I actually took apart my Hurricane HTC100 chuck to inspect the inner parts. Compared to my SuperNova2 chucks they are built heavier on the scroll gear and pinion gears. I've never had the back off of a Genuine Vicmarc chuck, but can say the Hurricane chucks are a stronger hold than my SuperNova2's. The jaws do not seem to have any creep in them once tightened, where the Supernova's do at times. I always have to go back and check the hold on the SuperNova's, but when I've checked the Hurricanes...they have not loosened at all.
I understand that is about what the Vicmarcs do as well. I've not used the Bulldog chucks myself, but have seen them used by vendors and demonstrators at symposiums. I also do not know who else has a clone of the Vicmarcs, unless it might be Grizzly? [perhaps?] I heard years ago by owners that they have to retighten the jaws on them.
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