# Aligning A Cheap Chinese Dividing Head/rotary Table Combination



## CarlosA (May 2, 2016)

So I have an x2 mini mill, and a rotary table package - specifically this one: http://littlemachineshop.com/products/product_view.php?ProductID=1931&category=

There are some little keys on the bottom side of both the tail stock and the table ... they are roughly 3/8" wide - the opening in the x2 slots is roughly .46" wide. How do I set this up in a way that it is repeatable?

On another mill that only had two slots I had a real nightmare of setup trying to get it aligned and clamped down with some funky home made clamps. The x2 is new ... so having the indexing setup work with it easily is important to me.

Any ideas or experiences?

_
Edit to add a little more info as I know this will confuse some:

I am looking for quick ways to set this up in its vertical setup, with the tail stock - so that if you were to sweep the table, with a test indicator on a rod between centers, it would be perfectly straight. Not looking for info on finding the center of the table (not yet anyway)._


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## stupoty (May 2, 2016)

As it's got a flat bottom it would seem easiest to align the rotary table with a square when in verticle mode or a dial indicator if you were looking for higher accuracy.

I guess the easiest way to align the tail stock depends on how your holding the work in vertical mode.

Stuart


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## CarlosA (May 2, 2016)

stupoty said:


> As it's got a flat bottom it would seem easiest to align the rotary table with a square when in verticle mode or a dial indicator if you were looking for higher accuracy.
> 
> I guess the easiest way to align the tail stock depends on how your holding the work in vertical mode.
> 
> Stuart



Yeah it does have a flat bottom but with two little keys sticking out. I think the appropriate way must be to just push it against one side of the t-slot with these keys, then it should be dead on - I haven't checked yet, mostly just looking for some tips or tricks.

My intention is to hold the work between centers with a lathe dog. My current biggest use for this will be making a lot of gears for a spur gear differential project.


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## stupoty (May 2, 2016)

CarlosA said:


> Yeah it does have a flat bottom but with two little keys sticking out. I think the appropriate way must be to just push it against one side of the t-slot with these keys, then it should be dead on - I haven't checked yet, mostly just looking for some tips or tricks.
> 
> My intention is to hold the work between centers with a lathe dog. My current biggest use for this will be making a lot of gears for a spur gear differential project.



Might depend on how square the tee slots are, slightly less critical if your between centres as you can align the tail stock with the mandril that will hold the gear being cut and the centers will alow a small amount of out of square unlike a chuck which will hold it at the angle the rotart table (dividing head) is set at.

Stuart


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## CarlosA (May 2, 2016)

stupoty said:


> Might depend on how square the tee slots are, slightly less critical if your between centres as you can align the tail stock with the mandril that will hold the gear being cut and the centers will alow a small amount of out of square unlike a chuck which will hold it at the angle the rotart table (dividing head) is set at.
> 
> Stuart


Good point on that ... roughly setting this up then dialing in with the tailstock is the ticket. I could never use the tailstock before, so held my arbors in a mt2 collet and always ended up with weird issues on the final gears even when everything seemed perfect on the dial indicator.


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## Nammar (May 2, 2016)

Dear CarlosA,

The way that I was taught is that you have to make up a test bar. Take a piece of 12" by 1" roundbar, drill two centre holes in it's ends, on your lathe and take a parallel cut between centres. Once you have corrected the error of your lathe and both ends of the test bar measure the same diameter, you can then use the test bar in your milling machine as well, to set the tailstock of the dividing head as well as the alignment of the bar to the table axis.

I hope that this helps you. Geoffrey.


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## David VanNorman (May 2, 2016)

If the rt has keys just make a set of keys that fit your table slots . You would half to make keys for  the RT and the tail stock.


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## Bob Korves (May 2, 2016)

Make a step key to fit the slot.  Also make step keys for the horizontal orientation.  Make them accurate and tight fitting and you don't have to mess around setting it up each time.

Edit:  David beat me to it.  Need to learn to think and type faster...  8^)

Second edit: Use the same method for mounting the vise. Saves lots of fooling around setting it up with jaws parallel to the table.

Third edit: Welcome to the forum!


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## chips&more (May 2, 2016)

I would mount a chuck on the rotary table and do away with the tailstock all together. I also have a tailstock, but can’t remember the last time I used it? I just mount everything in the chuck or a collet. And as said, if you want the keys to fit, then you will need to make new ones. There are no tricks that I know of to get around sloppy fitting keys. Other than shoving it to one side…Dave.


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## Whyemier (May 2, 2016)

David VanNorman said:


> If the rt has keys just make a set of keys that fit your table slots . You would half to make keys for  the RT and the tail stock.



Yes, I'd do that unless you don't want to modify the rotary table.  Then you might consider machining a fixture plate with a 3/8" slot to accommodate it and do a key in the bottom of the fixture plate.

I did something similar recently, cutting a tee slot in an existing small slotted 'table' I had.












IMGP0500



__ Whyemier
__ Apr 11, 2016



						T-Slot


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## CarlosA (May 2, 2016)

Bob Korves said:


> Make a step key to fit the slot.  Also make step keys for the horizontal orientation.  Make them accurate and tight fitting and you don't have to mess around setting it up each time.
> 
> Edit:  David beat me to it.  Need to learn to think and type faster...  8^)
> 
> ...




Yeah I think you are right. I think I also doubt my ability to get them right, so that everything is right on when they are mounted. Will give it a shot of course.

And thanks.


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## Tony Wells (May 2, 2016)

Don't assume the table slots are all that accurate. Stick an indicator on the side and run the table. You might be pleasantly surprised, or dismayed. If you want or need to work to 0.001-0.002 accuracy, you'll indicate your part or fixture anyway. The keys are for production work, typically less demanding.


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## CarlosA (May 2, 2016)

Tony Wells said:


> Don't assume the table slots are all that accurate. Stick an indicator on the side and run the table. You might be pleasantly surprised, or dismayed. If you want or need to work to 0.001-0.002 accuracy, you'll indicate your part or fixture anyway. The keys are for production work, typically less demanding.



Yet another good point, lol. I just really hated dialing in the dividing head every time I had to set it up, since i`m making many gears. I will try & see how accurate the slots are, I didnt even consider that they may be rough cut.


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## Tony Wells (May 3, 2016)

It is possible to skim one side of the slot, and then push your keys against it. You won't be able to cut the entire length, but that's something you may can live with. The you could make some good step keys to fit. I still would bet you'd want to indicate your fixturing in, but it would get you pretty close.


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## Bob Korves (May 3, 2016)

CarlosA said:


> Yeah I think you are right. I think I also doubt my ability to get them right, so that everything is right on when they are mounted. Will give it a shot of course.
> 
> And thanks.


Keys are just little chunks of steel.  Cut them until they fit nicely.  If by mistake you cut too deep, put them aside and make more, until they are correct.  Then round all the corners and edges so they do not dig into the table and gouge the table slots.  Use socket head cap screws, counter bore so they sit below the surfaces, so you do not scratch your table.  I make them just loose enough to fall into the table slots easily, which leaves enough play to dial the table and tail stock in if the work requires it, otherwise, bolt it down and git-er-done.


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## CarlosA (May 3, 2016)

So I swept the table with a .0005" test indicator and it does stay between 0 and .0005" the whole way ... it moves a bit from catching on rough metal, etc but as you lock the table in each spot it drops right back to that tolerance. I was kind of surprised really.



Bob Korves said:


> Keys are just little chunks of steel.  Cut them until they fit nicely.  If by mistake you cut too deep, put them aside and make more, until they are correct.  Then round all the corners and edges so they do not dig into the table and gouge the table slots.  Use socket head cap screws, counter bore so they sit below the surfaces, so you do not scratch your table.  I make them just loose enough to fall into the table slots easily, which leaves enough play to dial the table and tail stock in if the work requires it, otherwise, bolt it down and git-er-done.



I will do this, I was thinking it can be the shape of a T but its not necessary - can do the shape of an L so that one side can be used for getting everything dialed in in the vise. Worst case i`ll lap it in the rest of the way, spend some time on it once so it drops in every time.


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## dlane (May 3, 2016)

May try tightening table gibs , might help with table movement when locking it
If it has any


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