Opinions please....

[Wanderingmiles]

Hi All,

With more knowledge here than you can shake a stinky stick at could I have some opinions on my practice pieces please.....

I think they look ok, but worried that there was too much heat or not enough penetration. Lower weld (left) is a lap weld and the other a 90.

2.5mm steel using 2.4 Lanthanated (not that well pointed though, until the diamond wheel comes) and 1.6 filler (don't have 2.4mm) on the 90, no filler on the lap weld. Using pure argon at about 8lpm

Seemed to take about 65 amp which seems higher than the Ceriated or the 1.6mm.

Cheers all

 

[craigthewelder]

The lap joint doesn't look to bad, the fillet looks way to hot.Did you weld that after the lap joint??

 

[Wanderingmiles]

Thanks Craig,

I did weld the fillet after the lap, so it was warm i guess!

What I dont understand is this too hot bit, do I go cooler by reducing the amps?

Cheers

 

[Bsmith]

2.5mm steel using 2.4 Lanthanated (not that well pointed though, until the diamond wheel comes) and 1.6 filler (don't have 2.4mm) on the 90, no filler on the lap weld. Using pure argon at about 8lpm

Is lanthanated better tungsten than thoriated plz? Thanks, Brian (",).

 

[Wanderingmiles]

First time i've used Lanthanated but they are good for DC and AC and I'm a tight sod! They seem to need a higher amperage though! Also not radioactive!!

 

[Wozzaaah]

Thanks Craig,

I did weld the fillet after the lap, so it was warm i guess!

What I dont understand is this too hot bit, do I go cooler by reducing the amps?

Cheers

When someone says you're running too hot they mean just as you say, the current is too high for the material or technique.
Your fillet shows 'undercut' in places. There is basically a 'channel' melted between the edge of the weld and the parent metal and is often caused by having the current too high.

 

[hotrodder]

There's loads of variables that alter amperage requirements but 65A is rarely going to be too hot for a fillet weld on 2.5mm steel. Losing the millscale will make your life easier, it also helps with undercutting but the millscale isn't the cause here. Larger coupons will help a lot too- with tiny offcuts there's nowhere for the heat to go.

From the pic i reckon excessive arc length could be one of the biggest problems- at the left of the pic you posted... looks to be a void at the root of the joint where you ended the weld. You could break the weld open but one of the best ways to check fusion/penetration of a fillet and lap weld is to section and etch it

 

[Wanderingmiles]

Thanks Hotrodder, I recon you're spot on. The back of my welds look burnt as per your pic and the same with the void at the end of the weld - something I suffer with most welds!

I'll have a prectice this weekend and post further pics.

Cheers