I'm attempting to weld some 50mm body washers to the bottom of the 30mm tube feet
(Wrote this yesterday but didn't send)
By the way, they aren't the dimensions that matter.. What matters is the
thickness of the steel and how clean it is/whether it's coated in anything (ie galvanised).
I've a similar welder and I use this table to give myself an idea:
.. though on mine the wire feed speed is generally a whole number less than the table. Make sure your tip and drive roller are right for the wire diameter and use lower powers when using flux cored gasless wire
Start on a piece of test metal of the same thickness first, that you can see both sides of. Looking at the flip side gives you an idea of how well the heat penetrated.
Grind an area smooth on the workpiece to get a good earth connection (the earth clamps on cheap welders are typically carp btw), set the piece up so your torch is angled downwards and imagine the metal weld pool is water; will it run away anywhere? (welding vertically is tricky for beginners, weld on the flat instead)
Gas on, settings set, hold the torch so the collar end does not touch the work, but there's about 5 - 10 mm of wire sticking out of the torch, and ensure the collar is clean inside, no blobs of weld stuck to it. Autodimming mask and bright head torch work well
Strike the weld and weld a line by moving the torch tip in very small circles while you proceed smoothly along (and probably faster than you'd think), listening as you go. If the sound is pronounced and distinct "pap pap pap pap" your feed speed is probably too low. If the torch bounces in your hand as the wire stabs the work the feed speed is too high. If the sound is like a constant hiss, without any sharp crackle/pap sounds again it may be too low, especially if the arc crawls up the wire and welds the wire to the tip.
Then stop and look at the weld you've done; here's the difference between a good and a bad weld, in terms of fusion between the weld bead and the substrate:
I mean, no critical parts to your job so if it's a bit "perched on top" it's not a train smash .. but if you're finding it looking more like the one on the right, you may need to up your 12minmax settings so you're running hotter - this is where the thickness comes in, as thicker metal sinks more heat. If you go too high you'll probably burn a hole in the metal substrate if it's thin. Easiest way to fill it in is to spot on and off to give the metal time to cool otherwise the weld pool will just flow away from you
