help with hobart tigwave 250 ac/dc setings

donald · Tue Jun 17, 2014 1:24 pm

Tried my first tig weld, didnt work. using an older hobart tigwave 250 ac/dc, welding steel 1/8, amps about 75, foot control. i get a good arc but only the tugston tip get hot then melts into a blob. the hobart has many control options so im sure ive set something wrong. any ez answers? thanks, don

AFSATCOM · Tue Jun 17, 2014 1:30 pm

What polarity are you running. If you run DCEP it will melt the tungsten real quick.

donald · Tue Jun 17, 2014 1:49 pm

electrode is neg DC, high freq - continous, arc force -7, pre flow -.3, crater fill - 6. I know the DC part but dont know the EP vis EN or how to change it. OOO i think i get it . . . is EP electrode positive and EN electrode neg?

AFSATCOM · Tue Jun 17, 2014 2:03 pm

Switch to electrode positive andnfire it up again. If it works right then your leads are installed backwards.

AFSATCOM · Tue Jun 17, 2014 2:13 pm

DCEP = dircet current electrode positive also called reverse polarity or DCRP
DCEN = direct current electrode negative also called straight polarity or DCSP

Tue Jun 17, 2014 6:23 pm

donald wrote:electrode is neg DC, high freq - continous, arc force -7, pre flow -.3, crater fill - 6. I know the DC part but dont know the EP vis EN or how to change it. OOO i think i get it . . . is EP electrode positive and EN electrode neg?

High freq should be set to "start", not continuous, as well (for steels). The "continuous" is for HFAC welding on aluminum and some other non-steel alloys. By the way, the "arc-force" has no function in DC Tig welding. Arc-force is a stick welding setting, and the control may double as "arc balance", which only functions in HFAC welding. I'll hunt up an image of the machine, and see what else I maybe able to share.

Steve S

Tue Jun 17, 2014 7:04 pm

Here's the manual for that machine (or an identical model, under the ThermalArc label). It was a real bear to find!

http://www.thermadyne.com/IM_Uploads/Do ... 29-127.pdf

As for the comment about having the torch/ground hooked backward, each image I viewed while searching this contradicted the last one...

The manual says the bottom left terminal should have your ground clamp attached, and your torch should be on the bottom right terminal, for the main switch (EN/AC/EP) to function as marked.

Hope this helps!

Steve S

donald · Wed Jun 18, 2014 4:16 pm

got it working . . . just ok, i need to learn how to weld with tig now thanks.

Wed Jun 18, 2014 6:29 pm

donald wrote:got it working . . . just ok, i need to learn how to weld with tig now thanks.

Getting the machine to do what it says it's doing is half the battle, especially when you're new to it, and can't gauge what's wrong.

If you're a patient man, it actually gets easier from here!

Steve S

AKweldshop · Wed Jun 18, 2014 7:42 pm

donald wrote:got it working . . . just ok, i need to learn how to weld with tig now thanks.

Hey,
Get us some pics of your welds.
We can give you some good tips and pointers.

John