How The Heck Did That Happen

I've got a decent if not great welding table in my shop. Basically a frame work of 2x2x1/8 inch steel tube with a 1/4 steel plate for the
top. Often when working on relatively clean pieces that I have to turn and rotate I'll just attach the work piece clamp to the table top and do what I need to do. It usually just works.
Yesterday I was making (its not finished yet) a 3PT to hitch assembly to use on John Deere tractor. Something to I can drop in the quick hitch to quickly and easily more trailers around. I am using whatever scraps and drops I have around. For now I am just grinding and v-grinding enough to get a good weld. Because its drops and scrap some is cover in paint and others are covered in old paint or powder coat. I had been clamping direct to good surfaces on the work piece prior to taking it out for a test fit.
Even I was able to lay down welds that didn't look completely terrible. Mostly 1/4 wall tube salvaged from a trailer axle, and solid round bar for all the pins. I had the welder set for 3/8 and it was just doing a dandy job in spite of my low skill level.
When I came back in to weld the upper cross pin in place I was still amazed with how well the beads were laying down. Then I paused and realized I had not reattached the clamp to the work piece. I looked around expecting to see it clamped to the table. No, it was laying on the floor. My brain short circuited for a moment. I'd just started a weld bead and was half way around the pin when I stopped. It looked ever bit as not totally terrible as every other weld. How was that possible? Ok, steel table (to heavy to lift) directly on a concrete floor. I just stood there for a moment waiting for my brain to catch up with my vision. The clamp might have been touching a piece of stainless angle that might have been touching a piece of stainless plate that might have been touching one leg of the table. Maybe. Just barely.
When I tried to move the hitch I found it had welded itself to the table. I don't mean firmly, but enough that I had to break it loose and there were a couple pits in the table top.
They always told me when you crank up up the juice the welds often get easier, but I never thought it would be so easy you didn't even have to attach the work piece clamp. LOL.
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On Sat, 23 Oct 2021 14:06:54 -0700, Bob La Londe wrote:

Sounds like you have an unintended return path for your welding current. If this path includes your welder power ground, as can happen if the welder return connection and the table are separately connected to your power distribution safety ground, then you are at risk of melting the welder safety ground conductor and/or starting a fire since welding machine output current can be much greater than welder input conductor current rating, suggest you check it out.
Glen
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On 10/23/2021 2:23 PM, Glen Walpert wrote:

Did the easiest test. Hung the work piece clamp on the welder. No arc on the table. I knew it wouldn't. Its not an old beat up POS welder that's been patched and repaired. Its an old rarely used decent name brand welder that looks almost new except were I have written notes on it with a paint marker. Still I did a test anyway.
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On 11/14/2021 6:34 AM, amdx wrote:













I would generally agree, but the work piece had minor autogenous welds to the table top. Like the arcing of a dry contact that has no protection. maybe that was purely incidental. I do not normally see that.
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"Bob La Londe" wrote in message
On 11/14/2021 6:34 AM, amdx wrote:

I would generally agree, but the work piece had minor autogenous welds to the table top. Like the arcing of a dry contact that has no protection. maybe that was purely incidental. I do not normally see that.
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Maybe the clamp was lying on the table until you stopped welding and knocked it off by moving the cables.
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On 11/17/2021 4:59 AM, Jim Wilkins wrote:











Maybe. I certainly suffered a moment of cognitive dissonance when I lifted my hood and saw the work piece clamp laying on the floor.
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"Bob La Londe" wrote in message

Maybe. I certainly suffered a moment of cognitive dissonance when I lifted my hood and saw the work piece clamp laying on the floor.
-----------------
You missed your chance to be a billionaire ray gun inventor.
-Tony Stark
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On 11/20/2021 10:18 AM, Jim Wilkins wrote:














Ray guns already exist. All I could do is refine them. In the past atmospheric conditions and power requirements limited their effectiveness and practicality.
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