Need some welding advice

[FORDification]

OK, this post might be kinda long, but I just wanted to be as thorough as possible.

I'm using a new MIG welder to weld in patch panels and for general rust repair on the cab of my truck...but I'm having some major problems. Here are the specs and materials I'm trying to weld with:

- Hobart Handler 175 (set Electrode Positive for solid wire)
- ER70S-6 (.024) wire
- shielding gas (75% Argon, 25% CO2), set at about 30# pressure
- Voltage setting 1 (as low it will go)
- Wire speed - about 45
- app. 1/4" stick-out

I tried welding up the gas tank filler hole in my cab last weekend as practice for getting started on all the rust repair, but I was completely embarrassed about how it turned out. In fact, I wasn't even going to post these pictures, but decided to bite the bullet and do it anyway...I mean, I want to do this right, and while I might cause a few of you out there to chuckle at this butcher job, if you can give me some tips and pointers about how I can do things differently, I can handle it.

The problem is that I can't seem to NOT burn through the metal. Almost immediately upon touching the metal, it burns through. It's like the voltage is just set too high...but I've got it turned down as far as it will go! I know that you have to hit a balance between voltage and travel speed, but I'm not even getting a chance to start moving before it burns through.

When I started burning holes, I then tried to just hit and miss very quickly to basically fill the hole. I figured I could grind it down later to be invisible. I didn't take any pictures BEFORE grinding it down (it was too gruesome to look at), here's a shot taken after grinding it down:



It doesn't look TOO bad in this shot, but you can see that it ain't pretty. However....here's a view of the backside:



OUCH! As you can see, I'm getting virtually NO penetration. In the second picture at about the 5 o'clock position there's actually a hole burned through, with a very thin filler weld on the front side to cover it up. It almost looks like I could give a good whack on the backside of this and knock the plug right out...which is actually what I intend to do, so I can re-do it.

Before I do any more welding on the cab itself, I'm going to be cutting up an old door skin to practice more butt welds on. But I was hoping someone could give me an idea or two about what I'm doing wrong and how to improve it. I'm not after a pretty weld, since it'll be ground down smooth anyway....but I DO want good even penetration.

I bought this welder a couple years ago when I was working on a Studebaker truck project, because I needed something capable of welding thicker metal, since I was going to have to shorten the frame. However, the Stude project got sold when I decided to do this Ford instead, before I even got a chance to fire the welder up, and so this is what I have to use. So did I just buy TOO MUCH welder??

Any thoughts or suggestions would be appreciated. I'm also going to be posting this message and pics to the Hobart Welding Talk messageboard in the hopes that some of the experts there can help me out.

[Ford390pwr]

Hey Keith, I just checked your post oevr at the Hobart site and I am learning a lot! Of course, I have never touched any welding equipment, so I am sure I could learn a lot!

Anyways, it looks like they might get you the help that you need to sharpen your skills! I will be watching the progress of this one.

[Randle]

Keith

Your Hobart welder is a tapped machine, the wire speed knob also controls the amps. On my HH 135 Hobart the chart in the door says to set it on 1/45 but I have found that on 20 & 22 gauge metal to cut your wire speed back to 20 or 25 and it does much better. Hope this helps.

Randle

[FORDification]

Thanks for the tip, Randle. That's what I'm hearing on the Hobart messageboard too. I didn't realize the speed dial also controlled the amps, so when I was burning the wire up too quickly, I thought I was feeding it too slowly, so I kept bumping the speed up and trying it. Knowing how the amps are controlled now should make this go a lot easier. I'm looking forward to getting back into the shop to start doing some practice welding.

[morganater]

Hey Keith, I have the same exact welder you have, if not maybe just a little different model. I was having the same exact problem When i was welding in some metal for the floorpan on my 68. I eventually got it done, but had very similar symptoms to you. Tell me what you find out. I actually haven't done any welding since then.

[Randle]

Another thing I just noticed, in a shop where not a lot of air is moving you can turn your gas back to about 15. Outside or if more air is moving you will need to turn it back up, you need just enough to shield the air off the weld. This won't make the weld any different, but it will save a lot on gas.

[willowbilly3]

That's right, and I've found they won't weld at all if there is a slight breeze.

[FORDification]

Hey Keith, I have the same exact welder you have, if not maybe just a little different model. I was having the same exact problem When i was welding in some metal for the floorpan on my 68. I eventually got it done, but had very similar symptoms to you. Tell me what you find out. I actually haven't done any welding since then.

Read THIS THREAD at the Hobard Welding Talk messageboard. Someone there also mentioned something about my having the gas turned up a bit too much. I hope that by following some of these suggestions I'll have better luck.