welding on a lathe

[camdigger]

With all those wonderful welding tables I see around, why would you weld in a lathe?

Alignment. To be clear, Kurtis at CEE only tacks in the lathe before removing to use a welding positioner.

Kurtis has addressed his welding in the lathe. Even he recommends caution.

[Black Forest]

My rotary welding positioner has a braided ground strap over the shaft that attaches to the chuck. This shaft runs through the bearings. If I have to weld on my lathe which I have done quite often I used a braided ground strap also.

[JRouche]

I was just watching some youtube stuff and in doing so I noticed I have yet to see someone hook up the ground clamp to the work piece that they had chucked in the lathe and they just start welding. Now I hope they dont just have the ground clamp hooked on the leg of the lathe. Being a welder in the oilfield I wondered about that.

Sounds like a welding positioner to me.

A gentleman here gave me a very nice DC motor and controller for my welding positioner. It works.. I had to figure out the leads.

Also it can work as a crude lathe. In horizontal mode with a tail stock I guess "_

Its a horizontal table now for tig welding.. JR

[Jammer Six]

such as? when I've done it, I've covered all critical surfaces(chuck, ways, leadscrew, ect) with heavy leather & had a robust ground lead making good contact with the workpiece, what am I risking damaging?

Apparently, both your reputation and your good name here, on one-in-one-of-millions-of-constellations-of online forums.

[mtraven]

You can do a lot of damage to other parts of the machine even if you try to protect it.

such as? when I've done it, I've covered all critical surfaces(chuck, ways, leadscrew, ect) with heavy leather & had a robust ground lead making good contact with the workpiece, what am I risking damaging?

Modern lathes are full of contactors, relays, microswitches ---- things that wouldn't take kindly to a burst of high amperage current in the system, I think.....

which is why its so important to control the electrical pathways.

[Video Man]

Modern lathes are full of contactors, relays, microswitches ---- things that wouldn't take kindly to a burst of high amperage current in the system, I think.....

[JoeLee]

but thats what matters. you know the problem is: running current across ball bearings can cause damage by arcing, right? So you deal with that, you protect you're ways & chuck / spindle from splatter and you're fine.

that being said, I'd still rather weld on a positioner or an old lathe.

I under stand the problem with pulling ground through the bearings but that wasn't my point.
You can do a lot of damage to other parts of the machine even if you try to protect it.

JL...............

[mtraven]

The way I see it if a person has such little regard for his lathe that he's welding on it it doesn't make any difference where he pulls ground from.

JL.....

but thats what matters. you know the problem is: running current across ball bearings can cause damage by arcing, right? So you deal with that, you protect you're ways & chuck / spindle from splatter and you're fine.

that being said, I'd still rather weld on a positioner or an old lathe.

[Jim Stewart]

I am pretty sure he used his "beater" lathe for that.

I think you're right. Don't recall his ever mentioning grounding.

-js

[J Tiers]

I am pretty sure he used his "beater" lathe for that.

[Jim Stewart]

The way I see it if a person has such little regard for his lathe that he's welding on it it doesn't make any difference where he pulls ground from.

JL.....

Sir John welded damaged motor shafts in a lathe. Don't recall how he grounded the workpiece, though...

-js

[JoeLee]

The way I see it if a person has such little regard for his lathe that he's welding on it it doesn't make any difference where he pulls ground from.

JL.....

[mtraven]

I dont understand the " you gotta do what ya gotta do" mentality in this particular case. If ya gotta weld on the lathe, fine, just do it right. ground the workpiece, simple enough, there's just no need to sacrifice a machine as was the case in the 10EE uranium mill example (presumably, now too radioactive for any one to touch?).


and isn't part of "what ya gotta do," using the machine for future work? it is in my shop.


edit / add

i dont have or know anything of VFD's, but someone brought them up & I have -some- knowledge of electrics. only real electrical pathway is ground, hard to imagine that causing any problems for your VFD. but I'm happy to be proved wrong my someone who actually know what they are talking about

[The Artful Bodger]

Nothing about lathes.... ten or so years ago we had a major earthquake in New Zealand, a city was badly damaged, railroad tracks torn aside and roads displaced one for lane-width sideways but this is about a milking shed with a rotating turntable that carried 50 cows at a time.

The earthquake buckled the turntable so that it would not longer run on it's peripheral rollers. Crowbars, jacks ropes etc were to no avail as the entire structure was just too springy. Until one guy who was not even involved in the repair asked if he could try. OK, he collected three or four arc welder and boxes of electrodes, he had people lay down beads where he had marked the turn table in several places and after a while called a halt. Everyone watched and waited until a mighty 'twang' was heard and the turntable jumped and fell into its proper track.

[reggie_obe]

The 10ee's that machined the Uranium pretty much were sacrificed.

They were chosen and purchased because they needed the precision of the 10EE and production use wasn't a one-off part or a shafting weld buildup.