I posted this over on the Miller website, maybe someone here can help me?

www.millerwelds.com/education/projects/m...howthread.php?t=1126

"AJ." wrote:

Forget about 70 amp buzz boxes and hire yourself a 200-300 amp engine driven unit and get yourself some 7018 rods,4mm gauge, fold the stick so you can work on it,clean off the paint,put on the ground clamp near the job area,take the ground lead from the battery to protect the alternator,tack the four corners and the middle of the adaptor so it can't move and then weld it all round.
Good luck
AJ

That is an option, and may be one that I consider.

My welder can output 300 AC/200 DC amps: www.millerwelds.com/pdf/spec_sheets/AD8-0.pdf

Just don't have the generator to output 70A at 220V if I need it for this job...

If you use 1/8" 7018 at 120 amps or so, I would guess that 50 amps would run your welder. 1/8" rod is easier to run out of position than bigger rod, especially if you haven't had that much practice welding. You will have to just make more passes than with bigger rod. Preping the steel before you weld affects the quality as much or more than your expertise with a welder. Make sure there's no paint, grease or dirt where you're going to weld. Make sure all the slag is ground off where the welds were cut off the mounting plate. If you have to make a vertical weld, weld uphill, not downhill. Its too easy to get slag in the weld when you weld downhand. I wouldn't say that I'm a welding expert, but I weld just about every day.

Well, I'm going to give my welder & generator a shot...

If I'm not satsified with the weld I either rent a welder or hire someone to come out and weld her up...

I gotta get this thumb action going, have many stumps & logs to deal with...

Just a suggestion, when you prep the stick and the mounting plate before welding, grind off all the paint on both, not just around the edges where you are going to be welding. It might sound like overkill, but trust me, it isn't.
I was at the local Cat dealer a few years back, and they had a 350 excavator pulled up be the rear door, there was a local welding contractor's truck pulled up beside it, and a hydraulic thumb sitting on the ground next to the stick. I saw where he had ground all the paint off the stick full width, and about a 3 foot long section. I thought "gee, this guy must be getting paid by the hour to mount that attachment" I figured I would have just ground clean around the outer edge, then welded away. Then a couple of years ago, I wanted to stiffen up a bucket on my farm tractor by welding on a piece of flat plate about 8 X 10 inches before mounting a lifting hook, preceded to just grind around the outer edges and weld away. After tacking it on at the four corners, I proceeded to weld around the perrimiter, but half way around, the expanding gas from the paint burning underneath kept blowing my welding bead away. I learned my lesson the hard way, when you see the experts doing something, it is for a reason.
By the way, how has the machine been running? I know when you bought it you were a little concerned with overheating?

George

Well, I didn't think I'd ever see this again. A friend of mine ran dozers for years and did his own welding.......with a home generator and a little 220V AC Lincoln cracker box welder. It seemed to work just fine for 1/8" rods down in the 120 to 150 amp range. The dang thangs would even burn LH 70-18 welding rods, only AC machines I ever saw that would burn LH 70-18's. Just needed to stick the rod to the metal a few seconds to warm them up or put them in a hot box before welding. Once you got them warm enough to stike a consistant arc, they welded as well as a DC machine.

I'd say it's worth at least a try.

Trucker, yep, I always grind to bare metal on all surfaces...

I don't know about the overheating part. Turns out the engine is only a couple years old, it's a reman.

Both the Rad and HYD cooler are somewhat new too, with no debris in them...

I have not run it in hot weather yet, so don't know for sure, so far it runs great...

Started all winter long no problem...

I did have a pump pressure line blow (somone made their own hose instead of buying a CAT hose, had screw on type fittingsm blew the fitting off, lost 65 gallons of oil), cost me quite a bit to replace that hose and the lost oil... So far that has been the only problem, but I'd only used the machine maybe 10 hours...

Yeah, 7018 LH DC rod can be welded with an AC Lincoln cracker box....and a few other brands of AC welders. It's hard, very hard to do....at least for me, but I learned how to several years ago. Actually, I finally kinda learned how before I found out they were primarily DC rod.
An 'ol pipeline welder cued me in, as well as showed me a few tricks too.
I've welded lots of big thick stuff with 7018 & 8018 on that AC Lincoln before I ever got my DC welder.....finally got fairly decent too. If I didn't like the looks of my welds, I just never fessed up to being the welder.....

I always had to run 7018 a few amps hotter than with DC welder....& it's harder to to keep 'em from sticking using an AC welder.
And it do help to preheat the rods.

A few year ago I finally ran up on some AC7018 rod & bought some to try on my AC welder.....but I never liked them. Worked OK for me flat, but no other position.....I can do better with DC 7018 on the AC welder or the DC welder.

But this is just me!!! When I think I'm welding really good, I just go down the street & watch the pros weld good, pretty, & Right!!!

sigh...oh well, in my next life I'm gonna be a rocket scientist....rich banker, or something easy........

Hey ttman4....if you make it to that "easy" life, .....will you adopt me?.....I could use an easy ride for a while myself too......LOL

The best welding process, you should need are Basic coated electrodes, and a D.C. welder with variable voltage and amperage controls, I have a Lincoln Arcmaker S.A.E. 300 (pipeline welder) these are as good as it gets for stick welding , it is important to follow the instructions on the w/rod box as to the pre-drying of the rods, this is important to limit the Hydrogen parts per/mill in the weld, I always remove thick paint from the weld area, if it is to fit an attachment, it is best to only tack in place then check it is in the right location by testing it trough its cycle, for the best results it would pay to use 3.2mm rods 450mm long, as these would give the most control over heat and skill, vertical welds start at the bottom going up , dont try any crap starting at the top down , if you read the box it will state the min voltage for the rods, this is also dependent of the atmospheric conditions, I could go in to this subject in great depth, as I have done loads of pressure welding,(Pipeline) now I am only interested in perm/ welding Bridges/Piledriving, basic coated (Sand) rods leave a slag that looks like glass, this is what glass is Sand,
tctractors