What exactly does this "welding positioner" do???

Weld positioners are motorized turntables / chucks that are adjustable speed, foot pedal controlled and allow one to weld continuously around the circumference of a round item like a pipe. What you have doesn't really look like a pipe beveling machine either, it looks more like something made up for perhaps a brazing operation where the operator just adds the brazing filler.

In my experiences, a welding positioner is for holding large pieces in a good welding position, say flat versus overhead to get the best possible weld, and sometimes rotating the workpiece as the weldor controls the foot pedal. Most looked like big robots with a drill press clamp table.

But, I have seen bevelers that will cut a saddle or branch by just entering some info. Today, that probably would be on a digital pad. The torch then cuts out the pipe so that the remaining piece can be teed or saddled or branched with minimal trimming. You can buy WrapAround CurveOMarks in templates that you wrap around a pipe and mark with soapstone, then cut. But you have to be good to bevel the pipe at the proper angle all along the cut.

They are sure fun to watch, and even funner to use, as it simplifies cutting with WrapArounds that in many cases you home made.

HTH

Steve

Just about any variable speed drive can be used to rotate objects for welding.. But, the motor, bearings and drive controller need to be electrically isolated from the electric welding supply and workpiece(s), whereas for a gas torch, isolation isn't an issue.

Might be -- or it might be for simply cutting pipe to length with the torch.

I would not. The arc welding is likely to kill the bearings that the chuck spindle turns in -- and perhaps the gears in the gearmotor as well. Only if you can insulate the workpiece from the chuck and spindle, and connect directly to the pipe will the bearings be likely to live a long life.

Enjoy, DoN.

I believe that is for beveling pipe weld test pieces for a training program. It looks home built.

Yes you could use it as a weld positioner as long as you don't ground through the motor or any bearings.

I don't think you would get much for the torch

I brought it home and it even works.

I know what I will do with it:

I will probably reuse or sell the acetylene machine torch.

The box itself I will use for a pig roaster. My first task would be to gear it down (change sprockets or gearmotor) some more, to get to 1 RPM speed.

i

Your neighbors are going to love that in your neighborhood. "We have this Russian guy down the street...he roasts whole pigs in his back yard...at least, we think they're pigs..."

Keep the O/A torch for a nice skin crisping finish to the roasting...

I'll bet the unit is fairly close to 1 rpm or even less. Looks like it was set up for doing pipe nipples, 6" pipe at 1 rpm would be 20" per minute.

You might check the duty cycle and power rating of the motor. What worked fine for a small, balanced load for 1 minute at time might not work so well for a much larger, unbalanced load for hours on end.

What unbalanced load? I'm sure Iggy's BBQ spit design will have ball bearings and adjustable counterweights along with a clutch to disengage the motor so you can free turn the spit during balancing.

This unit does 20 RPM at the highest. I am not too worried. I have a slower and larger gearmotor, or I can replace the 1:1 chain drive with different sized sprockets, some gearing or whatever. What attracts me here is that there is housing, shaft mount, chuck etc, stuff that always is a PITA to fabricate.

I think that if I slow 20 RPM 3.5 times by changing over gear sprockets, and run it at 1/5 of the speed, I will have the perfect RPM and sufficient torque. Even now, at 1:1 sprocket ratio, at 1/5 of the speed, I have to make an effort to stop the chuck with my hands.

The motor is continuous duty, 1/30 HP. I would expect it to be able to turn a pig at 1 RPM just fine.

Does it make any sense?

i

I am not sure about the clutch, but for sure I will use ball bearings.

i

Aren't you supposed to sear it first, to "lock in" the juices?

Thanks, Rich

My smaller (rated for 3 or 4 pounds of meat) rotisseries turn at 6 rpm.

1 rpm for a 70 pound pig sounds about right. But you need to have the motor running full speed to make the 1/30 hp so all the speed reduction has to be in the chains and gears, you can't do it with the speed control.

Bearings are not a huge issue, you could get along just fine with some bronze bushing bearings. In fact, bushings might be better about the heat and smoke environment.

The biggest problem I've run into with my smaller units is getting the load balanced. You can hear the motor and gears load up on one side, then a big flop as things flip to the other side. This flop loosens the meat on the spit as well as loosening up the drive. A lot of times there is just one logical place to run the main skewer through, you have to deal with the off center load in other ways.

Hence my suggestion for adjustable balance weights in the spit mechanism...

I agree about the bushings. You're not going to want normal ball bearing lubricant on your spit, either. A little lard or bacon fat will do at 1 rpm. You need a way to easily get the loaded spit in the bearings. Maybe split bushings in clamshell housings with slip on journals for the spit. I did something like that for a web takeoff. Then the dumbass safety inspector said the my clamshells were pinch hazards, so I fitted tiny 9/16" id hydraulic cylinders with speed control valves and 2 oz. reservoirs. They were cute.

Pete Keillor