Acetal is “snappy”.
Here I’ll share with you validation procedures that the part will undergo. In general terms, we need to ensure a few things for this to work. 1) Ensuring that the part does not exceed (in any ways) the Ultimate Tensile Strength(110Mpa) anywhere in the clamping process i.e the ultimate TS is when the part shatters in little pieces, or the moment when you get mad at me loll. We also need to ensure that it stays below its Yield Strength (64 Mpa) when in operation. We don’t want the part to be living under excessive stress during all of its life. Within the range is perfectly fine, but not above!
Lastly, it need to provide a good clamping pressure so when the wheel rotate and X and Z velocities changes, the cap remain where it should. Keeping a pressure above 100Mpa is the target here so watch your fingers when you snap them into place, it’s going to hurt-a-little if you get your skin trapped between the wheel and the cap
Although, for a light 77grams cap, I think that 50 would be more than sufficient – but let’s not take any chances!
Side note: for anyone familiar with CAE, I am solving this with SOL 601,106 Advanced Nonlinear Statics (using a 0.2 as coefficient of friction, 2D CQUAD4 mesh and a RBE2 connector for the enforced displacement). Nastran 11 Solvers, what else better
^ Not 100% completed but going into the right direction! Nasty work I tell ya but still fun to do. Sometimes I think my fellow Chinese friends have the right way of doing things = "looks good, then its okay lolll"