Newbie Rod\Amps

[dragonfly]

Hi, I've been hanging around reading threads and tutorials for quite some time. I have had my Dads old BOC Transarc on long term loan for quite some time, and been playing with welds gradually improving, reading abit more, trying again etc. However yesterday it finally gave up the ghost, (well started get temperamental, I think the switch is on the way out) and because I was mid project, have no patience, and felt I had graduated from pigeon poo welding to been able to do a half decent weld, I splashed out and went halves with Dad on a Clarke AT131.

I haven't even powered it up yet, but on the BOC there is a slider that links amps to rod size. I always dialed it to my chosen rod, then tweaked it up or down depending on the planned weld\feel etc. i.e. tweaked it down abit for welding upwards etc.

However the clarke only has an Amps dial, which is fine, but I'm mising that initial starting point. Is there anywhere I can find a table of approx amps to rod thickness, just to give me a rough starting point. ( have looked on-line but I must be searching the wrong thing)

 

[rtbcomp]

Welcome to the forum.

There's usually one on the box the electrodes come in.

 

[spaf4]

Simple really. When you find yourself happy with the welds you're putting down, then you have found the amperage that suits you. Amperage isn't set in stone and each welder will have their favoured settings. Some prefer a higher or lower setting to others. However, as a guide. When I used AC current, amperage for different sized rods would be around ...2.5mm 80-90 amps, 3.25mm 120- 125, 4mm 150- 160, 5mm 212- 215, 6mm 250-260. Now, since just having started using DC current I've found that I've had to reduce my settings to...2.5mm 60-70 amps, 3.25mm 80-90. I haven't yet tried a 4mm rod but I expect 115- 125 would be enough.

Furthermore, different rods run better on different settings and you'll also find yourself altering your setting when you move onto positional work. It can sound like a minefield at first, but once you gain experience and confidence things will fall into place. For now just keep on practising on simple butt joints and fillet welds until your happy with what you're putting down, then you can move on to the challenges that come with learning positional work. Just have fun and keep up with the practise and you'll get there.

 

[TechnicAl]

40 amps per mm
2.5mm = 100 amps......and then tweak

 

[gordon stephenson]

You know TechnicAl is the man!! also equates to 1amp per 0.001" (thou) or there abouts.

 

[TechnicAl]

You know TechnicAl is the man!! also equates to 1amp per 0.001" (thou) or there abouts.

is that right

how many thous in a mm?

40?

 

[hotrodder]

Near as damn it, 1/25.4 = 0.03937...

 

[dragonfly]

40 amps per mm
2.5mm = 100 amps......and then tweak

That I like, easy to remember, and gives me the starting point to tweak from.

Thanks

 

[Jester]

Yes, easy to remember. Wish I'd heard it before

 

[PTvor]

Or express the rod diameter in thousands of an inch (3.2mm = 1/8th inch = 0.125 inch = 125 thousandths) then set the current to the number of thousandths - 125A for a 1/8th inch (3.2mm) rod.

But, it's only a starting point and you have to see how the rod runs, and they all have different ranges written on the packet, and burn differently, and seem to need less amps on DC than AC, and the dials on welders aren't necessarily very accurate.

On my inverter, 2.5mm 6013s run hottish at 80A, I use 75A, and 3.2mms at 125A are impossibly hot, 105 to 110A is better.

You just have to see how the particular brand of rod runs and adjust the current. You will probably have to tweak for position as well.

 

[dragonfly]

First impressions on the Clarke Inverter (From a newbie) -

The leads are a touch too short for my liking, mainly because I'm used to working with the longer leads on the heavier BOC, only a minor gripe really, because it's that light I can move it all the time to wear I'm working, I'm just used to having the heavy BOC out of harms way (grinders etc.) and having a longer reach. More of a case I need to change my habits, rather than a problem.

Slightly more is the current knob is way too easy to turn. A couple of times I've gone to tweak it up or down, and because I've got gloves on, I've knocked it wildly in one direction. Again I'm used to a thumping great mechanical turn level thing on the BOC, again I'm sure I'll get used to it.

On the plus side, my welds are definitely better, and the slag, comes of so much easier, with the same Toolpak rods, (I must get a pack of Murex or similiar to try), I've been using 2.0mm rods for my current project, and working between 60-80 amps, depending on position etc. And I can't get over how quiet it is, and the case doesn't rattle and vibrate itself apart

 

[wheresmejumper]

Slightly more is the current knob is way too easy to turn. A couple of times I've gone to tweak it up or down, and because I've got gloves on, I've knocked it wildly in one direction. Again I'm used to a thumping great mechanical turn level thing on the BOC, again I'm sure I'll get used to it.

you need the steady hands of a surgeon to turn the dial on my inverter

id be lost without the digital display