How to properly ground when welding

Question

I read several articles online about grounding when welding and I'm more confused than when I started. I have an AC welder (old Lincoln buzz box)...just in case the type matters (AC vs DC). Here are the salient points (I think):

• The welding machine itself should be grounded. Mine has a ground pin on the plug and a properly grounded receptacle, so this is covered.
• A grounding clamp must be connected to ground (e.g. grounding rods, ground bar in panel). The wire that connects the grounding clamp to ground should be large (e.g. 4-8 AWG).
• When welding, the return electrode and ground clamp should be clamped on whatever you are welding. If using a welding table, then both clamps should be on whatever is being welded, if possible, otherwise you can clamp both onto the table.

The last bullet is where things get confusing. Is that right, or should the return electrode always be on whatever is being welded and the grounding clamp always on the bench (if using a bench)?

Answer 1

The return electrode needs to be electrically connected to whatever you are welding.

Connecting it directly to the item being welded is best.

If you connect it to the table, then the connection between the table and the item being welded would have to be good, and it usually isn't.

The bit you have quoted specifically says that both clamps (you appear to be looking at something that involves whole extra "grounding" clamp from your second bullet point I never had or used in 5 credits of welding classes) should preferably be on the item being welded, directly. You could, of course, make up a set of connectors to bond them to the table as well, if using a table, and then have the work clamps on the work, if that would make you happier for some reason.

Neither my welding machine's instructions nor any of my welding class material feel that a separate grounding clamp is called for at all - just the return electrode, and a properly grounded machine.