Alan said, >"I am surprised no-one has suggested making one. > They are easy to make, and can be built from castings or stock material. > > In that way it could be the size one wants and as rigid as required." One could also make it air actuated, but of course that would probably cause a few cases of "M-1 Thumb" and those are not nice. "M-1 Thumb"? ask any GI from WWII or the Korean mess and they can tell you all about it! Jesse the redneck from Tennessee MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.