multi pass tig

[brendan h]

in a bid to get as much info as i can and practis it. i am stuck. what would a tig welder do if he needs to weld some 4.2mm walled pipe with a 32NB (about 42mm OD)
now all i have is 2.4mm wire and keep getting undercut. gap of about 1.6mm and a root face of about 3mm. its probaby wrong but thats what i am asking. what would be the correct way?

 

[Drains]

Undercut means too high amps. So tell us Brendan, what amps you on?

 

[snowcat]

whats with the multipass, avarage pipe job is open TIG root, followed by MMA work, Hotpass, Cap.......what position????

 

[brendan h]

amps where at about 100. this is just me practasing welding and i have some scrap pipe to weld.