Just bought a 14" four jaw chuck that just fits my nominally 14" Celtic Mondiale lathe with an L0 spindle. The chuck is used, and it looks like the previous owner didn't bother to clean the spindle and bore many times. The chuck body is a one piece casting. The L0 taper bore has lots of compression divots from compressing chips between the bore and spindle. I suspect that if one had a "master" L0, some dykem to expose high spots, a little judicious scraping would make the thing right. The chuck is VERY heavy or I would try removing the key on the spindle and using that, but the chuck body with all the moving parts removed still weighs 80 lbs. Too much for this 78 yo. to handle. I have a home built articulated boom crane I use for mounting my chucks and mill vise.