• Bottom of expansion tank

    This is the cover of plastic water tank for a branded automotive company. The material is PP. The part features with a long BOSS and round undercut of 1mm. The BOSS structured with a round pin on the cavity followed by forced demolding. In most shops, slides are usually used to form the feature but this is a waste of money considering the quantity of the products. So we use insert to make the BOSS. Since undercut is to assembly the water tube, we have to keep tight control on the undercut measurement. After forced demolding, the size of would become smaller. So we have to check the dimension of of undercut after trial and then use mirror EDM to machine until we get the right size. This process usually has to been repeated over 2-3 times. For the water tank, the key technology is the part must be flat…

    plastic products October 31, 2019