If you follow the best design, then joining of the thick parts to the thin ones should be as less as possible. In situations where we have no option but to attach the thick to the thin, there are certain basic rules that have to be kept in mind for it to be a success. The part that is thicker will always be capable of absorbing more of the heat than the part that is thinner.

The thermal conductivity of the metal and their after effects on the process of welding should also be taken into account. A metal like Aluminum is capable of absorbing a lot more heat than metals like stainless steel or steel. In the process of welding a thick metal to a thin one, we have to pay attention to the correct setting of the amperage lest we burn the thinner metal in the welding process – if the level of amperage setting is adjusted to low so that we can avoid excess melting, the heat may not be sufficient to melt the thicker part and similarly,

if the level of amperage setting is adjusted to high so as to get the thicker part more heated up, there is the risk of melting or burning away the thinner part. The ideal approach will be to apply the right amperage on the thinner metal. Making use of a torch or such heating tools, we should warm up the thick part to such a level that it welds to the thin part without any issues. Following this method will also help to improve the effective heat that we are able to produce with other smaller welding machines also. If the base material is preheated, it will make the welding of the two parts –the thinner and the thicker – easier than it is usually.

Another approach would be to adjust the amperage in such a way to weld the part that is thicker first. In the process of welding, we have to just slightly kiss the rim of the thinner metal and concentrate on focusing the major part of the heat to the part that is thicker. When using this technique, the angle of the electrode and the torch play a major role. Having sufficient filler metal on the joint will help to act as a fire extinguisher of the part that is thin.

There is still another option that we can make use of, if there is a welding issue with the thick and thin metals. We have to keep a heat sink behind the thinner part. Any premature melting of the thinner part can be avoided by placing a piece of brass, copper or aluminum behind the thinner part in case there is any delay for the thicker part to melt. The trick is to clamp a block to the back of the sheet plate.

We can also insert a solid bar or rod into a pipe or tube which also just as effectively. Being able to machine a portion that fits is sometimes the ideal way to create the necessary tooling or heat sink. Having a few bits of copper or aluminum will come in really useful while carrying out these procedures. Be imaginative in your application and use since there are many “right” ways by which a welding issue can be tackled. When the parts are of nickel alloys, titanium or stainless steel,

we will have to use a purge of inert gas behind the thinner material so as to ward off contamination, formation of excessive carbide or sugaring. In case the thinner metal is burnt through and we haven’t made arrangements for an inert purge, then there is the risk of damaging the metal beyond any repair. We must be extra cautious and make sure that the amperage settings are in accordance with the specifications of the welding procedure and not to overheat these metals.

Refer the Longevity website (www. Longevity.inc.com) or check out YouTube Channel (https://www.youtube.com/user/longevitywelding) for more information and details about the different equipments used for the many welding and cutting procedures. Longevity has all the right machines for your exact application, so do check out and choose what best fits for your product, materials, and requirements.