Welding 1/4 aluminium advice

[yorkie_chris]

No all there is is current and wire speed unless it's hidden away

 

[Hood]

No all there is is current and wire speed unless it's hidden away

It is often in beside the wire feed.

 

[Hood]

Just looked at the manual and doesn't look like there is a burnback setting.

It is hard to tell from the pic and without actually seeing the weld in progress but you may have the voltage a bit too high.

 

[yorkie_chris]

Doesn't look like it and I can't see owt in the manual either

http://www.r-techwelding.co.uk/Downloads/ProMig250-1_Owners_Manual.pdf

 

[yorkie_chris]

Yes you will always get black smut, but around the weld there should be a cleaning zone. That is not present on the OP's welds.

I've never suffered excessively with the white/grey dust once dialed in.

I don't know what machine you've got but make sure your inductance is on 100%. Depending on shroud, if its an MB36 with a fairly large 15-20mm shroud get 18-21lpm of gas flowing through it. You want a 30+lpm flow meter on the regulator end and you want to check that at the torch with a Pea Shooter that goes up to 30LPM.

10-15mm of stickout and 5-10* degree push angle. Obviously push don't pull.

You want to get the wire into spray. For a 1.2mm wire around 23V and 11meters/minute of wire I guess.

My machine doesn't have any indication of voltage or wire speed, they just go from 0-10.
Cleaning zone on DC? I see that when I use TIG.
Machine is an R tech Promig 250

Cheers for the info on gas and angles

Inductance?

 

[Hood]

It is the DC that does the cleaning, with a standard Mig I never saw it all that much but with a pulse Mig is was very clear.
Don't think your welder has inductance setting.

 

[Hood]

Does inductance actually make a difference in spray? I was always under the impression it was more for dip.

 

[yorkie_chris]

It is hard to tell from the pic and without actually seeing the weld in progress but you may have the voltage a bit too high.

Not got many pics, will grab some more when I'm next playing.

Boat has to take a break this weekend as I need to stick new sills on my landrover.

 

[Hood]

Stickout probably too long. You only get cleaning action where there is ionization.

I should maybe qualify what I meant. With the standard spray it was there but not really obvious, with the pulse it is right in your face.

 

[Hood]

Not got many pics, will grab some more when I'm next playing.

Boat has to take a break this weekend as I need to stick new sills on my landrover.

Hard to tell from the pic as it is a bit fuzzy but they look ok from what I can see.

 

[Hood]

Just looked back at a pic of a weld I did with the R-Tech and I do see the cleaning action on it right enough, just not so obvious as it is with the pulse.

 

[yorkie_chris]

Will try a bit more gas and see if it gets a bit cleaner looking. I was probably using a bit too much torch angle as well

 

[Hood]

In your first pic, is that bubbles on the surface or contamination. If bubbles then I would say reduce the voltage a wee bit.

 

[yorkie_chris]

Will take a close look when I'm there, but I think they were just flecks of contamination not bubbles.

The bits were cleaned with a zip wheel on the grinder. Is that enough? Or should I be wiping them with thinners or something?

 

[Hood]

Unless they are corroded then really you shouldn't need to clean much at all with Mig, the bits in your pics look clean.