# Method for Aligning the Tailstock with Headstock



## barrydc1 (Mar 12, 2013)

The following is a communication that Richard King wrote to a person who was indicating the tails stock (TS) quill from the chuck:

"I would not indicate the center hole of the tailstock spindle with mag base mounted on the chuck as the indicator will always droop or sag when it is turned over.  There is a very simple method to prove this."



The procedure follows. 
1)     Mount the mag base on a flat piece of bar stock say 1" x 3" x 10" 
2)      extend the indicator out as far as you can go


3)       Put 1/2 turn of pressure on indicator and zero it.


4)       Flip the bar stock upside down and check the error.  



With this factor known mount the same mag base on your chuck and check your spindle and subtract the error you had from the bar. (be sure you have the indicator rod set at same length,)  You will get less deflecting error the closer you can mount the indicator to the TS your checking. This is not a recommended method!

The better method:
1)      Measure the OD of your tail stock (TS) quill.



2)      Chuck up a round bar stock in your chuck that is bigger diameter then TS quill.


3)      Turn it down to the same size.


4)      Move TS up as close to the Headstock (HS) test bar with TS quill out 3/4 of the quill travel and lock quill and TS down to bed.
5) Mount a mag base to cross slide or compound





6)      Check the side of test bar and quill to be sure they are aligned side to side.


7)      If they are off adjust TS sideways to match your HS test bar. (No picture here, sorry, mine didn't need adjusting but this is done by tightening one of the, usually, allen socket head screws on the sides of the tailstock and loosening the other while watching the DTI, 1/2 the distance to zero it and re-checking until the headstock bar measurement is the same as the tailstock quill measurement).
8)      Do a top dead center test of HS test bar


9)      Move saddle down to TS, not touching mag base and indicator 
10)   Do a top dead center test of the quill to check if the centerline or TS is same height as HS centerline.



11)   Then move the saddle further toward the tailstock and check TS quill to see if it is parallel to centerline.



(don't look too carefully at the dial numbers of this first picture as I used the same pictures for the purpose of showing technique only and one was not zeroed when it was taken).
12)   The majority of the time the TS is pointing down and low because the dirt gets under the front.

I wll also be doing the following, which Richard included in his instructions, but I will add it to this post when I have done it myself and taken pictures:
13)   You may also want to check the ID hole of the TS to be sure it is not burred with the taper shank of TS chuck center or drill bit.  Check this with new drill with ground taper.
14)   Prussian blue the drill and rub it inside the hole and look in there with a flashlight.
15)    If you find the TS low and pointing down post and Rich will tell you how to correct this. Or call Rich if you want more info. 651 338 8141.

More pictures to come

Barry


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## Richard King (Mar 12, 2013)

That is exactly what I wanted to show the group.  Hopefully Tony will archive this for the generations to come.   Thank You Barry.

For those who have not seen the 2 collar headstock alignment test Barry did click on the following link and go to post 16.

http://www.hobby-machinist.com/showthread.php/12839-Enco-13x40-Spindle-bent-or-headstock-mis-aligned

Everyone please tell your friends in all the forums about these tests as they will save everyone lots of headaches.

Rich


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## tarmo120 (Mar 12, 2013)

This method is nice. But time consuming.

I'd like to ask Richard if the method I use has some drawback compared to the above.

I put the indicator without the magbase in the chuck. Then put the indicator at the beginning of the tailstock quill(outer diameter).
And then rotate the chuck, checking the offset of the tailstock quill.

I once saw it on youtube, and for me it is fast and I don't see any poblems with it.
Maybe it was shown by tubalcain. I'm not sure.


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## Richard King (Mar 12, 2013)

tarmo120 said:


> This method is nice. But time consuming.
> 
> I'd like to ask Richard if the method I use has some drawback compared to the above.
> 
> ...




It will work to get you close, but Indicators are not designed to be flipped over unless you order a special type or do the flip test.  Take your indicator and make a jib and attach the indicator to the jig and the distance you you have on your machine and pre test it.  I use this method when I am doing te fial tests on a machine I just rebuilt or am setting it up for a new customer.  This method also identifies error as to how the tail-stock is pointing .  99% of the time the TS is pointing down (top test) because of tool pressure and dirt and backwards because of tool pressure (side test)


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## rowbare (Mar 13, 2013)

Another method I saw on You Tube some time ago is to chuck a piece of stock leaving about 1 1/2 inches sticking out. Take a truing cut and center drill the end. Part off about 1/2 an inch. With the motor off, put a center in the tail stock. Take the piece you just parted off, put the center in the center drilled hole and hold it snugly against what is left in the chuck. Adjust the tailstock till you can't feel a ridge where the two pieces meet. 

bob


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## barrydc1 (Mar 14, 2013)

I promise I haven't forgotten, I've just had a lot of business stuff going on.  I even took pictures of the blueing and attempt at insertion of a center into my tailstock taper, but it is very difficult to see on photographs what the inside of the tailstock quill taper looks like after bluing.  I am pretty disappointed in the lack of contact of the center on the quill taper, but the actual run out I haven't measured yet.  I will post the pictures when I get a minute.,I need to get some advice as to how to measure how straight and true the tailstock taper is in relation to the rest of quill which I now know to be parallel to the bed and path of the carriage.  What are you thoughts on this Rich and others?

Barry


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## Richard King (Mar 14, 2013)

barrydc1 said:


> I promise I haven't forgotten, I've just had a lot of business stuff going on.  I even took pictures of the blueing and attempt at insertion of a center into my tailstock taper, but it is very difficult to see on photographs what the inside of the tailstock quill taper looks like after bluing.  I am pretty disappointed in the lack of contact of the center on the quill taper, but the actual run out I haven't measured yet.  I will post the pictures when I get a minute.,I need to get some advice as to how to measure how straight and true the tailstock taper is in relation to the rest of quill which I now know to be parallel to the bed and path of the carriage.  What are you thoughts on this Rich and others?
> 
> Barry



That's perfect, exactly like I wanted to show.  I just want to say these tests  are methods that are proven and used by professional machine tool rebuilders and not a guess or an attempt to discover a way of doing it by a hobbyist.  I hope Barry will post it on You-Tube.    I can make a copy of page 32 out of the "Testing Machine Tools" A book written by  DR. George Schlesinger.  His book is the standard that many machine builders and the ASME have used for years as a base to write their modern tests and machine tool spec's and are based upon.  The Dr describes a method is also described as a Double Mandrel Test.  where the uses 2 precision mandrels in a test practically identical to this method.  This and the 2 collar test Barry did was for you to align your machines the way I would do it.   Use it you want to.. Here is the info.

No need to include the TS center test unless you want to Barry.

Thanks Barry

Rich


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