Thread: Lathe Chucks - Appropriate Size

I often run my 8" chuck whick is the same thickness as yours with up to 8kgs on it.
Between centres I have spun up to 25kgs.

I was just about to say Pipeclay would be the person to ask, but he beat me to it.

Dave

Assuming it is balanced and doesn't have a huge amount of overhang. I would have thought the load on the bearing from cutting would far outweight the weight of the chuck and workpiece. From memory the bearings in my lathe are the same size as truck wheel bearings, so a couple of tons shouldnt be a problem.
Of course I could be wrong
Stuart

Originally Posted by pipeclay

I often run my 8" chuck whick is the same thickness as yours with up to 8kgs on it.
Between centres I have spun up to 25kgs.

What lathe is the 8 inch chuck mounted on Peter?
I should have been more specific and said the spindle nose diameter is only 1 1/2 inches.

Bob.

I don't think it matters as it's only the same as having a heavy job in it.
I run a 250mm chuck on my 300mm swing lathe sometimes, but only up to around 1000rpm other wise it gets real scary.
I fitted it up to a face plate for those odd jobs that need that size to safely hold something, or need the larger center hole to fit something in. All up with the back plate it weighs around 35kg.
https://www.woodworkforums.com/f65/fi...-lathe-121922/

Dave

Originally Posted by Anorak Bob

the spindle nose diameter is only 1 1/2 inches.

I think I'll withdraw my "a couple of tons" comment. I was thinking about my lathe.

The 8" goes on the 9".
It would be the same thickness as your intergrated 5" only just larger in diameter,it was handy for facing the 120 and 127 tooth gears.
They are a nice light chuck only weighing a few kgs.

Originally Posted by Dave J

I don't think it matters as it's only the same as having a heavy job in it.
I run a 250mm chuck on my 300mm swing lathe sometimes, but only up to around 1000rpm other wise it gets real scary.
I fitted it up to a face plate for those odd jobs that need that size to safely hold something, or need the larger center hole to fit something in. All up with the back plate it weighs around 35kg.
https://www.woodworkforums.com/f65/fi...-lathe-121922/

Dave

I just read your account of the faceplate conversion Dave. The usual innovative approach I've come to expect. Neat.

Thanks Bob,
It's not needed often but has come in handy for a few things have been to big for the 200mm chuck especially with the 65mm bore. Buying a 250mm back plate is hard to come by if not impossible, so the next best thing was to use the spare face plate I had.

When I bought the chuck I couldn't justify buying it only for the rotary table, so coming up with this idea made it worth buying, as it will be more useful to have around. Once I get the D1-4 adapter built for the rotary table, I wont need to take it off the face plate at all.

Dave

Dave's faceplate conversion made me think about another project on my list. I had picked up a Hercus 260 faceplate with the intention of making an adapter to allow it's installation on the 9 inch lathes 1 1/2" x 8 spindle nose. The idea was an offset male / female adapter, the external thread being 1 3/4" x 8. I was talked out of it by Steve Durden at Hercus. He reckoned the offset would provide considerable, potentially harmful leverage on the spindle nose.

How about boring out the hub of the larger faceplate and inserting a 1 1/2" inch internally threaded bush? Could be cast iron, press fit and Scotch keyed. I had thought about sacrificing a catchplate for the threaded bush but it is 5mm thinner than the hub depth of the 260 plate.

BT

Nothing to stop you doing that ,would probably bore it to 2.250",bush and pin and bore and thread to suit.
There are blank castings available to machine yourself from AMH,you would have to check to see if it will take a 1 1/2 thread.

Thanks Peter. I will have a look at Mal's site.

I wouldn't sacrifice your catchplate unless you have another on. As for how your going to do it sounds fine. A tight shrink fit would hold it their as well I think, but something mechanical is always safer.

Dave