That is a handy feature but your picture is a bit scary looking.
I do hope you worked at very low rpm. Really for a long life with all body parts intact it is better to work at zero rpm with that much material sticking out the back of the spindle. You might get away with it many times but the time things do go haywire can be very exciting as the machines hops around the floor swinging a three feet long metal flail. Having more than about six diameters of un-supported tube or bar sticking out the back end of the spindle is not wise. If you do this regularly you really should build a sturdy frame with a tube that the protruding material is inside. It does not need to touch the tube although a plastic lining is a good idea; the purpose of the tube is just to contain it if it tries to start whipping.