fibre glass paste will work but only very temporary as composites will not permanently stick to thermoset plastics.(i.e ur bumper) best advice i can give ya is to take off the bumper, sand off any paint around the cracked area, (leave the bit around the headlamp if its still textured), bridge the cracks from behind with glass fibre paste without any going thru the gap, then blend the crack over with polyester body filler. ur gonna need p38 an p40, im not sure what one is which but one is fibre glass paste and one is smooth body filler, then take some time smoothing over the crack, then prime and paint the area locally. if ur bumper is fibre glass anyway ur laughing cos it will bond on fine. but origonal bumpers are plastic. good luck man.

I urgently need some advice before i take my car to trax this weekend. Now its very near & unfortunetely i don't have the time or money to buy a new front bumper. So i need to repair this one as much as possible myself this week. It is cracked fairly badly underneath the left headlight and again underneath the middle mesh section. Then it has lots of hairline cracks all around the left side and around the fog light bit. So i was wondering can i go to my local halfords to buy some fibre glass filler and then carefully paint it myself?
Ive heard of p 38 but i haven't got a clue what it is!
Please help me soon.
Cheers Ness :)