When the bb marks happen you have to replace the holder and the chuck. You can still buy just the head of the chuck on ebay link below.

Much cheaper than replacing with the carvetight but when you can afford it I would change to carvetight. All your bits with QC holders can be moved over. The decorator bits that are half inch shank just need to have the QC holder removed. The rest need a CT adapter which you can buy from LHR or you can go to amazon and just get a whiteside 1/2 to 1/4 split adapter. That is what I use.

http://www.ebay.com/itm/CRAFTSMAN-CO...owCZuswVk_PCeA