welding grounding

Jeff7131

I need to weld a small crack on the inside of a wood stove. I have access thru the firebox door but I am unsure on grounding for proper safety. I will be using a stand alone generator with plug in welding machine at 120 volt.

I know I need to gound the workpiece(woodstove ) to the welding machine. Do I need to have a separate ground from woodstove to building. I will probably come in contact with woodstove during welding due to limited workspace. If woodstove is grounded do I need to provide insulation between myself and and woodstove

Speedy Petey

No, just the ground from the stove to the welder is fine.

I would also post this to a welding forum. Wood stoves are typically cast iron. Welding cast iron is extremely difficult. You may want to consider brazing it if that would work for you.

__________________
Sometimes I feel like if I answer any more questions it is like someone trying to climb over a fence to jump off a bridge and me giving them a boost.

Jeff7131

Thanks for the comment. I have already checked the material and it is steel not cast iron.

Everthing I read indicates to not come in contact with workpiece to avoid shock. Will the ground to the portable welding machine be sufficient if the welding machine is not grounded separately ???

Billy_Bob

It sounds like you have read the instruction manual which came with the welder. Best source of information if you have not.

Other than that, I would suggest calling the manufacturer of the welder. And sometimes manufacturers have additional information on their web sites along with regular instruction manuals. Might want to search google.com for the manufacturer's web site.

Stubbie

In arc welding the work piece is a part of the electrical circuit. Your ground connection completes that circuit with the welding machine. Whenever you are forced to be in contact with the material your welding you should wear the protective clothing and gloves necessary and insulate yourself from the work piece. Lay on an insulating matt of some kind. Now having said that you will see many people welding that don't bother insulating themselves from the work piece. In most cases as long as the "better completed circuit path" exists through the electrode and ground connection with the machine you would not likely take an electrical shock. But common sense tells you that being in contact with the electrical circuit while it is live is not a good idea. If your ground connection should jump off the work piece and you somehow get in series with it (cramped space) and the work piece you might get nailed. So just make sure that you are insulated from the work and the electrical circuit and you will do just fine.
No extra ground needs to be run to another grounding source. But if it existed that would seem to me to be rather dangerous to have another path that might complete the welding circuit.

__________________
" One nice thing about the NEC articles ... you have lots of choices"

Stubbie

Salem747

The good thing about a welder, as long as you have the plug wired properly, is that unless you have a good ground, nothing will happen. Wiring a 220V welder is funny too because what you have in the plug are the 2 hots and the ground! No neutral!

Yoyizit

From the welder schematic in front of me, the voltage at either welder terminal is undefined with respect to power line ground, so insulate yourself from anything grounded, like water pipes, house ground wires, etc..

If you are ungrounded and touch one welder terminal you won't be shocked because there will be no current flow through your body.

You have a link to your welder's owner's manual?

Thurman

"with plug in welding machine at 120 volt." Now a bell rings! Are you using an ARC welder (using electrodes) at 120 volts, or are you using a MIG (wire feed) welder at 120 volts? I'll never say you cannot be shocked with using a MIG welder, but the chances are less than an ARC welder. Actually, I've only seen one (1) 120 volt ARC welder in my life and it was not a good one. IF you are using a MIG welder, are you using one with or without shielding gas(es)? You stated YOU have limited workspace, so this is important. You DO NOT want to be using a MIG welder with shielding gas in an enclosed area that you MAY even stick your head into or very close to. These inert gases will deplete the oxygen/breathing air supply, like very quick. IF you are using a MIG welder with flux-cored wire, it's probably worse. The stuff in the coating of the wire is a strange mixture of chemicals to aid in the metal bonding of wire and base metal. Maybe I'm ranting on too long, buy maybe not--I've been around welding too long and seen others pass out from small mistakes.. Please be careful, Good Luck, David

Yoyizit

The voltage is substantially lower with the MIG but with wet hands you could be in serious trouble in either case.