# Dividing heads reviews & opinions?



## Argonavis (Jun 30, 2014)

Hello,

I've been thinking of picking up a dividing head in the fullness of time, and would be extremely grateful for any reviews that members might have of their units, or opinions regarding desired features, things to look out for, good brands, etc.  I'm particularly fond of the older home-grown brands, but that bias is not founded on any personal experience with these gizmos.

What brands are worthy of consideration?  Cinncinnati, Van Norman, B&S, Hardinge, etc?  What variety of gear ratios are out there beyond the common 40:1 ratio, and what are their virtues?  What size dividing heads make sense for a mid-size knee mill? How interchangeable are the plates for various different brands which might make them easier to find for sale?  What questions should I be asking?

Thanks for the time!

Hannes.


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## Frank Ford (Jun 30, 2014)

I have a Hardinge dividing head, and really like it -  super heavy and substantial, and with a 4:1 ratio, there's little or no counting turns.  I'm lousy at counting turns, so that's a big plus for me.


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## Senna (Jun 30, 2014)

The older American dividing heads are stout, acceptably accurate, and generally workhorse units.

In the used American iron you'll likely see brands like Carroll, L-W, B&S, Ellis, K-T, Cincinnati, and VN.
Personally I'd stay away from the oldest examples of any of them. 
I'd also discount those heads primarily meant to be powered from the table feed gearbox.
Obviously those dividing heads sold with extra plates, a tailstock and other accessories are worth more. How much more is debatable.

The universal type seem to me more versatile. At the possible expense of a tiny bit of accuracy.

 I don't know about plate interchangeability and also would like to know.

If you want finer accuracy the optical dividing heads offered by Leitz Wetzlar, Zeiss, and possibly others offer up to 2 arc second accuracy. And a scale which never wears out.  
In true Teutonic fashion you get superb engineering superbly constructed but often with Holy Cow complexity!
Very very cool devices and the engineering and accuracy appeal to me whether I can utilize that accuracy or not.

If you watch long enough you can grab a very good deal on normally expensive dividing heads of all makes.
Today I took delivery of a very nice Leitz courtesy of one of those very good deals.
Be patient and you'll see bargains pop up. 

Good luck in your search.


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## Senna (Jul 1, 2014)

8000 members and two dividing heads amongst us?

There must be more dividing head owners out there than the two who've responded.


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## COMachinist (Jul 2, 2014)

Hi
Well I don't have a dividing head per say but I do have a vertical/horizontal rotary table that has dividing plates and a 5" 4 jaw independent Chuck. I know it is china made but it is on par of a Phase II table. The worm screw has double bearings and the screw is submerged in an oil bath. It is a 90:1 and is very smooth. I has MT2 center which fits all my lathe tail stock tooling. and it is a very good size for my Bench top mill. With the 4 jaw you can get the run out really down to sub .001. I'm very happy with it. I find it more useful than a dividing head by far.
Happy Machining, and Fare Thee Well
CH


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## chuckorlando (Jul 2, 2014)

I have used an old b&s a few times at school.  Worked awesome, smooth and easy to use. I'll be going the roto table with plates route as I cant afford both. Just to much height on the dividing heads to use like a roto table.


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## Senna (Jul 2, 2014)

chuckorlando said:


> I have used an old b&s a few times at school.  Worked awesome, smooth and easy to use. I'll be going the roto table with plates route as I cant afford both. *Just to much height on the dividing heads to use like a roto table*.



That is true and of particular concern if Z axis capacity is limited.

But, a universal dividing head makes it very easy to set up angles.

As I said earlier, if a guy is patient and persistent in his searching he can find a great RT AND a great DH for the price of a new Chinese RT.
I got arguably one of the finest dividing heads ever made, the Leitz, for under $500 including freight (~$250) from CA to MN.
I think I paid less than $150 shipped for the 10" Japanese made Kamakura RT I have too.
$650 out of pocket and I'll never need another RT or DH as long as I live.


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## chuckorlando (Jul 2, 2014)

I watch ebay and craigslist no less then 3 times a day just for a RT or DH. I buy deals best I can so if a DH came about with all I wanted for a price I have in my pocket right then, I'll take it. All it took for me was 8 flutes in a handle and I was sold. Then I seen Bill's handles with the graduations and it put dividing of one form or another at the top of my list.

At the end of the day I want and will have both. All it takes is money


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## Argonavis (Jul 3, 2014)

Thank you all for your comments!

In reference to Ken's comment regarding the length of the thread, is it that dividing heads are not a very popular accessory for hobby machinists?  In that case it might suggest that they'd be easier to find in "non-hobbyist" circles.

@Senna, you also said that you'd stay away from the oldest examples of the US units -- why?  Is it just that they've seen the most wear & tear, or do newer units have different features?  Are there any tells to help separate the older from the newer models?

With regard to the universal & semi-universal models -- I've seen some which pivot down from the horizontal perhaps 20 degrees and up about 80, thus making it impossible to mimic a rotab.  Is there a common range of motion for the arc that the universals can traverse?  It would seem to me to be enormously useful to be able to set the spindle into the vertical position.

@COMachinist, thank you for the images!  How are the dividing plates used/mounted with your rotab?  I've never seen dividing plates used with a rotab.

Would anyone have any guidance about what constitutes a "good" or a "reasonable" deal in a dividing head?  Or are there too many factors to make any useful generalizations?

Hannes.


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## awander (Jul 3, 2014)

I have an old Ellis dividing head that I picked up for less than $200 on ebay. It came with 3 plates, and a tailstock. It is a 40:1 ratio head. It can swivel from 15 degrees below horizontal to 100 degrees above horizontal. It has a 6-1/2" swing and weighs about 60 lbs.

The downside to the older heads like this one is they typically use no-longer-common tapers in the spindle. Mine is a B&S #9, and tooling for this is by no means as easy or inexpensive to get as a Morse taper.

I picked up a faceplate that threads onto the 1-3/4 - 8 spindle nose, and adapted it so that my 6" 3-jaw and 8" 4-jaw lathe chucks will fit.

I also picked up an old DA500 Collet chuck with a bunch of collets-that one had a B&S #10 shank, but I turned it down to fit the B&S #9.

I also modified the old Ellis to work under CNC control-I will say that I don't use it every day, but when I do, it sure is handy!


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## Senna (Jul 3, 2014)

Argonavis said:


> Thank you all for your comments!
> 
> In reference to Ken's comment regarding the length of the thread, is it that dividing heads are not a very popular accessory for hobby machinists?  In that case it might suggest that they'd be easier to find in "non-hobbyist" circles.
> 
> ...



Hannes,

The primary reason I'd stay away from the oldest examples is the wear and tear you mentioned. Also the oldest ones have some REALLY esoteric parts and many of the accessories shipped with the DH when new have been scattered to the four winds over the decades.

The oldest examples are usually easy to spot because they look strange.
Here's an old B&S which also has the feed shaft for driving from the table feedbox.
http://www.ebay.com/itm/MACHINIST-T...0?pt=BI_Tool_Work_Holding&hash=item2c7b54bea4

I wouldn't touch this one.

Most Universal DH's I've seen will rotate slightly past straight up.

You will definitely be better served in the industrial marketplace than in the hobbyist marketplace. Just so much more choice.

On eBay I'd be looking for true auctions with no reserve rather than the BIN listings. I'd look to sellers such as STM Surplus and HGR Auctions. Both have true auctions with very low starting prices. Occasionally these will yield fantastic bargains.
I'd also look at the HGR website. Sometimes, usually actually, HGR has great pricing. They're easy to deal with and shipping isn't bad.
My salesman there is Marshal Michaels. If you need to pick a salesman you could do worse than Marshal.


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## chuckorlando (Jul 3, 2014)

When I am looking I search "ending soonest" for auctions. Then once I get to 5hr or 8hr left in the listings I switch my search. I then look at "newly" listed and also switch to "buy it now" just in case a new one comes up for a deal. Gotta snatch it before anyone else see's it.

Yes roto tables can use dividing plates and tail stocks. Both tools have their pros. The table can use the chucks, plates, and tails stock just like a DH but dont do angles. Some do angles but they look rather flimsy to me so I dont pay much attention to those styles. But a RT can be layed down for rounding corners . A DH can lay down as well but they stick up so high they just aint the best tool for that. But as mentioned they can do all kinda angles and are built alot more solid in that department.
http://www.grizzly.com/products/6-Rotary-Table-w-Div-Plates/H7527
Heres a 6in grizzly table that  comes with plates and all for reference. I am not endorsing it


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## Stonebriar (Jul 3, 2014)

So let me ask a really stupid question.  What is the difference between a dividing head and a super spacer?

Rick


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## Marco Bernardini (Jul 3, 2014)

Stonebriar said:


> So let me ask a really stupid question.  What is the difference between a dividing head and a super spacer?
> 
> Rick



Generally a dividing head has plate full of holes (it's not a disc brake!!!) to help you to divide a circle into a precise number of parts without to have to calculate the angle.
See these three videos:
https://www.youtube.com/watch?v=pIg8InzUu3U
https://www.youtube.com/watch?v=MXV7eV_WNEI
https://www.youtube.com/watch?v=AUMFXPqCJVs

If you place an hex socket wrench into a vise and a bolt through a scrap of plywood you'll have the cheapest 2, 3 and 6 side dividing table.
With a 12-point socket wrench you can even have more partitions: 2, 3, 4, 6, 12 sides.


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## Senna (Jul 3, 2014)

chuckorlando said:


> When I am looking I search "ending soonest" for auctions. Then once I get to 5hr or 8hr left in the listings I switch my search. I then look at "newly" listed and also switch to "buy it now" just in case a new one comes up for a deal. Gotta snatch it before anyone else see's it.



That is the technique I use as well. The only thing I'll add is that sometimes the best auctions, from a buyer's POV anyway, are those that end in the middle of the night or very early in the morning.
Also you may have to cast a very wide net, checking all of Business and Industrial for instance to find the clueless seller who doesn't even know what he's selling.
Miscategorized items often yield great bargains.


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## Stonebriar (Jul 3, 2014)

Marco Bernardini said:


> Generally a dividing head has plate full of holes (it's not a disc brake!!!) to help you to divide a circle into a precise number of parts without to have to calculate the angle.
> See these three videos:
> https://www.youtube.com/watch?v=pIg8InzUu3U
> https://www.youtube.com/watch?v=MXV7eV_WNEI
> ...





So I have seen both with the plates which means they can both index. What else makes them different?


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## Senna (Jul 3, 2014)

Stonebriar said:


> So I have seen both with the plates which means they can both index. What else makes them different?



My understanding is that a dividing head and a super spacer are one and the same. Merely different nomenclature.


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## chuckorlando (Jul 3, 2014)

I could be wrong here... My understanding is a super spacer runs off plates with notches in it. It is faster to use a SS spacer as a 6 notch plate will do 1 of 6 every turn. An 8 notch does 1 of 8 etc etc. So no counting or anything. But is limited in the number of divisions on the plate. A dividing plate set covers bout any divsion you could want and on the rare instances it does not, you can use a hole intended for 2x as many divisions or 3x or what ever. So for example if you needed 12 holes a 24 hole set up would work by simply skipping every other hole.


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## COMachinist (Jul 4, 2014)

Argonavis said:


> Thank you all for your comments!
> 
> @COMachinist, thank you for the images!  How are the dividing plates used/mounted with your rotab?  I've never seen dividing plates used with a rotab.
> Hannes.


Hi
They have 4 flat head screws that mount them to the hub flange. Then the spring plunger bolts to the worm shaft. 
One other thing you should think about. The older DH weigh about 40-65 lbs and some of the real old ones can get up to 100 plus. I'm 65 years old and to lift them up on to my machines, well I would need some help, crane or over head chain hoist or two men and a boy. You need to keep in mind what it is your doing. For me this is just a hobby. I do not do production runs, or  job shop stuff. There is no need for a DH/Rotary table that has more cast iron in it than small bock Chevy. :roflmao:
CH


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## Argonavis (Jul 6, 2014)

COMachinist said:


> They have 4 flat head screws that mount them to the hub flange. Then the spring plunger bolts to the worm shaft.



I confess this comes as a revelation to me -- I didn't realize the degree to which an RT & DH had overlapping functionality. I really appreciate the fact that you mentioned this!

While I am clear on some of the distinctions between a DH and an RT fitted with index plates, I'm quite sure I don't understand all the nuances.  I'll take a stab at making a quick-and-dirty list below.  Corrections and clarifications would be very welcome.  

An RT appears to have the following features:


 Pros
 An RT is intended to be rotated during a milling process. 
 A higher ratio (often 90:1) will improve the accuracy and reduce the influence of sloppy index-hole location. 
 My sense is that RTs appear to gain mass rather quickly as the radius (table-to-CL) increases.  This would tend to increase rigidity, even while decreasing "portability". 
 Since the RT has both a tapered spindle and a table with T-slots, work-holding is very flexible. 
 
 Cons
 Since their form factor is defined by the diameter of the table, they can get quite wide/high. 
 Similarly, the larger tables can get quite heavy. 
 The higher ratio requires more cranking, thus makes operations slower. 
 Most RTs appear to be either horizontal or H/V, but cannot pivot throughout a range of angles like a universal or semi-universal DH. 
 RTs don't typically have provisions to be synchronized with the table motion. 
 Due to the geometry of the RT handle, especially with index plates, the handle often must extend off the edge of the mill table which places some limits on the positioning of the RT. 
 
DH features:


 Pros
 Lower ratio (often 40:1) decreases the number of turns, thus increasing speed of operations. 
 Tend to be lighter than RTs of roughly equal capacity. 
 Tend to be more compact in form. 
 Universal & semi-universal models can pivot through a fairly wide range (> 90 degrees), thus making a variety of angled cuts fairly easy. 
 Some DHs have input shafts which allow the DH to be synchronized with the mill table motion. 
 The entire DH, with handle, sits high enough on the mill table that positioning is not as much of an issue as with an RT. 
 
 Cons
 Is not typically intended to be in motion during the milling process. 
 Work-holding options are more limited by not having a integral table with T-slots. 
 When used in the "horizontal mode" (vertical spindle axis) the overall height of the DH plus the chuck or work-holding fixture can make it difficult to use effectively.  Rigidity can also suffer in this orientation. 
 The lower ratio, especially with some 4:1 DHs, can make accurate placement of index plate holes much more critical. 
 
If this synopsis is reasonably accurate, it seems as though the RT is a slightly more flexible device, generally, even while being somewhat more cumbersome in some ways.  Would that be a fair statement?

Hannes.


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## Andre (Jul 6, 2014)

Senna said:


> My understanding is that a dividing head and a super spacer are one and the same. Merely different nomenclature.



Super Spacer (Spin index, spindex)
http://server2.smithy.com/iadmin/sites/default/files/pictures/products/67-050-Spin-IndexerLR.jpg


Dividing head
http://www.use-enco.com/ProductImages/0023017-24.jpg

They are basically the same, but a dividing head offers more accuracy, flexibility, and the option to mount a chuck, unlike a spindex. You *can* mount a 5c arbor chuck on a spindex, but then your asking for tolerance stacking and flex in the device.


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## chuckorlando (Jul 6, 2014)

For the most part your correct. Although all DH do not have the same ratio. A RT can still mill at angle with a sine plate. And a 6in chuck can fit a 6in table. Sp LB for Lb I think the RT would weight less by capacity comparison. But as you mentioned, a 6in table would have much less mass behind it then a like size DH.


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