Ruined my motorcycle screen through petrol: can it be undone? 1

[RuudMuschter]

Dear Friends,

Recently at the petrol pump I accidently sprayed a lot of petrol over my motorcycle screen. It is of a plastic of sorts. There are now milkywhite stains all over it.

Is there a method to undo this or to mask it in any way?

Thanks for your suggestions.

Greetings,


Ruud Muschter
the Netherlands

 

[Demon3]

Probably not. Your screen is almost certainly made of polycarbonate which has excellent impact resistance. Exposure to solvents ruins the plastic and it cannot be undone. Even if you polished it and somehow made it look fine, it would not be safe to use it as the plastic would be very weak. This is the same reason you cannot put stickers on motorbike helmets. They are also made of polycarbonate and exposure to the traces of solvent in the sticker adhesive weakens them so they no longer protect you even though they look fine. Sorry, you will need to buy a new one.

In case you're interested, the thing you just suffered from is known as "environmental stress cracking".


There is not any memory with less satisfaction than the memory of some temptation we resisted.
- James Branch Cabell

 

[MikeHalloran]

Do yourself a favor; discard the screen.

Do someone else a favor; cut it into pieces before discarding it, so it can't be reused.

Actually, now that it's been sensitized, a few light hammer blows might cause it to crumble ... which is why you should discard it.



Mike Halloran
Pembroke Pines, FL, USA

 

[asterladybug]

if you want to avoid it nex time, ask for a hard coated version.
its surface than has a superior resistance to chemicals too.

PS.: these white stains are in fact microcracks. if you tend to break the shield, make sure you wear eye protection

 

[wringme]

Don't be to quick to assume the winsscreen in Polycarbonate. If it is, it would most certainly be coated with a UV protective coat as PC will break down under UV rather quickly. No reputable manufacture would put an uncoated PC into an application of that type where impact would be an issue. More likely it's acrylic, a product which is used extensively in this area and is actually used in aerospace as a protective laminate for polycarbonate canopies - such as the F-16.

If it is acrylic, it can possibly be buffed out - buff in a wide ranging area so as not to enduce opotical distortion. The material properties will not be degraded and if it comes back to a smooth and glossy surface, you will be none the worse off.

wringme

 

[patprimmer]

wringme

You are wrong on several points.

Polycarbonate has fair resistance to UV. This can be improved considerably by adding UV stabilisers to the resin.

Coatings on polycarbonate are mainly to improve scratch resistance. The scratch resistant coating also sometimes includes a concentrated UV absorber. It also improves chemical resistance.

If the scratch resistant coating had done its job, the screen would not be crazed. As it is razed, it is ruined, even if the marks do polish out, as the impact resistance will be severely compromised.

Acrylic has a brittle break and is no longer normally considered suitable for motor cycle screens.

In my opinion, scratch resistant PC followed by high impact acrylic are the materials of choice



Regards

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