Mod materials and machining- screws

This would be a 3M forum post if/when it becomes a reality. What is a good source for small [#2 and smaller] self-tapping screws designed for plastics? I checked McMaster and they don't seem to have screws for plastics. TIA.

Sheet metal screws should be fine for any resilient plastics (delrin, nylon, teflon, polypropylene, polyethylene, polycarbonate, ABS, PVC) but will not give good results in brittle plastics like acrylic, phenolic, or styrene.

Any application requiring such a small screw should be pilot drilled approximately the minor diameter of the screw thread.

Wood screws can be used in softer plastics like PE and PVC, but they have a tapered thread which can cause them to bind up somewhat short of your goal.

Machine screws with self-tapping tips should be avoided for use in plastics. They are too dull to give a decent cut and are apt to congest with their own stringy chips.

Chalo Colina

bump

You are tying to get screws called "BT type" or "type 25", which are almost exclusively used by OEMs. Thus it's difficult to find a retailer for them, especially in uncommon sizes.

The only difference between a type 25 screw and a sheet metal screw is the point, though.

There are a few #2 sizes of other kinds of plastic-specific screws here and here at microfasteners.com, who seem to deal in retail quantities (which is the rub with this sort of hardware).

This wholesaler offers "samples" of their wares, which might be enough to meet your need.

Chalo Colina