BBC news, I am not the FEA guru but I have done several FEA models in few FEA programs.

Your model is very simple, just constrain one end of the beam (depends if it is shell or solide model - solid model gives good answer , I thnink hex is solid element). Put force on other end. You will get decent stress and displacement. There may be so many java template for cantilever beam, you can check your answer or you use hand calculation to check the answer. Instead of putting 1lb on each node, try to put 1 lb only in one node. Or try putting 0.0001 lb. If still you see large displacement, check your nodes, there may be dis-connection or it may not be constrained properly. Try merge nodes, it may work. Magnify your model and check how nodes are connecting. How elements are laying. Try to make very very simple beam lets say 1/2 inch wide and 1 inch long. and put force at the end. The best way to defug FEA model is make it simple and simple and try to sort out the issue.

I dont have time otherwise I would go to your so called free internet program. But i guess you may be able to run this model.

Good luck.

Nepalean

Bythe way what is the input file for calculix? May be I can make a model but I dont like to do that since you are a student and thts not ethical.

Constraint all one end. put force on other end. Try to use with small load. May be put a point load, put only one end.