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Welding progress - improving, but may need to reweld the first joints
nick205 - 18/6/13 at 10:34 AM

OK - I'm getting the hang of it a bit better, but grinding down some of my first welds has revealed the need to reweld.

First pic is one of my latest attempts; V ground edges, slight gap and blow torch pre-heat on the thicker part.



second pick is one of my first welds, ground back to check it. Looks to me like it needs re-welding or it will crack?

Daddylonglegs - 18/6/13 at 10:49 AM

I'm no welding expert by any means, but I think I would re-do the lower one personally

Just my humble opinion

Slimy38 - 18/6/13 at 11:11 AM

I wouldn't have expected to still be able to identify the edge of the metal once it had been welded, so more like the first one.

deezee - 18/6/13 at 11:31 AM

The 2nd photo shows a complete lack of weld penetration. Not enough amps or too quick. Either way you could probably snap that over your knee!

Mr Whippy - 18/6/13 at 12:26 PM

quote:
Originally posted by deezee
The 2nd photo shows a complete lack of weld penetration. Not enough amps or too quick. Either way you could probably snap that over your knee!


Yeah not even close to enough power, I'm amazed you haven't melted the edge even a little. Turn the wire speed done and the amps up a setting.

Get some off cuts and practice on them, weld only one side and then rip the weld apart with a bar to see how far it has melted through, which should be the full thickness.

[Edited on 18/6/13 by Mr Whippy]

nick205 - 18/6/13 at 12:51 PM

Amps on full already!

What I thought was a 120A machine, tops out at 110A as well.

Have the wire speed down as far as I can without stuttering.

On that first weld, I don't think I was zig zagging enough over the edge to get the heat into it.

Still practicing!

hughpinder - 18/6/13 at 01:09 PM

I would think 110 amps was plenty - check your earth is secure and the metal clean. Over the years I've replaced the earth leads on a couple of cheap welders, for a decent clamp and heavier earth cable, and its has made quite a difference to the weld quality (clamps are about £2 from a decent welding supplier and the cables a couple of quid a meter.)
Regards
Hugh

Slimy38 - 18/6/13 at 01:17 PM

quote:
Originally posted by nick205
Amps on full already!

What I thought was a 120A machine, tops out at 110A as well.

Have the wire speed down as far as I can without stuttering.

On that first weld, I don't think I was zig zagging enough over the edge to get the heat into it.

Still practicing!


Check the other end then, the grounding clamp. I messed up a whole batch of welds before I realised my clamp was only resting on the metal rather than properly attached. A bad clamp gives the impression of poor power.

My welder is a 150A, but I've got it on setting 3 and it works perfectly on the 16 gauge chassis metal I'm using (even blows through if I'm not careful). Unless you're using much thicker metal I'd expect it to not need max amps.

Edit: Just rereading your post, you're having to use a v groove and preheat? I think there's something wrong with your welder, or you're doing 6mm plates!

[Edited on 18/6/13 by Slimy38]

nick205 - 18/6/13 at 02:17 PM

Thanks gents.

Checked earth clamp and all OK, but spending much more time prepping the steel before welding makes a big difference. Done a few more test pieces with close to full penetration and a much smoother finish too.

More pics later.

encyd - 21/6/13 at 10:06 AM

What gas are you using? I found my joints improved immensely when I moved to CO2/Argon mix instead of just CO2. I'm no expert by far but it helped me!

40inches - 21/6/13 at 10:38 AM

I have always preferred .6 wire, you can turn the wire speed up, have used .8 but just prefer .6

nick205 - 21/6/13 at 11:07 AM

quote:
Originally posted by encyd
What gas are you using? I found my joints improved immensely when I moved to CO2/Argon mix instead of just CO2. I'm no expert by far but it helped me!



Argoshield gas.

nick205 - 21/6/13 at 11:08 AM

quote:
Originally posted by 40inches
I have always preferred .6 wire, you can turn the wire speed up, have used .8 but just prefer .6


tried both, but can't seem to get 0.6 to work as well - maybe not high enough wire speed.