Filling in a bumper hole..

[JonnyFive]

So, on my MX5 I've removed the front number plate holder.. Which was held on by two plastic clips through holes in the front bumper. What is the best way to fill these holes before I get it resprayed?

Could I use some Sikaflex to glue some plastic/card to the back of the bumper and then use some filler to build the hole out and then skim flat?

EDIT: Just to say, the holes are less than the size of a 5p piece, not massive.

Edited by JonnyFive on Sunday 18th March 10:30

[snuffle]

Filler in a hole is liable to crack.

clean and lightly sand front and back of the bumper 180ish grit

slightly countersink both sides with the same paper.

loosely cover the rear of the hole with masking tape.

fill hole with 2 pack epoxy resin, areldite or similar

use a piece of plastic (bottle lid are good) taped across the outside of bumper to hold resin in place while it cures, this will also give a smoother face(less sanding).

by countersinking both sides the resin will be less likely to crack out.


ETA.
http://www.ebay.co.uk/itm/Polyurethane-Semi-Rigid-...

maybe better than areldite.

Edited by snuffle on Sunday 18th March 12:08

[JonnyFive]

Excellent, thanks very much.

So no need to put something across the back of the bumper? Just sand it, put some of this stuff in the hole and then put some plastic over it and leave to dry?

Would it be worth a skim of filler over the outside when it's dry or no need?

[snuffle]

Some people use a plastic mesh across the rear on larger repairs

and yes you can use filler to smooth the front face, just let the plastic repair material cure fully as it can rip out when sanded if not fully cured.

Fully hard is not fully cured.

24 hours can be needed if the temp is lowish.

[snuffle]

http://www.youtube.com/watch?v=gMr9aJ-j0NQ

[JonnyFive]

That video is excellent, thanks for that!

[7even]

Methods like this should be used with caution, you need to make sure absolutely no water what so ever can enter the repair from the back, other wise the repair wont last. saying that it is a repair and not a new bumper.
Or you could just get the shop thats doing the respray to do it?

[snuffle]

skim across the rear of the repair area with sikaflex or similar to reduce the possibility of moisture entering the repair area.

[JonnyFive]

7even said:

Methods like this should be used with caution, you need to make sure absolutely no water what so ever can enter the repair from the back, other wise the repair wont last. saying that it is a repair and not a new bumper.
Or you could just get the shop thats doing the respray to do it?

I've always tried to do everything myself on my car, including painting parts.. Which came out well, but they've only been reasonably small parts so getting the bumper sprayed.. I'll do everything else myself.

snuffle said:

skim across the rear of the repair area with sikaflex or similar to reduce the possibility of moisture entering the repair area.

Good thinking, will do that