Problem with mandrel getting loose

Signed-In Members Don't See This Ad

Eddie123

Member
Joined
May 14, 2010
Messages
57
Location
Hordaland, Norway
Hello fellow penturners.

I have got a small, but irritating problem.

When I put my blank on the mandrel, I always tighten up the back before i
tighten the nut on the mandrel.

When I start to turn, the entire mandrel rod unturn itself from the mt2 shaft, and then the nut come sloose, of course after the blank has become so loose that it stops on the chissel.

Anyone experienced this, and have a fix for it ?

Thanks

Vegard
 
Signed-In Members Don't See This Ad

its_virgil

Member
Joined
Jan 1, 2004
Messages
8,124
Location
Wichita Falls, TX, USA.
Someone help Vegard. I don't use the mandrel that screws into the MT2 arbor. I have adjustable mandrels so I've not experienced what he is asking. I would suspect a drop or two of thread locker or CA would stop the problem of the mandrel unscrewing from the MT2 arbor and that would probably solve the brass nut issue. Help him out.
Do a good turn daily!
Don

Hello fellow penturners.

I have got a small, but irritating problem.

When I put my blank on the mandrel, I always tighten up the back before i
tighten the nut on the mandrel.

When I start to turn, the entire mandrel rod unturn itself from the mt2 shaft, and then the nut come sloose, of course after the blank has become so loose that it stops on the chissel.

Anyone experienced this, and have a fix for it ?

Thanks

Vegard
 

zig613

Member
Joined
Jan 8, 2008
Messages
647
Location
Canada
Vegard...

Make sure your 60 degree centre in the tail stock is snug tight to the end of the mandrel shaft (but not too tight to bend the shaft). Then make sure the tail stock is locked. If it locked the shaft shouldn't unscrew its self from the MT arbor.

Wade
 

nava1uni

Member
Joined
Mar 30, 2008
Messages
4,936
Location
San Francisco, CA, USA.
I would clean out the MT shaft with alcohol and then blow it dry. Once dry I would use lock tight and allow it to dry. Once dry tighten your brass screw and then snug up, but don't over tighten the tail stock. That should solve the problem.
 
Joined
Sep 24, 2006
Messages
8,206
Location
Tellico Plains, Tennessee, USA.
I turn between centers now so can't be of much help, plus when I do use a mandrel, I use the one from PSI that screws over the headstock spindle, so don't have much problem with it coming loose... sometimes I get a little problem getting it loose.
 

Eddie123

Member
Joined
May 14, 2010
Messages
57
Location
Hordaland, Norway
I can't imagine why the mandrel shaft would loosen from the taper.. the
way the motor is turning and the tool is applying force in the opposite
direction, this should tighten the mandrel shaft!

This might sound dumb, but which way are you mounting the mandrel?


Hi.

Not too dumb a question ! :)

I do put it on the right way around, with the taper bit on the head stock.
I have noticed that the tail stock moves back a little bit, maybe I have to look into that, but i i really attach it hard, so it looks like it is a strong force pushing it back.

The nut coming loose from the mandrel, is just like as if I rapidly brake down the speed of the lathe, then the nut will come loose, but that is not the case this time.

Maybe I must take the advice, and use a bit of locktite.

Vegard
 
Top Bottom