Oily film on rear window

rickk

New member
Hi Everyone,



I'm new here, and only recently ran into this board (which is kinda strange since I'm always searching the web for new detailing tips). I must say there's a lot to learn here, and browsing trough the archives will probably keep me busy until the long anticipated big spring detail.. :)



Some more boring background info before I cut to the case, I'm 24 years old, work (Computer network engineer at an ISP) and live in the Netherlands in Europe where detail fanatics (and car nutters in general) are rare and the laughing stock for most of the neighborhood. Anyway, I don't care about it much and try to make the most of my old 1986 BMW 320i (E30 type 1 for the incrowd). It's 18-year old chassis has suffered quite some neglect, but this makes it a great guinea pig to hone my detailing skills. So when I finally restore it to it's full glory, I know how to take care of it.





Enough of that, my question... Since long I have this weird oily looking film on my rear window, in a kind of large 'moire' pattern, which I cannot seem to get off, it's only visible from certain angles and in certain light, but since I'm about just as obsessed as you I don't need to tell you that it annoys me... a LOT.



Anyone any ideas on what this could be and how to get rid of it? So far I've tried Ammonia, White Spirit, A dozen different glass cleaners, MF towels but nothing seems to take real care of it..



I'm afraid tips for specific products won't do me much good, as (much to my frustration) we have a lot less choice and very different brands of detailing products on this side of the lake. A more general indication of 'what kind of product' would be more helpful..



Any general advice on 'how to clean the rear window without demolishing the heater wires or look like a spastic idiot' is much appreciated too.



Thanks in advance,

Rick
 
rickk,



I've seen that same pattern on a number of car windows (if I understand your description correctly, that is); it's very apparent if you happen to wear polarized sunglasses. I've noticed it on many cars, and on the glass windows of some office buildings. Although I can't be positive (and I'm sure someone with more knowledge than I have on the topic will chime in), I believe the pattern is caused by either the UV coating on the glass, or perhaps the glass itself is polarized.



Regardless, I don't think you're seeing a defect; I believe that pattern is by design.



Tort



Oh, and welcome aboard!
 
Hi Rick, and welcome to Autopia! :welcome



I'm not quite sure what pattern you're referring to, but if it's a very faint, but very even pattern of spots or almost a "checker board" type of pattern that is natural as far as I know and I'm pretty sure it is the result of the glass manufacturing process where they fire or temper the glass.



There's nothing you can do about this, but if this really is some kind of oily film that you can move around with your fingers or toweling maybe try lighter fluid. That is one of the stronger cleaners that people have used.
 
Thanks guys, from your comments I believe it's some kind of factory 'coating' too. The window is indeed made of tempered glass, and the 'film' is indeed a checkerboard pattern (only 45 degrees rotated with 'rounded fields') and I don't seem to be able to change it so... it's probably embedded.



Hard to be 100% sure, since you cannot see it from up close.



I don't like the effect, but on the other hand I know it's a not a problem with my detailing skills, so that's good :)



Thanks again,

Rick
 
I've exactly the same pattern you describe on my BMW, rear window. So hopefully it is a feature of the glass used
 
Quote: Oily film on rear window



~One mans opinion / observation~



rickk, welcome to Autopia



For oil etc on tinted glass use Stoners Invisible Glass (window tint (Mylar) safe



For the ‘checker board’ marks….it’s a marking on some tempered glass a result of the process



~Hope this helps~





Experience unshared; is knowledge wasted…/



justadumbarchitect * so i question everything*
 
Back
Top