Quote Originally Posted by Zeeflyboy View Post
Just out of interest, took your dimensions and applied a load of 200N to mild steel and 6061 alu:


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10mm Steel deflection = 0.06861 mm

25mm Alu deflection = 0.01471 mm


So according to that simulation, the 25mm alu would deflect less.
That is amazing! Totally opposite from what I thoughtModulus of Elasticity. I have the 25mm aluminium, but thought I'd be better buying steel. Excellent news. Thanks for you efforts- totally appreciated.