Plastic Products and Mold Design

Hello Tim Hilliar,

I think self tapping screw is OK. I would add small guiding holes (1ºdraft, rounded ends) in the screwing points in order to prevent unnecessary stresses (and save some plastic).

Did you think about overmoulding the filter?

Good luck!

Thanks

Screws are used all the time in automotive. Usually washer head hex nut or torx. Ensure there is a full depth pilot hole and gussets on the screw bosses over 1/2" tall. For internal threads there are threaded inserts, they add to the production complexity.

I am modeling electronic cash registers. Self-taping screws are traditional for this type of products. www.incotex.bg

Hi Tim,

Like most things it depends.

If you want a high quality part you will probably want to use the over molded threaded inserts. These are not as difficult to add(my best assumption of were you planning to add the nut) to the process as an operator/robot will add these into the tool between each cycle with little issue.

If you want a lower/cheaper part the self tapping screw will work. My

suggestion will be to tapper these cores to help secure the screw as you

will be dealing with vibration on this part.

Hope this helps.