how many amps for 1.5mm to 8mm butt weld

[paul r]

Hi,

How many amps should I be using to weld some 1.5mm exhaust pipe to a 8mm flange in mild steel?

I was told 35 amps.........but I reckon thats way too low? Tried it last night and I had to hold the torch for ages in the same place to get the weld pool going, by the time i had one, I'd blown a hole in the 1.5mm steel!!

I reckon more like 70 amps??

Thanks,

Paul.

 

[GrahamGKD]

Paul,
The table I use for TIG settings suggests it would be well over 100 (maybe even upwards of 200) for 8mm to 8mm TIG fillet welding, but I guess the flange is a relatively small piece of material and will heat up relatively quickly. Clearly you will need to focus most of the heat towards the thicker material. Start of with 80 or 90 and nudge it up if needs be? A foot pedal would help if you have one?
Graham.