In reply to Reach>Talent:
Very small crimps seem to be easily broken. I found that small crimps and finger pockets were best made on a much larger base, say 6" diameter and at least 1.5" thick. I cut the base out and drilled the holes for the bolt and washer, then I used a round surform to make a couple of horizontal grooves above the bolt hole. After sanding it all down it proved to be a very useful hold, allowing feet to be placed on the more robust outside edges and preventing the more delicate crimp/groove from being kicked off. Quite good for side-pulls when the groove is placed vertically as well.
I need to change my set-up so if you come up with any stunning designs please share.