Hook and Hanger Marks

Question:

I am the operations manager at our plant. We are having difficulties on our paint line. Our painted parts have shadows—areas that are not painted where the hooks and hangers shield the parts from paint on the paint line. Our quality control and manufacturing people are discussing what should be allowed and what should not. I would like to know if there is a standard for hooks and hanger marks in the industry, such as, what is allowed and what is not allowed. K.N.

Answer:

Although I am sure they exist, especially in industries such as automotive, appliance and office furniture, I don’t know of any published standard for hooks and hanger marks on painted products. Sales, engineering and quality control departments in the aforementioned industries generally establish these standards for their own products. Unless you have access to these standards, you will have to establish your own. What is allowed and what is not allowed depends on acceptance by your customers, the value of your products and the final location of any hook and hanger marks on your products. Correct hanging of parts to be painted is the key to solving the problem. Correct hanging is dependant on the location of holes for hanging the parts. These holes should be located so that the shadow caused by the hooks or hangers are not visible when the products are assembled.