I cannot understand why these things work. A series of star wheels separated by washers passed too & fro over the spinning wheel - whoever thought of it in the first place I wonder?
Someone voiced a frustration that they couldn't sharpen drills freehand & I saw this in the same place at under £13.00
Drill Grinding Jig SPECIAL OFFER!(Reference #XC317..) Used in conjunction with a standard bench grinder,this attachment gives fast & accurate sharpening of twist drills from 1/8" - 3/4". The diecast body has pre set notches which covers most tip angle requirements.
As to tank straps, several people make & advertise tanks in SEM. No doubt they can help with straps too. regards,