MT 5, 6 or something else

[killswitch505]

I’m trying to get a center for my lathe. it’s bigger than MT5 and not MT6. Any help would be appreciated!

 

[Braeden P]

Do you have the manual or have a pdf version that should say what taper it is

 

[erikmannie]

What model of lathe is it? I was in your position & I made 4 dead centers which was not a difficult project. I had a tapered reducing sleeve on hand to use as a model, though.

You’ll probably end up making your own. Like I said, not difficult. The resulting angle will be somewhere between 1 1/4 to just over 1 1/2°.

For best results, start with 10” long, 3” OD 4140 prehard. 1045 is okay, too.

There is no penalty for cutting the taper angle too steep & then gradually reducing the angle until it fits properly. Once you have your compound set to just the right angle, knock out 2 or 3 dead centers of varying lengths.

 

[killswitch505]

Do you have the manual or have a pdf version that should say what taper it is

I ordered an operating manual there isn’t very much to it and they don’t specify the taper

 

[darkzero]

Maybe it's that odd MT5.5 again.

 

[killswitch505]

Erik, looks like that’s what I’ll have to do. my head stock is a bit out of alignment I was hoping to pop a center in and align it and align the tail stock because I’m fairly certain that out as well. I’m not sure how to move forward with those operations now

 

[killswitch505]

Maybe it's that odd MT5.5 again.

Oh gosh is that a thing

 

[darkzero]

Oh gosh is that a thing

Yeah, some Taiwan lathes with D1-5 (big bore) & MT-6 lathes have em. MT5.5 is not a Morse Taper standard but it exists. Not sure if any Grizzly lathes have em (that would be the easiest to order a sleeve) but the PM1440GT uses it. Maybe you can buy the sleeve (MT5.5 to MT3) from QMT/PM or make one.... if that's what it is.

 

[darkzero]

Here's a thread from last year about another member having the same issue. He ended up getting one made, not sure if he ever confirmed if his was actually MT5.5 but like you the size was in between MT5 & MT6.

Confused with spindle specs

My Yang 14x22 lathe spindle specs are in the attached picture. What is the "Center" in Taper of Center - Morse Taper #3? The Spindle bore is 1.77", and that is a lot bigger than a MT3. There is also a Taper of Spindle Bore 1/30. Is the the inside taper of the spindle nose? The tail stock taper...

www.hobby-machinist.com

 

[erikmannie]

If you got to the point (e.g. by making one) where you have a dead center in the spindle nose, you would re-cut the 60° angle at the tip of the dead center while it is in the spindle nose, and then the tip would be perfectly centered. Not the worst situation to be in.