Welding ?

[rebocardo]

> my harvester and forwarder includes the following instructions

That is pretty much how I do it myself, I disconnect both battery cables too.

I have blown light bulbs with my MIG welder just because they were too near the work site, even though the piece I was working on had a good clamp and ground with the above precautions mentioned.

I do not know what killed them, except they all died in a week after the work. I think EMI might have been the cause.

[Slabs]

"IF" any electronic damage to anything is going to occur around it a welding operation it will be either from "arc transients" (high voltage impulses that occur when the arc is broken) or from misdirected high current flow due to  poor placement of the "ground" lead of the welder.  Leave the battery connected in all cases as it provedes a "buffer/supresser" medium for induced transients like it does for the alternator.  Disconnecting "electronic" circuits such as the pulse-width-modulator speed controls  ( as on the Misers)is a good idea but often not practical. On the tractors, put the ground clamp as close to the welding area as possible and weld away.

Good luck (though I don't think luck is an issue)

[SwampDonkey]

In most high schools around here up until a few years ago you could study welding in shop. I think they are bringing the trades back to the high schools now because they finally realized how stupid it was to drop it.  : That fool Premier Mckenna done that when he introduced call centres to NB. Dad had a number of books from school on welding and machining. He bought a couple of new potato harvesters since they first came out over the 40 + years he farmed here. He built both those all over and added automatic level, automatic height adjustment to the loading boom, speed belts instead of digger legs, shakers on the primary beds to clean dirt off the conveyor bed when the soil was quite firm after those dreary fall rains, teflon armoring to reduce wear of the steal along the sided of the conveyors, hydraulics to clean the air vac head, reinforced the frame. The way I see it, those things were only half built, dad finished them. :D