You are not alone there, Cliff,
mea maxima culpa
I might come at a 30sec jaw changeover, but not the 6 mins for the old jaw system, plus another 5 mins finding a dropped screw in the shavings.
That depends on the number of jaw sets you end up with. None of us plan to have the number we eventually acquire...
At last count I think I have 8 sets of Nova jaws. That's 8 x $200 per SN2 chuck = $1600, excluding the cost of the jaws sets.
Had I purchased an Infinity Quick Change Chuck (no jaws) for $349 and purchased the same 8 sets of jaw sizes for the quick change system for what appears to be about an additional $30 per jaw set, then the extra cost of the 8 sets would have been $240 over the cost of the standard jaw sets. That's $349 + $240 = $589
On my reckoning I would have been $1k better off with the new chuck system.
There is a break-even point with fewer jaw sets, for example if you only ended up with three jaw sets then two SN2s plus jaws would cost you about the same as one quick change chuck and three quick change jaws sets. The problem is knowing in advance just how many you will end up with eventually.
There are, of course, other considerations:
- Such a high upfront investment will tend to lock you into just the one chuck/jaw system
- Dedicated chucks will still save more time, but at a higher cost
- Multiple chucks provide more versatility as you can have a number of pieces on the go without removing any of them from their chucks.
- The Nova jaw range has stagnated in recent years. The new chuck system doesn't promise that this will improve.
- And, we are as yet to see how good the engineering is on this new chuck
Teknatool does claim that the new jaws are "much more powerful and capable compared with the older NOVA accessory jaws". If so, that's a good thing, although you rarely hear about any of the current makes of jaws breaking, so perhaps a moot point.
I'll leave others with fewer chucks to consider the economics of the retrofit option, but expect that it will be the way in which the new system will be workshop tested by experienced turners, who already have a lot invested in their current chucking kit and unlikely to go out and buy the higher cost 'starter kit', at least initially, and who will also be the ones who will give the system the thumbs up or down, which will largely determine its future.
PS - issatree, I don't think the retrofit is available for the original Nova chuck, just SN2 and G3.