Shrink Rate (Explanation for Tolerance)
There are many factors that contribute to silicone having a varying shrink rate from 3% to 5%. These include silicone durometer, raw mixture, part design, environmental conditions, molding process variance, position of part in mold, and post curing. Abatek uses 20+ years of manufacturing experience to control these variables so that keypad production is consistent.
Because of the variable shrink rate, Abatek is limited to how tightly part dimensions can be held. This also limits how tight assembly stack-up tolerances can be kept, however there are many tips & tricks on this page that explain good assembly design practices.