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ptjw7uk
07-07-2009, 08:14 PM
Getting my cnc bits together slowly, I recently obtained a 80mm chuck for my rotating table (100mm dia).
I thought that the front mounting ones were a trifle on the expensive side so bought the rear mounting type. Machined a disk to fit the rear and as luck would have it it already had 3 holes near the circumference that will make fitting to T nuts (still to make them) and have now run into a bit of a problem.
The rotab has a 2 morse taper fitting in the centre BUT the chuck only has a 16mm hole through the middle which is smaller than 2mt, so I am now trying to find a simple way of possibly cutting a 2mt down so it fits in 16mm or ....
Open to ideas.

Peter

John S
07-07-2009, 08:21 PM
The rotab has a 2 morse taper fitting in the centre BUT the chuck only has a 16mm hole through the middle which is smaller than 2mt, so I am now trying to find a simple way of possibly cutting a 2mt down so it fits in 16mm or ....
Open to ideas.

Peter

MT2 is only 0.600" on the large end ?

.

ptjw7uk
07-07-2009, 08:35 PM
John,
I have just been to the shop and measured a 16mm 2mt drill and the large end of the mt is 18mm dia.

Peter

John S
07-07-2009, 10:10 PM
Sorry, brain fart it's 0.700", forgot to put the clocks forward.

.

BillTodd
07-07-2009, 10:13 PM
What are you trying to do with the 2MT ?

2MT expands to 16mm in about an inch from the small end. It'd be easy to grind a step at the big end down to 16mm (although if that's all you need what about a Jx chuck arbour?)

ptjw7uk
08-07-2009, 04:51 PM
Bill,
The 2mt is to align the centre of the chuck to the centre of the rotab, not sure if a jx chuck arbour would have enough height for the chuck to grip.
When I get some time in the shop I will trytruning down the outside of a 2mt sleeve and proceed from there.
I had thought of using a 1mt drill but I am not surewhat the spiral on the drill will do, perhaps a reamer will do mor flutes to grip on.
I could also have a go at taper turning a steel rod to fit 2mt.

Peter

BillTodd
08-07-2009, 09:34 PM
The 2mt is to align the centre of the chuck to the centre of the rotab
You'd normally do this with a dial gauge (mounted in the milling chuck) by tapping the rotab-chuck until the job is centred.

If you just want to quickly centre the chuck just drop a length of 1/2" or 16mm rod down the chuck until it centres in the taper then tighten the chuck (admittedly, turning a short 2MT onto the end of the bar would make a better job of it).

ptjw7uk
08-07-2009, 10:21 PM
I agree that I could use a clock to dial it all in. BUT I thought it should be simple(easy) to align it with a bar and then perversity kicked in so as I originally said 'nothing in life is simple'.
One of my likes about diy engineering is the seemingly simple ideas people have thought up to overcome difficult machining problems and I am often amazed at what has been accomplished on the 31/2 Myford lathe usually without a mill etc.

Peter