Most domestic UK properties are supplied with single-phase power, typically 230V, which is more than adequate for light-duty inverter welders used for hobby work, repairs and general fabrication. Three-phase supply, commonly 400V to 415V across three live conductors, is standard in industrial premises and delivers power more efficiently to heavier equipment, which is why higher-output welders and plasma cutters, including some Fronius and ESAB machines, are often offered in a three-phase version.
Flap discs sit between cutting and
http://warblog.hys.cz/user/LeomaNowak8223/ grinding in terms of use, combining overlapping abrasive flaps to blend welds, remove coatings and finish surfaces with more control than a solid grinding disc. Every disc also carries a maximum operating speed printed on it by the manufacturer, and checking this against your angle grinder's rated speed is a basic habit worth building into every new batch you open.
A gas lens sits in place of the standard collet body and uses a fine mesh to straighten the shielding gas flow into a smoother, more laminar stream around the arc. This generally allows a longer stick-out from the cup without turbulence pulling in surrounding air, which is particularly useful when working in tighter joints or awkward positions where the torch needs to sit further back from the work.
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.
Surface flatness and tolerance are the starting point, but fixturing is what turns a flat plate into a genuinely useful tool. Tables with a grid of holes or T-slots let you bolt down clamps, stops and jigs in repeatable positions, which speeds up repetitive fabrication and makes it far easier to hold parts square while tacking. A table without any fixturing options usually ends up needing extra clamps, magnets or improvised supports to achieve the same result.