Can anybody tell me the minimum thinkness at the top of RIBS in plastic part

Can anybody tell me the minimum thinkness at the top of RIBS in plastic part. We should maintain root thickness 50 to 60% of nominal, but in some case we need to increase the height of rib,that time what should be the minimum thickness we should maintain at the top of the RIB

4 Answers

Rib thickness should never exceed 66% of the nominal wall thickness.if we maintain between 50 to 66 % then we will never have problem of sinkmark...and rib ht should never exceed 3 times the nominal wallthickness

Sorry for the late reply. The minimum thickness as far as I know for the top of any engineering feature should be a minimum of 0.8mm.

min rib height must be btw. 1.5t and maximum 5t according to that you can give your rib thickness w.r.t the draft angle 0.5 - 2 degrees normally

Rib thickness should be 50% of part thickness that is if part thickness is 2.5 mm than rib thickness at the bottom should be 1.25 and by applying a draft to this rib it becomes 0.8 to 0.9 mm at the top