MT3 tailstock issue

[Rellortnoc]

Do you mean like how to hold it so you can drill & tap the center or whatever? If yes, here's how I hold them. They make straight MT sleeves but are expensive or can cut down a MT extension. I just bought the cheapest thing I could find that had a Morse Taper with straight OD which was a R8 to MT3 adapter that was like $10 shipped. Cut off the portion I needed. It was actually ground concentrically on the OD too. Of course you could just make one also.

I actually just did this one a few weeks ago.

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Thanx! This is the solution I was looking for which was how to chuck up the taper.

 

[Downunder Bob]

I have a Grizzly G0602 and am new to machining. Recently purchased a Jacobs 5/8 chuck with an MT3. The problem is that the taper shaft is so long that I have to run out my tailstock half way just to seat it. That only leaves me about an inch or less to center bore. Then I have to move the tailstock closer to cut deeper. Is there precedent for cutting some of the MT3 shaft off? Seems like a logical option, but as I said, I’m new to machining and don’t want to make a blunder.

Years ago I acquired an MT2-3 sleeve. it was in the scrap bin, someone had thrown it out. After retrieving it fro the bin and cleaning it up I realised it was bit short, the tang had been cut off, so it would not eject when wound back. so it was a pain to use. I drilled a hole in the small end tapped it maybe 5/16, don't remember, fitted a SHCS that was just long enough for it to be ejected. problem solved

 

[Rellortnoc]

UPDATE: Took an inch off the tang end of the MT3 taper and it was perfect. I can seat it and run all the way from zero to the limit of travel. Just a little over 2 inches. The tail stock will recede a full 1/4 inch below the zero mark which allows for ejecting the taper.
Thanx for all the advice. (However, I did look up a replacement in case I screwed it up, LOL)

 

[brino]

New to all his and don’t know all the terminology yet. I’ve seen some tapers that were actually bored and tapped instead of a tang. You could insert a bolt to adjust your overall length If needed.

Those tapped holes in the end are meant for a draw-bar to pull/hold the taper into a hollow spindle on mill or lathe.
You can buy many tools either with a tang or with the tapped hole for a draw-bar.
For your next tool you may want the "draw-bar" type.
-brino

 

[Tozguy]

There is at least one exception to having a 3/8 NC drawbar thread in the small end of an MT3 taper.
My live center on an MT3 taper has a 12mm x 1.75 thread and what seems to be a simple threaded plug. It is not clear why the body of the live center is bored through as the OEM spindle only extends a third of the way in. However the through bore sure made it handy to press/pound out the spindle when I decided to make a longer spindle and add bushings.