# What the heck is a "Dividing" rotatry table?



## injunear (Jan 2, 2014)

What the heck is a "Dividing" rotary table? I am the proud owner of a 4 inch "dividing" rotary table from India......What is the significance of the term 'dividing' on this rotary table?

Thanks
Bob T.


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## xalky (Jan 2, 2014)

If it came with indexing plates, it's a dividing rotary table.


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## atwatterkent (Jan 2, 2014)

It's a rotary table that has the dials replaced with dividing plates. Here is a photo of mine.


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## Bill Gruby (Jan 2, 2014)

A rotary table is capable of easily breaking down a 360 degree circle by even numbers. It can also have the rotary dial replaces at will with dividing plates. Then as a  dividing head it can split hairs when it comes to the break down. A dividing rotary table is the best of both worlds, it can be used as either. I have a 6 inch that does both.

 "Billy G"


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## injunear (Jan 3, 2014)

Thanks all. It did not come with plates but it is advertised on ebay, where I bought it, as a dividing table.

Bob T.


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## valleyboy101 (Jan 3, 2014)

*Re: What the heck is a &quot;Dividing&quot; rotatry table?*

Bob T.
You're lucky you got the tailstock as they are frequently missing.
Michael

- - - Updated - - -

Bob T.
You're lucky you got the tailstock as they are frequently missing.
Michael


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## Bill Gruby (Jan 3, 2014)

You can get the plates from Grizzly Industrial. Can you post a picture? Sounds like you have a Rotary Table only. Someone didn't know how to advertise it.

 "Billy G"


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## sgriggs (Jan 3, 2014)

Or you can make your own plate.  This is the drilling of the hole pattern.  It was later cut out and turned to size.




Sent from my Nexus 7 using Tapatalk 4


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## Bill Gruby (Jan 3, 2014)

On a rotary table the ratio is usually 90:1. On the dividing head it is usually 40:1.

 "Billy G"


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## Rbeckett (Jan 3, 2014)

The three and 4 inch rotaries are usually 72 or 40 to one ratios,.  A quick look at the manual will tell you exactly which one that you have.  In the dividing and rotary world, more is always better than less because it allows for more accurate placement of a hole or feature.  Hope this helps...

Bob


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## george wilson (Jan 4, 2014)

I made a brass dividing set for my 6" rotary table years ago. I found it quite easy to step off the numbers of holes with dividers. After a few adjustments,each row of holes was accurately stepped off. Then,carefully ***** punched. I even used a pump drill to start each hole by hand. The old fashioned pump drill can very accurately drill holes. It is slow,and you can tip it some to bring holes back on center. Later,I drilled and beveled the holes deeper with a small center drill in the drill press.

At 90 to 1,any tiny discrepancy would be vastly reduced on your project,though I could not see any lack of accuracy on my dividing plate.

Early Dutch clock makers divided gears entirely by hand with a trick: They made a much larger circle with the gear fixed to its center. Then,they'd step off the spaces with dividers. When properly stepped,they took the dividers and swung the stepped off spaces down to scribe them on the O.D. of the gear. This use of a much larger plate enabled them to further reduce inaccuracies in the smaller gear.

Later on,dividing engines came along. But,they were expensive and many a clock was still made the old way by hand dividing.


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## injunear (Jan 4, 2014)

Bill Gruby said:


> You can get the plates from Grizzly Industrial. Can you post a picture? Sounds like you have a Rotary Table only. Someone didn't know how to advertise it.
> 
> "Billy G"



I can't seem to copy the photo from ebay but here's the link to the same item I bought. It comes from India and frankly, I was shocked at how fast I got it. It arrived in a little over a week.....

http://www.ebay.com/itm/NEW-DIVIDIN...d=100012&prg=1014&rk=3&rkt=3&sd=231108745498&


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## injunear (Jan 4, 2014)

Rbeckett said:


> The three and 4 inch rotaries are usually 72 or 40 to one ratios,.  A quick look at the manual will tell you exactly which one that you have.  In the dividing and rotary world, more is always better than less because it allows for more accurate placement of a hole or feature.  Hope this helps...
> 
> Bob


It does help, thanks. Mine is 40, or close to it. I think it says 36.....


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## coyotejake (Jan 5, 2014)

Looking at the e-bay pic, you do not have a 'dividing' table, but a rotary table.  You will not have any use for the plates we use on our 'dividing' heads.  Fortunately, you will basically be able to do the same thing that we do with our 'dividing' heads, just not to the level of exactness that we can.  Your rotary table uses 360 degrees of markings and a pointer to reference your 'divisions'.  To make it easy, if you want to mill a square end on a shaft, you'll divide those 360 degrees of markings by four (sides of a square) to get 90 degrees.  So, turn your table to read 0 degrees, LOCK EVERYTHING DOWN, and make a cut. Loosen the rotation, turn your table to read 90 degrees, LOCK IT DOWN, and make another cut.  Rotate 90 degrees again, to read 180 degrees, make a cut.  Rotate 90 degrees again, to read 270 degrees, make a cut.  It helps to do the math beforehand and write it down so your sure where your rotating to for each cut.  As another example, a (six sided) hex is 360 (degrees) divided by 6 (sides) equals 60 (degrees per 'division').  SO, make cuts at 0 degrees, 60 degrees, 120 degrees, 180 degrees, 240 degrees, and 300 degrees.  Hope this helps.
  One more thing, though.  The set-up you purchased on e-bay MAY be a bit on the flimsy side, so be careful to lock things down tight, and take light cuts.


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## Bill Gruby (Jan 5, 2014)

The post before me is correct. That is a rotary table with a tilt option only. A set of plates will not work on that table.

 "Billy G"


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## injunear (Jan 5, 2014)

Ok, thanks guys. I really don't have a need for a dividing table at this time. This table will likely do for my model airplane "stuff" for now. I'm not going to be making anything that requires any level of repetitive accuracy.

Funny thing, they continue to advertise this thing a dividing table.....

Bob T.


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## melsdad (Jan 7, 2014)

injunear said:


> Funny thing, they continue to advertise this thing a dividing table.....
> 
> Bob T.



Some Ebay sellers title items like that on purpose to get more hits when people do a search for a certain thing. Somethings you need to be careful and investigate the item before committing to buy.


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