Morse cone taper problem

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Shan

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Hello Folks and happy New year! Was hoping someone can advise me on an issue with a Morse cone taper that I unfortunately stuffed-up.
It is a #3 & is the live centre on my lathe for turning wood. I was using it recently and the thing started to wobble and was difficult to remove. Had some score marks on taper once I eventually got it out. My fault as the wood it was holding I hadn't made it flat where it centred and then came loose!
The problem is the taper (male) as had used other live centre's and are fine so no need to ream the female part. Should I clamp the Morse cone taper in the lathe chuck and sand it with fine wet and dry or simply try and polish the taper? Regards Shan
 
Confine yourself strictly to the damaged areas and ensure they are below the surrounding surface with nice smooth transition to that surface. No sharp bits.

On no account do anything to the entire bearing surface.

Innumerable Morse taper Jacobs chuck arbors are relieved on the centre portion (e.g. see Arbor_Jacobschuck,Power Tool Chuck,Industrial Chuck, MEDICAL CHUCK,Machine Tool Accessories) so there is no need for full bearing contact over the entire taper length.

Unless the damage is severe, you will never remove an area of metal equivalent to that shown on the factory Jacobs items.
 
Confine yourself strictly to the damaged areas and ensure they are below the surrounding surface with nice smooth transition to that surface. No sharp bits.

On no account do anything to the entire bearing surface.

Innumerable Morse taper Jacobs chuck arbors are relieved on the centre portion (e.g. see Arbor_Jacobschuck,Power Tool Chuck,Industrial Chuck, MEDICAL CHUCK,Machine Tool Accessories) so there is no need for full bearing contact over the entire taper length.

Unless the damage is severe, you will never remove an area of metal equivalent to that shown on the factory Jacobs items.
Chai latte, many thanks for your response. Was helpful seeing the Jacobs taper as didn't realise that it was hollowed out half way down the taper.

The damage isn't major and only a very slight play when it's engaged in the tailstock so hopefully I can sort it out. I'll just concentrate on the high areas.

Many thanks for the advice. 🖒🖒🖒
 
Chai latte, many thanks for your response. Was helpful seeing the Jacobs taper as didn't realise that it was hollowed out half way down the taper.
This is a typical mis-understanding which could lead to incorrect assumptions.

A Jacobs Taper is NOT a Morse Taper - and a Morse Taper shank is not a Morse Cone!!

A Jacobs CHUCK is often fitted with a Morse Taper Shank which has a Jacobs Taper. Here is an anotated image to avoid confusion.
Morse - Jacobs A.png

This particular image shows the Morse Taper shank with a centre 'relief' but not all shanks have that.
The damage isn't major and only a very slight play when it's engaged in the tailstock so hopefully I can sort it out. I'll just concentrate on the high areas.
If there is ANY play then the shank is not properly seated in the socket and the likelyhood is that the 'damage' to the shank has not been fully removed.
 
If there is ANY play then the shank is not properly seated in the socket and the likelyhood is that the 'damage' to the shank has not been fully removed.
J-G, I finally managed to put the live centre in the chuck and sanded the taper with some fine 320 grit wet and dry. Knocked off any high spots and it feels much better in use. No play whatsoever. Was thinking I may need to polish the shank but don't think I will bother.
Thanks for the advice and pointing out the difference between a Jacob's and Morse cone taper. Good to know for future reference and I'll be more careful about using the live centre now. Cheers Shan
 
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