitered Joints

Mitered joints can be found in windows, doors, screens, frames, etc. Members should be solidly jigged. A neutral flame is played over the joint area until the Alumite™ will melt when drawn across the joint. Make sure of tinning action by drawing the solid end of the solder stick through the molten solder deposit. After tinning, the joint may be built up and finished as desired. These joints are stable in high humidity and have remained in perfect condition after many years of exposure.

ALWAYS USE A NEUTRAL FLAME!
ALWAYS KEEP THE FLAME IN MOTION!
ALWAYS COOL SLOWLY!
NEVER PLUNGE THE HEATED PARTS INTO WATER!