Old Miller Big D2 worth fixing up?

[Isaac-1]

Let me start by saying I am not a welder, at least not a serious one. I may do little jobs when no one else is available, but tend to know too many people that do it for a living when it comes to working on anything serious. Anyway there is a skid mounted Miller Big D2 diesel powered welder sitting in the shed on the family farm, it has been sitting around being used very rarely for the last 20 year or so (I think it was built in the late 70's or early 80's). I can't find too much information on this model, Miller does offer downloadable PDF's of the operators manual, but there does not seem to be that much information included, key points 200 amps at 40V DC 100% duty cycle, current range 40-275 amps, one chart shows up to 300 amps at 40% duty cycle. The welder does run, at least it did the last time anyone used it that I know of about 2 years ago, but does have a number of issues, the battery charging alternator does not work, desperately needs new cables, course and fine adjustment scales faded to unreadable point, 2.5 kva 120V AC generator has no output at the plugs, muffler rusted, etc. So down to the question would it be better to invest in fixing up this unit or perhaps buy a (maybe used) more modern smaller lighter engine driven unit such as a Miller Wildcat / Bobcat for the occasional jobs that need to be done away from an electrical outlet or too big for the little wirefeed/MIG or old buzz box welders? I am a bit confused on available features of newer units, as well as the tendency of all the newer (at least lower end) units to be rated at 20% duty cycles, etc.

thanks Ike

[aametalmaster]

Maybe ask here, you may get some intrest...Bob

http://www.millerwelds.com/resources...isplay.php?f=3

[jht1057]

If it were me and this is the machine I have bought and paid for, runs and has been dependable when needed, along with the family history, I would spend the money to replace the small stuff and keep the machine.

A 100% duty cycle means you can light this welder up and run a single arc all day long with out the machine needing a cooling break.

[dkamp]

KEEP IT!

Issac- keep it- it's a gem. Put fuel in it, change the oil, and start and run it every so often. Put a shelter over it to protect it from the elements. IF it has auxiliary AC power output (probably does), you can use it as emergency power when the lines go down. As JT noted- it's a real workhorse- and substantially better than anything you'd get that's small-new-modern. If you're not an experienced welder, you'll actually be best-off learning on this one, because it will be strong and stable as a rock. Something small and light will sag and race under an unstable arc condition, this thing wouldn't vary output if the world stopped turning.

[Dempster]

I too say keep it and use it. If been sitting a while make sure it's clean inside no rats nests and such or you may burn something up later. Mice and rats get inside and hasn't been ran in a while no telling if all the insulation is good or something will fry next time you use it so clean it up good first. Many times one that has been sitting too long may need the brushes loosened up and clean the armature or new brushes but if all else is good that's not a big deal. New mufflers can be had reasonable or fit another new or used one on it. Advantage to the newer welders is many have 10 or 11KW AC generator output enough to run things at your house and a small well pump when power is out or lots of AC tools. If you wanted to do lots of welding all day long the one you have might be better or find someone that wants to work a trade with you on it.