Bumper Repairs

myredmx5 · Postby **myredmx5** » Tue Aug 25, 2015 11:17 pm

My bumpers need repair.

Is there a section on this forum that can walk me through this job.

I am keen to learn to do it myself and not just farm it out.

Crapweasel · Postby **Crapweasel** » Tue Aug 25, 2015 11:25 pm

Depends on what repair you need.

If you have a pushed in bumper, you can heat it up (heatgun) and push the dent back out from the inside, but you'll need to assess the paint.

If it's gouging, then you'll need to look up car dent repair on Google, and select whatever applies for your situation for plastic scratch repair.

Can't offer much else without more info sorry.

myredmx5 · Postby **myredmx5** » Tue Aug 25, 2015 11:51 pm

The repair required is splits and/or cracks.

hks_kansei · Postby **hks_kansei** » Wed Aug 26, 2015 10:15 am

Paint splits and cracks unfortunately are a matter of just sanding it back and painting it.

If the plastic itself is cracked you're best to patch the area from the rear, using another piece of plastic with a fair bit of overlap onto the non-cracked areas.
Clean the area thoroughly, i'd even give it a sand down to rough it up a little.
Then glue the patch on the back with a strong adhesive like araldite or something.

Once that's all set you can then move to the front, the visible area of the crack.
This should just be as simple as sanding the paint away from the area and then using a tiny drill bit to drill a hole at the very end of the crack (both ends) Drill just through the bumper and not into your patch on the back.
The drill hole will help to prevent the crack growing in future.

then it's just a matter of buying some form of filler and filling the crack and holes, sand, paint, etc.

The patch on the back is to give it some support and strength so that as the bumper vibrates it doesnt just crack in the same place again.

Danny · Postby **Danny** » Wed Aug 26, 2015 11:16 am

There's a good product, Fusor 152, secifically for repairing cracked and broken poly bumpers. It maintains the flexibility, can then be sanded and painted same as the original bumper. Quite a few guides on the web.

myredmx5 · Postby **myredmx5** » Wed Aug 26, 2015 6:43 pm

Thanks hks_kansei

myredmx5 · Postby **myredmx5** » Wed Aug 26, 2015 6:43 pm

Thanks Danny

hks_kansei · Postby **hks_kansei** » Thu Aug 27, 2015 10:59 am

I'll just add, that if Danny's stuff has flex etc it's probably the better option than my suggestion.

I've done mine with success on a bumper, but it also hasn't seem much vibration etc. If you drive where you can expect lots of vibration (dirt roads, or Sydney's roads that look like they came from London after the blitz) the filler may split at the edges.

Mr Morlock · Postby **Mr Morlock** » Thu Aug 27, 2015 1:08 pm

I have never repaired a bumper but a product like Fusor 152 looks to be very good. It does underline that body repairs are often quite laborious and seemingly only as good as the preparation and choice of the right materials. I bookmarked the Fusor product but I noticed that 3M does one as well - maybe brand is not critical but right type of product is. Thanks for the tips

taminga16 · Postby **taminga16** » Thu Aug 27, 2015 8:48 pm

We have been using this product for general structural repairs in plastics, http://www.rapidfixaustralia.com.au/about-rapidfix/. It is no fuss, long lasting and very effective, do not be tempted to use too much on a repair.
Greg.

hks_kansei · Postby **hks_kansei** » Fri Aug 28, 2015 10:53 am

I've used a similar thing with some camera repairs.

Superglue and Bicarb react to form a plastic. In my case it wasn't hard enough to do what I needed it to, so I can only assume that either my ratios were off, or that the store bought product has some other additives to make the product work better.
I suspect it to be a bit of both sides.

Just don't touch the stuff while it's curing, it generates a fair bit of heat for such tiny amounts.