drilling hard thin plastic bumper

[JohnD]

I have a car where the bumper has a 90degree lip turned over at the edge, which fixes to a similar lip on the wheel arch surround. they were previously attached with a plastic fastener that broke off, breaking the hole, in a bump.

I wantto drill a couple of 6mm holes in the two lips so I can bolt them together

what sort of drill and technique will go through them with minimal risk of tearing or jamming?

 

[Burnerman]

I’d use a 4mm HSS jobber drill bit, followed by a 6 when you are done......pressing down and turning a scribe will give you the equivalent of a centre punch mark to start.
John

 

[just pumps]

High speed with lower pressure on the drill bit.

 

[JohnD]

done it now thanks

when I got it off I found a broken locating dowel, and drilled through that, put a bolt through it to pull them together