uhhh...I think that sounds technical, but is not anywhere near reasonable; it's like saying window tint caused the window to crack...plus, the thermal expansion rates will not even be that different since they're both polymers...

Bat's overlays work great, but they do take time to put on...I can see why someone would give it a bad reveiw if they messed it up by trying to go too fast.

 

And there are a bunch of people who never had overlays that developed the cracks as well, so it can hardly be contributed to that reason alone. Polycarbonate has quite a bit of flex to it so cracking would require quite a force from the vinyl

 

Which is exactly why I said it doesn't seem to be a major issue. I've been running Bat's overlays on my car, and have not had any problems aside from the reflector overlays peeling a little. In fact, I wish I put on his headlight overlays when I first got the car, which would have offered some protection to my headlights which are now sandblasted to hell.

I was saying that it is POSSIBLE to have overlays cause stress cracks...is it PROBABLE? IMO, it's not the most likely cause of failure.

 

vinyl and polycarbonate have different thermal expansion rates...very true

vinyl, with the possible exception of some rigid vinyls.. are nowhere near strong enough to crack the pc headlights, regardless of thermal expansion. Since they're overlays.. they're not rigid so for the overlays to cause it is next to impossible.

Molded-in stress is much more likely the cause (in the polycarbonate)

edit: The adhesive used COULD affect the chemical properties of the pc, dependant upon what it is

 

no adhesive used...applied similar to window tint (soapy water)

 

The adhesive is attached to the vinyl, so there is adhesive,just not a very strong one

 

Well I am sold. I think I will get bats smoked overlay, but I cant decide between the 20% or 35%. I drive the car at night more then daytime so Im leaning more towards the 20%. Any input on this?

 

if im not mistaken...the lower the percentage the darker the tint? so Iono what ur going for...darker/lighter? just a heads up bud

 

no I can not. I just said that OTHER people have attributed cracking to the overlays.

 

Your right. I need a lighter tint so it wont affect the lighting at night.

 

Exactly!! This issue has been going on since 2003, even before I started making Overlays for the Z. It even exists on newer 07 models. many say it is attributed to the Lexan Nissan uses for the headlights. Gotta remember also, that the headlight casing itself is very large for the 350Z, so that could be the cause as well. To this day, there is no real proof the Overlays are the sole reason for cracking. Heck, I sported them on my Z with no issues, as well as many other Z owners in our club! If I felt it was, I wouldn't be offering it, as wel as many of the other vendors that make them. If you look at past threads even dated back to 2003, many people who had cracking never had any sort of Overlay on their headlamps.

Bat™

 

My 6/10 tint which is the darker is more aesethically pleasing. Be prepared for a 15% decrease in light output. I also have a lighter 3/10, with hardly, if any affect on light output! I also have yellow and ice blue . Email me to order .

Bat™

 

https://my350z.com/forum/showthread....adlight+cracks

Bat™

 

It could be the Lexan (GE product). I know nothing about the problem people are having.. is it immediately (car new), or after it has aged? It could be a lack of ultra-violet stabilizers in the polymer...which would have to be added seperately during molding.

For those that do not know, polycarbonate is the same polymer used in bullet-proof glass.. it's VERY strong. You can take a 3" square piece that is 1/8" thick.. hit it with a hammer.. it doesn't break.

That being said.. if it is cracking without some sort of impact, it has either degraded in some way (uv light, or chemical reaction) or it has some sort of molded in stress.

 

hey spider310 you could always ask me i got it from Andy from performance nissan and i got it installed at my homies shop called 5thDimensions over at El Monte...his name is Jan!!!




Rene

 

So what's the difference between these and the ones Bats is selling?

 

$20+ difference in price, but they also use a thicker material.

Bat™

 

Is the thicker material good or bad? Sorry I'm a bit of noob when it comes to these things. They do look good though. **Thinking about doing this mod**

 

Good if you want more protection. I feel most people buy the stuff for looks anyway.

Bat™