Originally Posted by
jboggs
> Frankly, the whole structure strikes me as inadequate. (You wanted honesty, right?) It may stand up ok if everything is in perfect alignment, but I don't want to be standing near it with a 900 lb load at the top of the stroke when it starts to deflect just a little. Didn't you say in the beginning that you were concerned about forktruck hits?
> Have you thought about what would happen in the case of failure? You need to insure that the possibility of human injury is well understood and minimized.
> Is your footprint size limited? I would lean toward a larger turntable if possible.
> Have you looked at jib crane structures? That's almost exactly what you are building here. They come pre-engineered for larger loads. Could you buy one and modify it? The difference is that they have a fixed center structure with an outer frame that rotates around it. That means the main moment load at the bottom is absorbed by a fixed structure rather than a rotating bearing.