Cutting And Grinding Discs: Matching The Abrasive To The Job
Matching duty cycle to actual workload, rather than just chasing the highest amperage figure, is the difference between a machine that keeps up with the job and one that keeps tripping out halfway through it, and it's a question worth raising with a supplier before you buy, such as Tec Products Ltd.
Space and power supply are the other two practical constraints worth checking early. Confirming that a chosen machine will run comfortably from the electrical supply actually available in the workshop, and that there's room to work safely around it with materials laid out, avoids the common mistake of buying a machine that then can't be used the way it was intended.
Abrasive discs look interchangeable on a shelf but perform very differently depending on what they're made from and what they're used on. Cutting discs are generally thin, designed to slice through material quickly with minimal heat build-up, while grinding discs are thicker and shaped to remove material from a surface or clean up a weld, rather than cut all the way through it.
MIG (metal inert gas) welding feeds a continuous wire electrode through a gun, shielded by a gas supply, which makes it fast and relatively forgiving for general fabrication, sheet steel and repair work. Jasic's MIG range is one of the more popular starting points here, covering entry-level compact units through to higher-output machines as work scales up. TIG (tungsten inert gas) uses a non-consumable tungsten electrode with a separate filler rod, giving a slower but tidier result that's favoured for thinner materials, aluminium and stainless steel where finish quality matters. MMA, or stick welding, strikes an arc from a flux-coated electrode and needs no shielding gas at all, which makes it the most portable option and a common choice for outdoor or on-site work on thicker steel.
The abrasive material itself matters as much as the shape. Discs formulated for steel typically contain aluminium oxide, while stainless steel usually calls for an inox-rated disc that's free from iron, sulphur and chlorine contaminants that could otherwise cause surface corrosion on the stainless. Aluminium and other soft, non-ferrous metals need their own dedicated abrasives too, since standard steel discs tend to clog quickly and produce a poor finish on softer materials.
Portability and power supply matter as much as the process itself. A stick welder will run from a generator or a domestic supply in places a gas bottle can't easily follow, while MIG and TIG set-ups need a gas cylinder and, for anything beyond light-gauge work, a heavier electrical supply. Workshop layout, the materials you weld most often, and how frequently the machine needs to travel are all worth weighing up before settling on one process.