# Dividing head or rotary table with plates?



## Larry42 (Feb 5, 2019)

I'm, retired & relatively new to machining and would like to add the ability to make gears and other things requiring accurate indexing. 
At this time I don't see any need for me to be able to tilt the work at other than the horizontal or vertical that the rotary table gives. A rotary table seems much easier to mount flat work to but I suspect that the "semi universal indexing head" can have the chuck removed and a plate added for flat work clamping.
At this point I'm inclined to buy the H/V rotary table with dividing plates & tail stock. Add a 6" 3 jaw or 8" 4 jaw chuck and be able to do most things that the "semi-universal indexing head" can do. What are the pros & cons?? 
My mill is a well used Jet 9x49 variable speed. Lathe is a 1440.  While most things I make are relatively small I do some repairs and have in the past regretted not getting tools to do larger, heavier work. Which brings me to rotary table sizes. 6" or 8"?? The 8" RTs are fairly heavy, but the size I'm considering.  I'll just move the vice down some and be able to mount the RT W/O needing to remove the vice. Maybe even let it ride along, as long as it doesn't interfere with other things.


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## pstemari (Feb 5, 2019)

TTBOMK dividing heads are generally intended for holding work at a static angle for cutting, while today tables are intended for moving the work during a cut to form an arc.

The exception to that is a universal dividing head with an attachment to drive off the milling machine power feed. That can be used for milling helixes.

Sent from my Pixel XL using Tapatalk


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## Mitch Alsup (Feb 5, 2019)




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## benmychree (Feb 5, 2019)

So far as size is concerned, bigger is better, in my opinion.  The larger swing allows larger work to be done.  Does the dividing head you are looking at have the capability of disengaging the worm?  The term Semi Universal infers that it does, and it is handy to be able to do so for direct indexing and indicating work in.


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## talvare (Feb 5, 2019)

I have a BP mill with the 9x48 table and use a 10" RT. I find that the work envelope on the RT gets used up pretty quickly with work holding devices which really limits the size of the work. If I were you, I'd seriously consider a 10" or 12" RT.
Just my .02 cents.
Ted


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## benmychree (Feb 5, 2019)

Ideally, a person should have both a rotary table and a dividing head; having said that, I find myself using the dividing head frequently and the rotary table seldom makes its way off the bench where it lives.


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## Bob Korves (Feb 5, 2019)

I have an 8" Rutland horizontal/vertical RT made in Taiwan that is about all I want to carry around without mechanical help.  It has done all I ask of it, and a larger fixture plate mounted to the top of the table could be up to any diameter I care to make it.  It is a high quality RT, and I am happy with it.  Just went out and weighed it on a bathroom scale, said ~55 pounds.  I also recently picked up a beautiful old adjustable height tailstock for it.  It is also very heavy and solid, maybe 25 pounds. 

I also have a 6" swing dividing head (no maker's mark, WWII?) with two sets of three dividing plates, two D.E. Whiton 1-3/4"  8 tpi mount chucks (3 and 4 jaw, also marked Rivett!}, and #9 B&S spindle tooling for it as well, and a mill mounting table adapter plate that holds the dividing head and the tailstock to it for quick mounting to the mill table.  Throw it on the mill, tighten 4 bolts, and it is ready to use, with less than .001" tolerance fit everywhere.

Given the choice between dividing head and rotary table, I vote for both!  The jobs they do are mostly quite different, and one does not work for the other very well.  In a pinch, yes, it can be done.


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## cathead (Feb 5, 2019)

Some years ago, I was having the same thoughts on what to buy and ended up getting a 12 inch Phase II VH rotary table. 
I have made many gears with it with no difficulty as well as the standard uses for a rotary table.  It's only drawback is
that it weighs close to 200 pounds so use a chain fall hoist to move it around.  I think most of the rotary tables are 90-1 ratio
so each rotation of the handle is 4 degrees on the plate.  At least mine is.  Sometimes it takes a bit of cogitating to figure out
which hole plate to use when making gears.  That part might be easier on a dividing head, not sure about that...

All in all, I'm happy with just a rotary table.


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## Shootymacshootface (Feb 5, 2019)

I cut these grooves with my 10" phase 2 rt. It's half of the clutch for the down feed on my mill. There are 50 teeth and it fit perfectly. Just had to do some math.


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## Larry42 (Feb 7, 2019)

I've watched the videos of the RT being used to machine curves while in the horizontal position. Joe pie has an excellent one. I'd also like to know how well it works for machining gears or splines in the vertical position (with a tailstock.) I've come to conclude that I would prefer the 8" in spite of it's wt. It appears the use of the dividing plates is much the same on the RT as on the dividing head. I should be able to mount the work using dead centers and a lathe dog and not need a chuck. Comments?


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## Larry42 (Feb 7, 2019)

Cat, how do you like your casting foundry, what do you cast? 
Shooty, nice work on that part. What steel did you use? Heat treat?


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## Shootymacshootface (Feb 7, 2019)

Larry42 said:


> Cat, how do you like your casting foundry, what do you cast?
> Shooty, nice work on that part. What steel did you use? Heat treat?


I think I made that out of a hydraulic cylinder rod without any heat treating. The original part broke in half, so I would say it was too hard.
If you can't make up your mind I would get a RT and use it to it's full potential, and then decide if you need a dividing head.


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## cathead (Feb 8, 2019)

Larry42 said:


> Cat, how do you like your casting foundry, what do you cast?
> 
> Casting is great fun.  I have made gear blanks made of aluminum and brass,  Also have made flywheels and faceplates for disc sanders.
> Also have made bearing blocks and also pistons.  I plan to move my casting operation to my new shop area this spring.  One is only
> ...


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## Janderso (Feb 8, 2019)

Nice work.
Did you turn your rotary table 7.2 degrees, make a cut, turn 7.2 degrees.......????


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## cathead (Feb 8, 2019)

Janderso said:


> Nice work.
> Did you turn your rotary table 7.2 degrees, make a cut, turn 7.2 degrees.......????



That is that one would do to make a 50 tooth gear.  I used a dividing plate on the RT crank for accuracy.
	

		
			
		

		
	



This is a home made dividing head plate I use on my rotary table.  The part in my hand is factory
plastic and the one on the plate I made of steel, way better...


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## Janderso (Feb 8, 2019)

I was picturing the method I described. When you got to the 48th or 49th cut, hmmmm.
It would be off.
Your method is much better.


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## cathead (Feb 8, 2019)

Janderso said:


> I was picturing the method I described. When you got to the 48th or 49th cut, hmmmm.
> It would be off.
> Your method is much better.



On a 90 to 1 rotary table, 1 rotation of the crank is 4 degrees.  So you make one full rotation plus the amount of holes
needed on the plate to advance 3.2 more degrees.


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## Janderso (Feb 8, 2019)

I recently purchased a very nice old used 10" rotary table. I have a 4" Bison chuck that went through the fire but, with a lot of work, it came out very good.
 I'll never use it in a lathe other than slow speed.
I thought it would be perfect for the RT.
On my want list, is a universal dividing head with tail stock.
The list is long.
I admire your abilities, that part you made for your mill is great!!


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## Shootymacshootface (Feb 8, 2019)

Janderso said:


> Nice work.
> Did you turn your rotary table 7.2 degrees, make a cut, turn 7.2 degrees.......????


Yes, that is exactly what I did. The first and last tooth was undetectable when it was finished.


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## Janderso (Feb 8, 2019)

Really, I was not sure you could get that accurate with an RT.


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## Shootymacshootface (Feb 8, 2019)

Janderso said:


> Really, I was not sure you could get that accurate with an RT.


There are no tolerance stacking errors if you stick to the math, 7.2, 14.4, 21.6, and so on.


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## Janderso (Feb 8, 2019)

Ah, OK, I was thinking you would count 7.2 each turn, I can see room for error.
That's great! I watched Joe Pie's recent videos on setting up and using the RT.
I must admit, I got lost. I am the kind of guy that has to do it.
Hands on, I'll learn. Seeing what you did gives me confidence to venture out and start using it with the chuck.
I need to make the sacrificial mounting table for the RT. I also need to start using the Noga spindle mount indicator holder I got.
The RT has a straight shaft, no taper. Adds mounting options IMHO.


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## Shootymacshootface (Feb 8, 2019)

Jeff, it's good to see you up and running again.


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## Larry42 (Feb 8, 2019)

Cat, I cast outside, only. Firing with propane in a home made furnace. It won't get hot enough to melt copper. I have a #11 graphite crucible (11# of aluminum capacity.) I've been watching the videos by olfoundryman, very good. My mold making has gotten better but still have some oopses. All the aluminum I use is scrap. I've found that extrusion AL machines really poorly, sticky! The best is automotive castings, probably a wide variety of alloys but all designed for casting. I've started using a commercial degassing chemical, now get less hydrogen bubbles.


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## Larry42 (Feb 8, 2019)

"I watched Joe Pie's recent videos on setting up and using the RT.
I must admit, I got lost."
Joe Pie has great videos, You just need to brush up on your geometry and trig to better understand them. The Machinist Handbook has a great section on math.


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