We have a collection at the museum, a 160mm Chinese 4 jaw independent, a 6" lightweight four jaw independent by Toolmex, 2 x 5" Pratt Burnerds 3 jaw scroll, a 125mm Chinese 3 jaw scroll, a 160mm Indian 3 jaw scroll, a Burnerd 6 3/4" three jaw scroll serrated jaws, a 4" Pratt Burnerd 3 jaw scroll. Also, an 80mm three jaw scroll (ex my mini lathe) on a revolving MT2 for the lathe tailstock. Three faceplates and the original Smart & Brown collets.
The all get regular use except the 80mm, we haven't found a job for it yet. THE 6" 4 jaw and one of the PB 5" are also used on a rotary table. There is also an er25 collet plate that fits on the lathe.
The 125mm Chinese chuck and the 5" PB's would seem the same, but the larger jaws in the 125mm give a welcome overlap in the work they can hold, especially with the external jaws.
As for your choices, make sure you keep the best ones and be sure that there is some overlap in the holding capacity. It sounds that the griptru might be the one to go, have you tried any of the other PB jaws in it?
Edited By old mart on 25/04/2022 21:14:12
Edited By old mart on 25/04/2022 21:17:25