Drill and screw through plastic
by precious-plastic | Source: Precious-Plastic-Community-Platform
When screwing through plastic, several factors have to be taken into account. Here we will explain a few steps and tips to make the job easier.
Step 1 - Stay safe
When talking about safety we are only referring to precautions about working specifically with plastic, as it’s our thing. We assume that working with the drill press needs a certain level of expertise so please take all the precautions related with how the tool works.
When using the drill, special attention must be taken when working with plastics such as PS or ABS. There is a danger of overheating the material locally and accidentally releasing bad fumes. So in order to work safer make sure to use a gas mask with ABEK filters to prevent inhaling possibly toxic fumes. An easy way to identify them is to check if the filter has four colour lines (brown, grey, yellow & green).
Step 2 - Collect the valuable offcuts
Processes like drilling create a lot of small plastic pieces. Try to collect all the offcuts you generate since they can be used perfectly as pellets for your further projects - and that also saves them from ending up as microplastic in the environment!
Step 3 - Pre-drill
In order to avoid any deformation and the possibility to break the piece we recommend to pre-drill a hole with a slightly smaller diameter than the screw (e.g. for a 3mm wood screw you’ll pre-drill a 2mm hole). This is especially needed for holes which are closer than 8mm to the edge and when working with PS in general.
The best way to drill through plastic is a combination of a metal drill bit and setting the machine at high speed. Special attention while working with brittle plastics like PS since one of the sides generally ends up chipped.
Step 4 - Countersink the hole
Depending on the type of screw you choose you can use a countersink bit to countersink one side of the hole.
Step 5 - Threading the hole
When working with bolts, you might want to thread the inside of the whole. Plastic materials fully embrace this technique.
For tough materials like HDPE and PP this is not urgently needed though, as just screwing in the bolt is often enough to hold it pretty tight.