# T Slot Spacing



## BROCKWOOD (Jun 11, 2017)

Is there a Standard for the spacing of T Slots on a mill table?  My Van Norman has a center to center of 2.500".  The tail stock I'm looking at has 4 mount holes with a spacing of 2.750".  All input welcome!


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## 4GSR (Jun 11, 2017)

I have never seen a standard for tee slot spacing on any machine table.  Now there may be a DIN/ISO standard that may apply to newer modern machinery, but I doubt it.   It's aggravating, isn't it.  I've ran into the same problem many times over the years, too.  Just have to improvise and make it work.  Same problem with all 8" super spacers out there, too!


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## Bob Korves (Jun 11, 2017)

Another approach is to buy a tail stock that is not as tall as your dividing head or whatever, and then make an adapter plate to bring it up to the correct height.  That is also a recipe for getting one tailstock to fit multiple tooling with different heights.

Edit: Of course, the adapter can also be fitted to the table slot spacing as well, my main point.


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## darkzero (Jun 11, 2017)

In regards to what Ken mentioned about Super Spacers & what Bob mentioned about  adapter/riser plates. That's exactly how I had to use my 6.5" Super Spacer on my mill/drill. The slots on the SS didn't line up with my slots so I had to use it by mounting it on a piece of tooling plate. Luckily my 8" rotary table lines up with my table perfectly. I had a 6" RT before & I would've had to use a riser plate with it also.








Eventually it bugged the hell out of me cause I use my SS in both the vertical & horizontal positions quite often. So I fixed that by machining the slots. I don't own any angle plates so I had to get creative with stuff that I had to hold the SS but I got it done.

http://www.hobby-machinist.com/threads/super-spacer-adjustment.25661/

The slots before:






And the slots after:






I have 2 tailstocks, 6" & 8". The style I have have the mounting slots inline with the center so it's mounts to the table with 1 slot. Downside to these is you may loose capacity along the X axis if your table is not very long. But I seem to manage fine with what I do. Below is the 8" tailstock.


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## BROCKWOOD (Jun 12, 2017)

Thanks, darkzero. Looking good. I made a low offer on the tailstocks I have my eye on. Still a bit more than plan B. We'll see. I figure I can Tell bolt 1 side & clamp the other.


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