spray transfer min. current - 1.0mm and 1.2mm steel wire

Hi there

Is the transition to spray transfer at a lower current with a smaller

1.0mm diameter (39thou) wire than with 1.2mm (47thou) wire?

With Ar-15%CO2 I reckon it's

1.2mm dia -> 240A 1.0mm dia -> 220A

What do you reckon?

Reason for asking is, at lower thicknesses, that might be enough difference to enable spray transfer to be retained, not some other mode. It seemed to make a useful difference for some box sections, for example.

I've never thought about it until recently because quite a lot of air-cooled torches can take 240A spray with 1.2mm dia wire, but overheat and ****-out with 1.0mm dia wire. Which can be understood

1/1.2 of contacting electricity pick up surface 1.2^2/1 = 1.44/1 wire feed speed increase

So in general you'd want 1.2mm dia wire when "spraying".

But with a water-cooled torch (gun) on an industrial machine - the torch can take spray with 1.0mm dia wire, and obtaining spray at a lower Amps might make that crucial difference enabling clean, smooth, efficient, fast spray transfer to be used on lower thicknesses.

Your experience says??