Making Mt3 Chuck Holder

[taycat]

having learnt this week how to do a taper i would like to make a chuck holder.
need one end mt3 and other to be threaded.
found site that gives dia of each end of mt3 but not angle.
anyone tell me angle pls?
also do they need to be hardened?
have got about 10 chucks and would rather make bits myself.
thanks

 

[CluelessNewB]

This link has what I think you want. (Thanks to Little Machine Shop)

http://littlemachineshop.com/reference/tapers.php

 

[taycat]

thanks for that.
if i have worked it out right that makes it 2 degrees.
going to have go next week.

 

[thanvg]

hi there taycat,

speaking from (bitter, but not on the taper turning part) experience on a attempted MT3 collet, I would suggest not ro rely on angle settings.
Better, mount a good MT3 taper on the lathe, put a DTI on the toolpost and dead on center height, and adjust the top-slide's angle so that the DTI's needle stays fixed for the whole length of the top slide.

I think this is the most accurate way, be it top-slide or taper-attachment that you are using to turn a cone.

(of course, a good female MT3 cone and some engineer's blue would also be helpfull for the final touches)

 

[taycat]

did it got bit of 1" bar from scrap bin.
was a support post for hydraulic cylinder on one of machines at work before we re-furbed them.
top of pic is what i started with bottom is finished thing.
the 2 flats are for spanner to hold it when changing cylinders in its previous life.
only another 7 to do to fit all my chucks.

 

[taycat]

not perfect by any means but for first ever go am well happy.

 

[RJSakowski]

did it got bit of 1" bar from scrap bin.
was a support post for hydraulic cylinder on one of machines at work before we re-furbed them.
top of pic is what i started with bottom is finished thing.
the 2 flats are for spanner to hold it when changing cylinders in its previous life.
only another 7 to do to fit all my chucks.

View attachment 98828

thanks for that.
if i have worked it out right that makes it 2 degrees.
going to have go next week.

Taycat, A MT3 taper has an angle of 1 degree, 26 minutes, and 16 seconds or 1.4377 degrees per side. The taper is 1:19.902 which is .0502 inches/inch. If I recall properly, the taper definition is in inches/inch rather than degrees.
If you are planning to use the MT3 taper to mount parts in the headstock you should use some sort of retainer to hold it in place. Either a collar attached to the spindle or a drawbar. A loose chuck bouncing around your shop could do serious damage.

 

[w9jbc]

I have made chuck arbors out of old MT2 tools before they've worked out ok

 

[BillWood]

Is the reason for doing this to prevent a stuck chuck on the threaded lathe mandrel ?

Intuitively, it appears to me that on my lathe (SB 9' clone) the threaded part is far more substantial than a taper inserted into the headstock might be - but I am a newb. at this sport.

Bill

 

[janvanruth]

before making others check the first one out
if you dont have dikem or the likes:
take a whiteboard marker and draw lines lengthwise on the taper
insert into tailstock, twist and take out of tailstock
the lines, or rather where the lines were, will tell you the contact it makes

i fear you will find the area of contact is less than optimal....

you could releave the middle part of the taper, leaving about an inch at both ends to size
it will make getting the taper to fit easier and wont make the holding capacity much less