Best way to fix cracked plastic?

[E30REDD]

Washing, sanding, putty then paint?

[suedenim]

This episode of wheeler dealers shows a good way to repair abs plastic, although yours looks like it could be fibre glass. The main principles would be the same though. What bumper is that?

[E30REDD]

This episode of wheeler dealers shows a good way to repair abs plastic, although yours looks like it could be fibre glass. The main principles would be the same though. What bumper is that?

Okey thank you, I will have a look at the link.

It's the iS front, fibre glass

[DanThe]

Just get another bumper

[E30REDD]

Just get another bumper

Why would I when the rest looks good!

[DanThe]

Just get another bumper

Why would I when the rest looks good!

To put it in laymans terms,

"cause itz fcuked innit"

[Brianmoooore]

The way to repair ABS is to 'stitch' weld it at the back with a soldering iron, using the same kind of action as you would with a stick welder. Once it's tacked together, you reinforce the back using a proprietary type of body filler made for the job with reinforcing fibres in it.
If the joins need to be invisible, you then grind out a small vee shape along the joins, and fill.
If it's fibreglass, then it's aftermarket tat, and is probably best binned anyway, but if you insist on repairing it, the technique is similar, other than you can't stitch it first, and you do the reinforcement with fibreglass mat and resin.

[E30REDD]

The way to repair ABS is to 'stitch' weld it at the back with a soldering iron, using the same kind of action as you would with a stick welder. Once it's tacked together, you reinforce the back using a proprietary type of body filler made for the job with reinforcing fibres in it.
If the joins need to be invisible, you then grind out a small vee shape along the joins, and fill.
If it's fibreglass, then it's aftermarket tat, and is probably best binned anyway, but if you insist on repairing it, the technique is similar, other than you can't stitch it first, and you do the reinforcement with fibreglass mat and resin.

So bumpers on E30's that are made of fibre glass are cheap shit?

Well, if it's easy and inexpensive to repair it. Why not? The car will be worth more if it looks proper.

[suedenim]

So bumpers on E30's that are made of fibre glass are cheap shit?

Well, if it's easy and inexpensive to repair it. Why not? The car will be worth more if it looks proper.

To put it mildly, aftermarket fibreglass bumpers are way poorer quality compared to the originals. It would cost you around the same to buy an original when compared to time and money repairing, an iS splitter will set you back more though. However, if you want to retrain the look that the aftermarket gives use the techniques in the link - drill a hole where the crack starts, vee the crack and even drill holes along either side of the crack to create a stitch possibly, although use a fibreglass repair kit as brianmoore suggests.

[E30REDD]

So bumpers on E30's that are made of fibre glass are cheap shit?

Well, if it's easy and inexpensive to repair it. Why not? The car will be worth more if it looks proper.

To put it mildly, aftermarket fibreglass bumpers are way poorer quality compared to the originals. It would cost you around the same to buy an original when compared to time and money repairing, an iS splitter will set you back more though. However, if you want to retrain the look that the aftermarket gives use the techniques in the link - drill a hole where the crack starts, vee the crack and even drill holes along either side of the crack to create a stitch possibly, although use a fibreglass repair kit as brianmoore suggests.

Okay

What do you mean by iS splitter?

[DanThe]

dont any1 no how to fiks motosport bumperzz?



diffin ready innit

[sweep]

drifter =?

[B7]

The way to repair ABS is to 'stitch' weld it at the back with a soldering iron, using the same kind of action as you would with a stick welder. Once it's tacked together, you reinforce the back using a proprietary type of body filler made for the job with reinforcing fibres in it.
If the joins need to be invisible, you then grind out a small vee shape along the joins, and fill.
If it's fibreglass, then it's aftermarket tat, and is probably best binned anyway, but if you insist on repairing it, the technique is similar, other than you can't stitch it first, and you do the reinforcement with fibreglass mat and resin.

Nearly there, you could try to plastic weld it properly. Stitch welding the back and then p40'ing it leaves it weak. You need to seam weld ABS as a slight knock will rack it. You need to seam weld both sides to full penetration to get full strength.

But re this thread, Come on guys, if the gent wants this bumper then lets try to help him instead of telling him what he's got is shit. Which 90% of us may thnk it is......

If it's fibreglass (which it looks to be), drill two holes either side of the crack and tie wrap it tightly together. Drill another hole at the end of the crack to stop it going any further.
Grind the back out and reinforce it with fibre matting and resin untill stong.
Once set remove the tie wrap and working from the front, grind out the crack in a vee and float it with resin. Some would grind it right out and repair like the back but on the old Lotus's I use to be involved in, it makes the front too bulky. Floating resin in there allows you to build it up. Once happy, flat it back with production paper and a light coat of filler / stopper and you should be close to paint.

If it's ABS plasting use the same drilling and tie wrap trick and then buy / borrow one of these:

http://www.ebay.co.uk/itm/MicroWeld-80- ... 1657wt_976

If I'm repairing a bumper, rather than use the fibre rods they supply (which are actually better than I thought they would be) try to source some plastic of a similar bumper and use offcuts as filler weld.
Grind a vee out of the back, and preferably using the type of ABS plastic as a filler, fuse the two sides of the crack together.
Then remove the tie wrap and fill the rear of the three holes again with the same stuff.
Move to the front and grind a vee out and fuse the two sides together. You should be deep enough to be utilising what you've done to the rear so you have effectively had complete penetration.
Scurf back the front and finish to paint.

Job jobbed.

When I bought my 530 sport off Barrold, it had a cracked front bumper. I never had a decent photo of the crack but this is semi prepped and I've shown the extent of the crack on this shot:





And when it came back from paint it looked like this :





And I did an e36 MTech front bumper the other night off a breaker I have for the buyer.

[DanThe]

Nice job Trev, but as its a fibregash bumper the op has, and a good genuine bumper can be had for £20 I thought it was a no brainer?
You would spend more in materials to fix the damaged bumper

[E30REDD]

Thank you B7!

Nice job Trev, but as its a fibregash bumper the op has, and a good genuine bumper can be had for £20 I thought it was a no brainer?
You would spend more in materials to fix the damaged bumper

Oh, I thought these bumpers cost at least £100. If they cost £20 then they're absolutely not worth to fix. Where can I get one of these for £20?

[DanThe]

If you scroll down the main forum page you will find a section called "Wanted E30 parts"
Click it and start a thread for your wanted parts

[B7]

Thank you B7!

Nice job Trev, but as its a fibregash bumper the op has, and a good genuine bumper can be had for £20 I thought it was a no brainer?
You would spend more in materials to fix the damaged bumper

Oh, I thought these bumpers cost at least £100. If they cost £20 then they're absolutely not worth to fix. Where can I get one of these for £20?

Ahh. I was thinking this was possibly some aftermarket "Sick Phat" item, that the OP wanted to keep. Not a standard facelift look.

I have standard non M tech genuines in stock. And yes, they are £25 an end.

[E30REDD]

Thank you B7!

Nice job Trev, but as its a fibregash bumper the op has, and a good genuine bumper can be had for £20 I thought it was a no brainer?
You would spend more in materials to fix the damaged bumper

Oh, I thought these bumpers cost at least £100. If they cost £20 then they're absolutely not worth to fix. Where can I get one of these for £20?

Ahh. I was thinking this was possibly some aftermarket "Sick Phat" item, that the OP wanted to keep. Not a standard facelift look.

I have standard non M tech genuines in stock. And yes, they are £25 an end.

Okay, but I guess shipping it to Finland would cost a lot since they are kinda big.

[B7]

Not sure to be honest but I don't think would cheap no