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top pic is 2mm plate with 10mm beside it. bottom pic is 2mm checker plate.
wyn
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In the left hand pic the weld on the left hand plate looks like it might have not been clean enough or become contaminated during welding.
I have had plenty of experience with that, being a bit too impatient
Make sure the join area is clean then clean it another couple of times. Maybe whatever you use to cut the sheet is leaving contamination on the cut edge.
I have had plenty of experience with that, being a bit too impatient
Make sure the join area is clean then clean it another couple of times. Maybe whatever you use to cut the sheet is leaving contamination on the cut edge.
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Even if its nice new sheet, the surface will be slightly dirty. I find a good wipe over with some scotchbrite is ideal for cleaning off just before welding comences. Just make sure you blow the fibres off after.
I think perhaps 2mm outside corner joints are not the ideal for learning on, have a go on some 3mm if you have any. its only 1mm difference, but a lot easier to weld.
The 2mm in the top pic, looks like you have tried to just fuse it together? Or was it too hot that you didnt have time to do the rod bit?
I think perhaps 2mm outside corner joints are not the ideal for learning on, have a go on some 3mm if you have any. its only 1mm difference, but a lot easier to weld.
The 2mm in the top pic, looks like you have tried to just fuse it together? Or was it too hot that you didnt have time to do the rod bit?
I did ad filler rod, but its a bit hit and miss with the amps i think. I keep the torch in one place until the molten pool appears, but sometimes by that time its melted. If i had an idea of what amps were needed depending on thickness of alloy it would help, but not sure if that varies from machine to machine.
Cut yourself some bigger coupons to practice on. Tiny coupons... there's nowhere for the heat to go which makes it a lot harder.
Machine, arc length, travel speed all make a difference as does the size (mass) of the weldment- small bits require large changes in amperage/travel speed as it gets heat soaked, much less effect with a larger fabrication. 2mm Al... i'm typically running around 90-95A but on proper fabrications rather than small coupons and usually with a pedal too. Without a pedal i'd use slope up to give a higher starting current (say, 120% of main current) if available or turn the amps down a tad after tacking up and increase travel speed to compensate for the part heating up. With tiny coupons amps may well need to be quite a bit lower, was welding tanks to a radiator core yesterday... 2mm sheet for the tanks, 1.6mm tube for the inlet/outlets etc yet was welding at over 100A (machine set at 120A) most of the time due to the heat radiating quality of the, err, radiator.
Have a read of this thread if you haven't already, best way to get to grips with it is to experiment methodically
Machine, arc length, travel speed all make a difference as does the size (mass) of the weldment- small bits require large changes in amperage/travel speed as it gets heat soaked, much less effect with a larger fabrication. 2mm Al... i'm typically running around 90-95A but on proper fabrications rather than small coupons and usually with a pedal too. Without a pedal i'd use slope up to give a higher starting current (say, 120% of main current) if available or turn the amps down a tad after tacking up and increase travel speed to compensate for the part heating up. With tiny coupons amps may well need to be quite a bit lower, was welding tanks to a radiator core yesterday... 2mm sheet for the tanks, 1.6mm tube for the inlet/outlets etc yet was welding at over 100A (machine set at 120A) most of the time due to the heat radiating quality of the, err, radiator.
Have a read of this thread if you haven't already, best way to get to grips with it is to experiment methodically
A stainless steel wire brush that only ever gets used for cleaning ally is a handy too.
