For the spray painters and body repairers out there

Good day all!

Well I'm going to give a front bar repair a crack. I have an OEM 2K bar which has a clean split through the bottom of it:









So my plan is to:
- Clean up the area around the split with a grinder.
- Bond the split together behind the bumper with resin or glue of some sort (any suggestions would be appreciated. I saw this on youtube: https://youtu.be/alyzGrgL6So any thoughts? He uses a combination of superglue and baking soda).
- Heat gun or solder the front (visual side) together to blend the seam.
- Sand until smooth.
- Spray paint (not too sure how I'm going to do this bit, probably with pressure packs. I know a gun would give a much better finish so it might be time to purchase one).

Does all that seem reasonable or have I completely lost the plot?

Cheers guys!

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Even though I'm not a panel beater....
I personally wouldn't use the technique on the video, the plastic he is repairing is of a different composition to your urethane bar
Also, super glue is not waterproof

I believe you need the plastic weld kit with a selection of rods, to suit your bar...they are quite affordable

Also, practice, practice, on similar piece of plastic to your bar....and after you do the repair, i would fill the cavity with the damage with expandable foam

 

Reinforcing the back would be a very good idea I used alloy plate and a 2 part epoxy on my other car the crack will always be a weak point so it will need something strong and a bit flexible behind it.

 

as a panel beater...... the bumpers on a Z32 can not be plastic welded. they are poly Urethane and this material is not like normal bumpers so using heat and a filler rod just does not cut it.

As mentioned there are products out there for joining/glueing my personal favourite is 3M "05887" http://www.shop3m.com/3m-automix-ez-sand-flexible-parts-repair-05887-200-ml.html is to be used with Braces to reinforce the repair.

It is possible to fibreglass as well but the result is not always Ideal. my bumper in my signature is a z32 top grafted to another bumper lower half and fibreglassed together. this has hit a metal leg on a engine hoist in my garage at slow speeds and not broken also was daily driven for8 months with no issues.

 

I hope that jack in the first pic isn't under the radiator support panel!

 

No, under the cross member!

Might you the radiator support is all mashed up, so someone before me has done it!

 

Thank you all for the replies!

I'm going to give bonding it a try as per stumagoo's suggestion.

The paint job on the bar was horrible it just flaked off when I took the bar off. Is there a particular paint I need to use for this type of flexible bumper? I was just going to use normal acrylic.

I'll post in this thread to let you know how I go.

Really appreciate the feedback guys! Thank you.

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the more layers of paint on the bar the more they tend to flake, also our bars are very flexible, and highbuild primer is not as flexible, it can have flex agents added but its still not that great. I am suffering with 1 layer of highbuild and colour/clear starting to peel in areas on my bar - areas with no filler/bog where the bar has been flexed during install. has me really annoyed. yes my bar was cleaned right back to original material before painting

 

Make sure to use a quality plastic adheasion primer under your repairs and paint, on any areas with exposed plastic. Im not sure what the bumper is made of, but im going to assume some sort of plastic.

 

it looks in the pic like its genuine 2k one, in this case its the same material as an FPV or early HSV one ie Urethane. Not PP like most modern bumpers. Our painters never use adheasion primers under their paint but I do under the 3M stuff it comes in the kit but last for ever as its a spray can.
I have seen repairs done without it and they have lasted no issues as well but its good piece of mind, and good trade practice

 

If you're real keen on your aesthetics I wouldn't bother. As far as I am concerned it just can't be done properly. Maybe in a way that will last pretty well, but I've just seen so damn many Z32s with failed repairs it's not funny. Any decent whack going up a driveway and they split right open again.

I spent two years looking for an uncracked NA front bar and finally got one. Stumagoo has a more valid opinion on the topic than I do of course so it definitely can be done with some success, but I'm too picky (and low) to want to worry about it.

 

Thank you for the feedback. I'm all for trying new things, stuffing it up and learning from it. So even if it doesn't turn out perfect I can source a new front bar. I'm going to make sure I brace the inside as much as I can. I have not lowered my car so I do clear most things (unless I'm being stupid).

 

I have used the product brand name Devcon with carbon fibre matting as backing reinforcement, job done & no flex cracking problems after. Painting I used poly Urethane paint.

 

The difference between the 2K bar and the original NA/TT bars is that that the 2K is Polyurethane (PUR shown next to the part number on the bar) whereas the NA/TT bars are Polypropylene. PUR is used in a different, and much lower volume, manufacturing process. The NA/TT original bars are quite a bit thinner than the 2k bar, and perhaps a good repair on those bars is harder to achieve.

The Stillen bars are also reasonably thick PU, and I have seen them bend horribly (off track at Sandown) and still spring back to shape, although the paint may well crack in those circumstances. I haven't seen a 2K bar repair, but I once owned a Stillen bar that was stripped and repaired by a plastic bumper repair specialist which after painting looked perfect. Cheaper than buying a new one!

 

early/original pars are also Polyurethane - all genuine Z32 bars should be the same material

 

There are multiple brands available, I can only comment on the one I have used, and have seen Fibreglas weave (the netting type not the mat) as well as aluminium Mesh and steel strips supplide in kits for the reinforcing, (terison is another brand of repair materials)

 

Thank you all for the info guys!

I can't try is this weekend as I'm off to Kapunda to do timing for the Enduro bikes!

The weekend after that I will get stuck into it. Work always gets in the way of Zeds!

Cheers!

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Update

Good morning all!

I finally got a weekend where I can do some work on this.

The hardest part was removing the left over gaffa tape!! Turps fixed that though.

I used the 3M stuff suggested by Stumagoo and it was fantastic! Very strong and flexible bond with a very short cure time.Today I will give sanding this stuff back a try. On the inside of the bar I placed a fair bit of the resin with fiberglass matting to give it some strength. I guess the test will be when I accidentally run aground!

Pics:







I'll post more when I have sanded the 3M stuff back.

Cheers

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Magic goo

Amazing looking product that, I might have to get some to finally finish off my rear wing!

 

I was very happy with it. I had a mate around just to help me prep and hold it in place, but we did not have to hold for long.

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