# Dividing Head Welding Positioner Ground Lug Ideas



## Ironken (Jul 27, 2017)

O.K. guys. Matt at PM gave me a good deal on this incomplete dividing head and it's on its way. I will be ordering a 5" or 6" 3 jaw chuck and backing plate for said dividing head. If you look in the pic and notice the degree ring and the brass pointer mounting screw, this is what I want to fabricate a ground to.

The degrees will get machined off of the ring and I want to use a copper "brush" radiused to ride on the old degree ring using the mounting screw for the pointer. I need to come up with simple ideas to keep a bit of pressure on the copper brush to ensure contact. A short lead will be bolted to this part to connect my ground clamp to......ideas? I was thinking a "leaf spring" type setup with a copper brush bolted to the end but, 1/16 +/-  spring steel is hard to find.

I have a dc worm drive motor, #25 chain and small sprockets along with a reversable speed controller on hand.


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## Bob Korves (Jul 27, 2017)

Use it as a dividing head as it was designed for, and make a simple motorized turntable for welding.  My $.0.02, and worth every penny.  Lots of people on this site could use a good dividing head like that one.


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## Ironken (Jul 28, 2017)

Bob Korves said:


> Use it as a dividing head as it was designed for, and make a simple motorized turntable for welding.  My $.0.02, and worth every penny.  Lots of people on this site could use a good dividing head like that one.



You're kidding right....? Lotsa people could have purchased this very item but I did, to use for my purpose. Usually Bob, you add a huge amount of solid advice to a thread that I respect. This time....not so much. My query was for ideas on a grounding mechanism that may be better than my own. This forum is dripping with great ideas, thus my post.

I can easily build "a simple motorized turntable for welding" but, this dividing head fits the bill oh so well.

Soooo, got any ideas on how to ground this thing correctly?


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## Bob Korves (Jul 28, 2017)

Ironken said:


> You're kidding right....? Lotsa people could have purchased this very item but I did, to use for my purpose. Usually Bob, you add a huge amount of solid advice to a thread that I respect. This time....not so much. My query was for ideas on a grounding mechanism that may be better than my own. This forum is dripping with great ideas, thus my post.
> 
> I can easily build "a simple motorized turntable for welding" but, this dividing head fits the bill oh so well.
> 
> Soooo, got any ideas on how to ground this thing correctly?


I respect that it is your dividing head and you can do whatever you want with it.  Unless the dividing head is no longer suitable for it's intended use, I respectfully disagree with re-purposing it as a welding table.  My opinion.  I won't comment on ideas for adding a ground to it.


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## Randall Marx (Jul 28, 2017)

Re-purposing the dividing head aside, I like the idea of using a copper brush to ground against a rotating disk. Brass would likely work about as well and can be had in brush form, already mounted to a metal shank (like a wire wheel for use in a drill for cleaning). If that could be used, you would already have a lug for clamping the ground clamp to it. Maybe mounted on a spring to hold pressure against the rotating disk (like you had described). I find this interesting as I have needed something similar before, but could not get the entire idea together at once.


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## RJSakowski (Jul 28, 2017)

I believe that by "copper brush", the OP is referring to the type of brushes used in automotive starters.  A wire brush most likely would not last very long as there would bve a tendency to burn the bristles.  I would suggest a set of four brushes, on spring loaded pivots to contact the ring.  The ring itself should be copper or brass and the brushes could be copper impregnated graphite.  This sort of contacts has been used for automotive starter motors and a salvaged starter could be a quick way to accomplish your goal. At 1:31 into the following video, you see the brush setup.


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## Ironken (Jul 28, 2017)

Randall Marx said:


> Re-purposing the dividing head aside, I like the idea of using a copper brush to ground against a rotating disk. Brass would likely work about as well and can be had in brush form, already mounted to a metal shank (like a wire wheel for use in a drill for cleaning). If that could be used, you would already have a lug for clamping the ground clamp to it. Maybe mounted on a spring to hold pressure against the rotating disk (like you had described). I find this interesting as I have needed something similar before, but could not get the entire idea together at once.



Good idea. As RJ said, the amperage would be too high for the bristles though.


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## markba633csi (Jul 28, 2017)

I agree with Bob, seems like using a sledge to kill a mosquito but... RJ has the best idea, starter motor brushes and lots of them around the perimeter.
Me I would try to keep the dividing head functionality also, unless I already had another div head.
Mark
ps here's an idea: maybe fill the unit with graphite powder instead of oil then you wouldn't need brushes at all.


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## Buffalo20 (Jul 28, 2017)

Can I buy the divider parts, you not going to use?/


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## Ironken (Jul 28, 2017)

RJSakowski said:


> I believe that by "copper brush", the OP is referring to the type of brushes used in automotive starters.  A wire brush most likely would not last very long as there would bve a tendency to burn the bristles.  I would suggest a set of four brushes, on spring loaded pivots to contact the ring.  The ring itself should be copper or brass and the brushes could be copper impregnated graphite.  This sort of contacts has been used for automotive starter motors and a salvaged starter could be a quick way to accomplish your goal. At 1:31 into the following video, you see the brush setup.



Great idea, RJ! Thanks for clearing the details up for Randall.


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## Ironken (Jul 28, 2017)

Buffalo20 said:


> Can I buy the divider parts, you not going to use?/



Heck no, you can't buy them! You can have them free, though.

The dividing head in question is incomplete, you are welcome to any parts that I receive that are unused.....probably just the crank and plates. I will let you know what I have left over. It may be a few weeks.


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## Ironken (Jul 28, 2017)

markba633csi said:


> I agree with Bob, seems like using a sledge to kill a mosquito but... RJ has the best idea, starter motor brushes and lots of them around the perimeter.
> Me I would try to keep the dividing head functionality also, unless I already had another div head.
> Mark
> ps here's an idea: maybe fill the unit with graphite powder instead of oil then you wouldn't need brushes at all.



The graphite powder idea kinda threw me, kinda outside the box but cool. There are some huge positioners out there so it's not really overkill. Alot of guys are using a setup similar to this (just grounding thru the chassis and bearings....bad idea) and they work very well. I have a big set of turning rolls and need a bench top setup.


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## brino (Jul 28, 2017)

markba633csi said:


> maybe fill the unit with graphite powder instead of oil then you wouldn't need brushes at all.



Interesting idea, but I wondered if you'd end up with a big mass of sintered graphite inside........

What about turning this inside-out.......once you machine off the degree scale, drill a number of radial holes along the edge. In the holes put your brushes. Then get/find/make a (copper?) ring that sits on the outside perimeter of the disk, and mount it to the threaded hole with a bolt that connect to the welder ground. This ring could be bent round from a narrow strip.

This may make it easy to have multiple brushes to share the current (though their size is limited by the plate thickness), and they would be (at least partially) protected from spatter and grinding grit.

Other thoughts:
-you may need to experiment to find the best materials.....could you use just steel ball bearings as brushes?
-could the brush be a small spring and a tight "slip fit" copper rod, with a rounded outer end.
-I think I saw some bb-gun BB's with a copper coating, but I can't say how thick.....

Is there room inside the housing for the brushes? They could run on the back of the output plate.

-brino


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## RJSakowski (Jul 28, 2017)

Actually, I would look at insulating the dividing head from the work if at all possible.  Passing electric current through bearings is never a good idea.  When the currents can reach several hundred amps, even worse.  If it is not possible to isolate the work from the drive, at least bring the electrical connection in downstream from and rotating surfaces.

The Delco Remy brushes are capable of passing several hundred amps.  Since this is not a high rpm  application, you could beef up the brush pressure for more positive contact.


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## woodchucker (Jul 28, 2017)

RJSakowski said:


> Actually, I would look at insulating the dividing head from the work if at all possible.  Passing electric current through bearings is never a good idea.  When the currents can reach several hundred amps, even worse.  If it is not possible to isolate the work from the drive, at least bring the electrical connection in downstream from and rotating surfaces.
> 
> The Delco Remy brushes are capable of passing several hundred amps.  Since this is not a high rpm  application, you could beef up the brush pressure for more positive contact.



If the ground is on the faceplate, and the arc is on the piece, the shortest path never touches the bearings. So there shouldn't be a problem right?
I like the idea of using a braided copper wire as the brush, just cinch it up on the outer perimeter of the face plate. 
It does seem a shame to ruin a good divider, but it is yours.  I probably would have done it differently, and probably less expensively.


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## Ironken (Jul 28, 2017)

brino said:


> Interesting idea, but I wondered if you'd end up with a big mass of sintered graphite inside........
> 
> What about turning this inside-out.......once you machine off the degree scale, drill a number of radial holes along the edge. In the holes put your brushes. Then get/find/make a (copper?) ring that sits on the outside perimeter of the disk, and mount it to the threaded hole with a bolt that connect to the welder ground. This ring could be bent round from a narrow strip.
> 
> ...



Brino, thanks for taking time to put all of your ideas out there. The spring loaded copper rod riding on the degree plate is the one I like best.


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## Ironken (Jul 28, 2017)

RJSakowski said:


> Actually, I would look at insulating the dividing head from the work if at all possible.  Passing electric current through bearings is never a good idea.  When the currents can reach several hundred amps, even worse.  If it is not possible to isolate the work from the drive, at least bring the electrical connection in downstream from and rotating surfaces.
> 
> The Delco Remy brushes are capable of passing several hundred amps.  Since this is not a high rpm  application, you could beef up the brush pressure for more positive contact.



I'm looking into the starter brushes as well. Their current carrying capacity is high! Thank you.


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## Ironken (Jul 28, 2017)

woochucker said:


> If the ground is on the faceplate, and the arc is on the piece, the shortest path never touches the bearings. So there shouldn't be a problem right?
> I like the idea of using a braided copper wire as the brush, just cinch it up on the outer perimeter of the face plate.
> It does seem a shame to ruin a good divider, but it is yours.  I probably would have done it differently, and probably less expensively.



I thought about the braided copper wire but, I couldn't come up with an effecient way for it to follow the head when I pivot it horiz to vert......unless I turn a wider ring and wrap a spring loaded braided cable around it and a bracket to the body. Good idea Wood!

I only have $160 in this delivered. Could I build one as compact and clean for $160 that pivots horiz and vert with my time included? Probably not. I have side work lined up that pays way better than my own projects do.

To ease everybody's troubled mind on the torture of a good dividing head.....had I purchased a complete unit, it would have found a home on my mill. What kinda animal do you think I am? Holy crap at the negativity about this project. You woulda thought I was clubbing baby seals.....I stopped doing that years ago.


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## Wreck™Wreck (Jul 28, 2017)

If you ground to the housing the current will pass through the bearings, build a brush holder with spring loaded carbon or copper brushes that ride on the back plate.

I have built multi conductor slip rings in the past using stock brushes from McMaster, actually copper brushes would work fine in such a low speed application.

Good Luck


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## woodchucker (Jul 28, 2017)

Ironken said:


> To ease everybody's troubled mind on the torture of a good dividing head.....had I purchased a complete unit, it would have found a home on my mill. What kinda animal do you think I am? Holy crap at the negativity about this project. *You woulda thought I was clubbing baby seals.....I stopped doing that years ago.*


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## RandyM (Jul 28, 2017)

Ironken said:


> I thought about the braided copper wire but, I couldn't come up with an effecient way for it to follow the head when I pivot it horiz to vert......unless I turn a wider ring and wrap a spring loaded braided cable around it and a bracket to the body. Good idea Wood!
> 
> I only have $160 in this delivered. Could I build one as compact and clean for $160 that pivots horiz and vert with my time included? Probably not. I have side work lined up that pays way better than my own projects do.
> 
> *To ease everybody's troubled mind on the torture of a good dividing head.....had I purchased a complete unit, it would have found a home on my mill. What kinda animal do you think I am? Holy crap at the negativity about this project. You woulda thought I was clubbing baby seals.....I stopped doing that years ago*.



I still like you Ironken. 

But in all fairness, you knew it was coming.

I just think it is great that it didn't become scrap.


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## Bob Korves (Jul 28, 2017)

Tail between legs.  I did not see the word "incomplete" in your original post, and I read it twice.  My bad.  Very kind of you to offer the leftover parts to Buffalo20.


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## Ironken (Jul 28, 2017)

Wreck™Wreck said:


> If you ground to the housing the current will pass through the bearings, build a brush holder with spring loaded carbon or copper brushes that ride on the back plate.
> 
> I have built multi conductor slip rings in the past using stock brushes from McMaster, actually copper brushes would work fine in such a low speed application.
> 
> Good Luck



Good info with personal experience! Thank you.


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## Ironken (Jul 28, 2017)

RandyM said:


> I still like you Ironken.
> 
> But in all fairness, you knew it was coming.
> 
> I just think it is great that it didn't become scrap.



Thanks Randy, one less pitchfork and torch that I have to worry about showing up on my doorstep...lol


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## Ironken (Jul 28, 2017)

Bob Korves said:


> Tail between legs.  I did not see the word "incomplete" in your original post, and I read it twice.  My bad.  Very kind of you to offer the leftover parts to Buffalo20.



You did not see it because it was not there. I edited my post to add "incomplete". I figured it would reduce the future flaming. Its all good.


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## Silverbullet (Jul 28, 2017)

I'm not sure how but I would try to figure out another way to spin for welding . An old table saw trunion with a gear reducer motor set up. It's just that precision tools are for precision work tight tolerance , welding will ruin it quickly any splatter gets to any sliding surfaces it won't work for welding long in my opinion. It's yours to do as you please good luck I hope it does well .

Ok I didn't know it was a China junk , do your best have fun. Try using a carbon brush spring loaded ,like the motor brushes. Bigger the better just polish the plate for contact. It will work well if you use spray graphite on the moving parts it will increased conductivity.


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## markba633csi (Jul 29, 2017)

Also realize folks that this is an imported dividing head and not a vintage Brown and Sharpe or Ellis.  Club away!


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## Wreck™Wreck (Jul 29, 2017)

Bloody hell just did a search for "cheap rotary table", one may buy a "new" 4"  table for $59.00 + $19.00 freight. I would buy 4 of them  and weld away, if one lasts 2 months  then fails just replace it, if you get 2 years of work for $300.00 it is well worth it. They also have T-Slots which allows mounting most any kind of fixture you may have to make.


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## Ironken (Jul 29, 2017)

Silverbullet said:


> I'm not sure how but I would try to figure out another way to spin for welding . An old table saw trunion with a gear reducer motor set up. It's just that precision tools are for precision work tight tolerance , welding will ruin it quickly any splatter gets to any sliding surfaces it won't work for welding long in my opinion. It's yours to do as you please good luck I hope it does well .
> 
> Ok I didn't know it was a China junk , do your best have fun. Try using a carbon brush spring loaded ,like the motor brushes. Bigger the better just polish the plate for contact. It will work well if you use spray graphite on the moving parts it will increased conductivity.



Good ideas.....never thought about spray graphite.


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## Ironken (Jul 29, 2017)

Wreck™Wreck said:


> Bloody hell just did a search for "cheap rotary table", one may buy a "new" 4"  table for $59.00 + $19.00 freight. I would buy 4 of them  and weld away, if one lasts 2 months  then fails just replace it, if you get 2 years of work for $300.00 it is well worth it. They also have T-Slots which allows mounting most any kind of fixture you may have to make.



I seen those rotary tables too. Problem is the angle of the dangle on the crank wont work well with my worm drive motor when I flip the table vertical. Too bad or I would do exactly as you said. When I was done with it, I could throw that at a baby seal and save my clubs.


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## markba633csi (Jul 29, 2017)

I just assumed it was an import head and not a priceless hair-loom
Mark


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## 4GSR (Jul 29, 2017)

markba633csi said:


> Also realize folks that this is an imported dividing head and not a vintage Brown and Sharpe or Ellis.  Club away!


Still a dividing head!!!

Wait!!! IT was a dividing head


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## f350ca (Jul 29, 2017)

I've been passing the ground through the body of a gear reducer I use as a welding  positioner for years. I use it for mig, tig and occasionally for the plasma cutter. Still seams fine.

Greg


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## Ironken (Jul 29, 2017)

f350ca said:


> I've been passing the ground through the body of a gear reducer I use as a welding  positioner for years. I use it for mig, tig and occasionally for the plasma cutter. Still seams fine.
> 
> Greg



Good to know....thank you.


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## Ironken (Jul 29, 2017)

markba633csi said:


> I just assumed it was an import head and not a priceless hair-loom
> Mark






Im like the villian in Toy Story. Destroying good toys and making people sad.

I'm going to set up a gofundme page called "savethedividinghead" with a small donation YOU can save this innocent tool from the clutches of the diabolical Ironken.


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## Ironken (Aug 5, 2017)

Well boys, this is what I came up with. Thanks to all for the input!


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## Wreck™Wreck (Aug 5, 2017)

Excellent, Slayer of Cheap Tools.
That should work fine for you if slow enough.


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## Ironken (Aug 5, 2017)

Wreck™Wreck said:


> Excellent, Slayer of Cheap Tools.
> That should work fine for you if slow enough.



Thank you! My cheap tool butcher shop thanks you as well.....lol

Speed is .5 rpm to 3 rpm. I still need to find a 6-8" 1-1/2x8 threaded faceplate and a 5" 3 jaw el cheapo chuck and back plate.


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## markba633csi (Aug 5, 2017)

That copper chunk should be good for a couple hundred amps no problem
Mark


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## Ironken (Aug 5, 2017)

markba633csi said:


> That copper chunk should be good for a couple hundred amps no problem
> Mark



I think the copper will handle way more current than the little work lead I have on it. I have a 1/0 for it if I need to pour the smoke to it.


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## Ironken (Sep 10, 2017)

Well boys....this is what I came up with. As you see, it turns a bit slow for MIG on 5/8. I did have the machine running hot and fast though. It even has a foot pedal switch.

My next stunt is a Noga knockoff mag base with a clamp that will accomodate my MIG and TIG torches. I have a remote contactor switch in the works for a hand switch on my MIG machines. Hit the foot pedal and click the switch and burn. The TIG will remain foot controlled. If the base setup works well, I may throw them on ebay.


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