Turning a MT2 taper

Been really busy lately with all kinds of different projects. In thinking about the week ahead and what I need to get done I thought why do I need to turn a MT2 taper on this bullnose. So my current plan is to turn the current MT3 taper down to .700 which happens to be the max OD for a MT2 taper. Then put this into an ER32 collet in my ER32 to MT2 adapter. It may stick out to far to be supported by the ER32/MT2 adapter. Add a steady rest to the picture to help support the bullnose. I'll take a picture of the setup when I get to this project. I can then attack the MT2 taper later.

My most pressing project this week is to finish making an aluminum sheave to go on the boom of a friend's sailboat. Will need to make an arbor to do that. Another first time project for me.
 
Just for the record, I've cut very accurate matching external and internal tapers like this: Set the compound at the chosen taper angle, but keep the dial to the right of the cross slide. Then cut the external taper with the lathe in reverse and cutting on the back side of the part. Without changing the compound angle, now cut the internal taper running in the forward direction and cutting normally on the inside front of the bore. The tapers match basically perfectly.
 
…This bull nose live center is heavy. It weighs 12 lbs. No way am I going to use an adapter hanging off of the tailstock ram…

In order to use a 9” MT5 bull nose live center in my MT4 tailstock, I use a cheap import “MT4 to MT5” extension socket. The weight of this MT5 bull nose live center (70 lbs.) has not yet caused any issues. Having said that, I am mindful about never having the tailstock quill stickout any longer than it needs to be (a practice which applies in all other cases anyway).

Even with the [70 lbs. + half the weight of the extension socket] on there, I would feel entirely comfortable extending the tailstock quill all the way out if I needed to.

As far as turning a male Morse taper, the first time I did this I overshot it a tad on my first 2 tries. The third time was a charm. So make sure to **really** sneak up on it! I used the compound, and you have to really microadjust the angle on the compound in order to get the desired “thou per linear inch” taper just right.

Interesting note: the 2 failed attempts mentioned above still work fine in the factory Morse taper spindle. Although I was pleased that I didn’t need to scrap the work, I thought this was weird; I guess there is a larger allowable tolerance than one would expect.

I suggest that you spend a lot of time using a DI to see what your compound angle adjustment yields until you have it right where you need it to be.
 
Last edited:
Back
Top