I always like to err on the side of holding things too tight rather than too loose but notice I did give you a range; 3" for about 1300 lbs and 4" for about 2300 lbs.
The lever suggestion is also very viable and you can also get force multiplication by using a toggle clamp or a sliding wedge. These are more complicated to build but when your volumes increase it becomes worthwhile putting in the extra effort on the fixturing to reduce the reloading time.
An advantage with both the toggle clamp and wedge is that they can be self locking so if you lose air pressure you do not get parts flying around. In this case you need a double acting cylinder because force is necessary to unlock.
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An open mind is a virtue...so long as all the common sense has not leaked out. |