Having made a Longworth chuck from acrylic, we’re now investigating a cheap and easy way to grip material for turning on a miniature desktop sized lathe.
The Longworth chuck works well in principle but locking it could be difficult. It’s a nice bit of engineering and sliding the jaws open with a simple turning action is quite satisfying, but getting it to stay locked so that it’s strong enough to grip some material while spinning in a lathe might be quite tricky.
So far Robot Steve has come up with some sort of torsion spring to keep the jaws clamped around the piece. We’ll give it a try, but we’d also like to try a lower-tech solution:
At BuildBrighton, we’ve access to a Myford lathe. So machining a piece of rubber with a number of decreasing sized circles shouldn’t be too difficult. Exactly the same “chuck” could be mounted on the motor part of a miniature lathe, and also on the free-spinning end, and the two ends drawn together using a threaded rod (or similar) on the base.