@wonkipop I went out to the ol 74 1.8. All of my glass is Delodur-1 clear if that helps the data collection. My front windshield (windscreen) is aftermarket DOT 177 M3 (L-N Safety Glass S.A.DE C.V. OF MEXICALI, now owned by Pilkington Glass it seems)

Hi, here is what the 'squiggle wave' means

(from " Ordinance on the testing and approval of the design of vehicle parts and their marking (Vehicle Parts Ordinance - FzTV) " (Germany, translated)
.
.
.
" § 7 test marks
(1) The test mark consists of a wavy line of three periods, one or two code letters, a number and, if necessary, additional characters. The code letter designates the type of vehicle parts according to the following list:

D
for safety glass and films for application to vehicle windows
E
for tachographs
f
for overrun brakes and parts thereof
G
(dropped out)
K
for lighting equipment
L
for anti-skid devices
M
for vehicle connection devices
R
for tires
S
for heaters
W
for warning devices with a sequence of sounds of different fundamental frequencies (operational horn).

If vehicle parts from two different types are approved together, the test mark contains both code letters. The test mark is assigned by the Federal Motor Transport Authority based on the model in Appendix 3.
(2) If the approval procedure has been carried out under conditions that the Federal Republic of Germany has agreed with other states, a test mark must be assigned for the relevant vehicle part. This vehicle part must not be approved by another contracting party on the basis of the same conditions, nor may it have been assigned a test mark. The test mark consists of a circle containing the letter 'E' and the code 1 for the Federal Republic of Germany, as well as the approval number. The latter must be placed outside the circle. Otherwise, the Federal Motor Transport Authority determines on the basis of international agreements how the test mark is to be arranged. It supplements the test mark in compliance with international agreements if this is necessary to avoid misunderstandings.
(3) Test marks that were assigned prior to November 19, 1998 on the basis of type approvals and contain code letters in accordance with Appendix 2 Part 2 may continue to be applied until the respective type approval expires and remain valid unchanged; this also applies to the distinguishing letter E for tachographs, checked by the North Rhine-Westphalia State Calibration Directorate in Cologne.
(4) The assigned test mark must be affixed to each part of the vehicle corresponding to the approved type in the prescribed arrangement in a legible, permanent and identifiable manner at any time; this also applies to the vehicle part attached or installed in accordance with the type approval."

Regards
Norbert

edit: list of test centers added
Annex 2 Part 1 (to Section 5 Paragraph 1 Sentence 2 Nos. 1 and 2, Section 7 Paragraph 3)
Responsible test centers for certain vehicle parts and their previously assigned code letters
Source of the original text: Federal Law Gazette I 1998, 2153


Previously assigned code letter
testing center
part type for which the testing centers were previously responsible
D
Materialprüfungsamt
-
Sicherheitsglas including films for application to vehicle windows
North Rhine-Westphalia
44285 Dortmund
E
TÜV NORD Mobility GmbH & Co. KG
-
Tachograph
IFM - Institute for Vehicle Technology and Mobility
At TÜV 1
30519 Hanover
F
RWTÜV Fahrzeug GmbH
-
Overrun brakes
Adlerstraße 7
-
Facilities for connecting vehicles
45307 food
G
State Material Testing Institute at the University of Stuttgart
-
Seat belts
-
Restraint devices for children in motor vehicles
PO Box 80 11 40
70511 Stuttgart
K
Light Technology Institute of the University of Karlsruhe Test center for light technology equipment on vehicles
-
light technology equipment
Kaiserstrasse 12
76128 Karlsruhe
L
Examination commission for anti-skid devices at the Federal Motor Transport Authority
-
Anti-skid devices
24932 Flensburg
M
TÜV AUTOMOTIVE GMBH Group of companies TÜV Süddeutschland area Munich
-
Facilities for connecting vehicles
-
Overrun brakes
Daimlerstraße 11
-
Warning devices with a sequence of sounds of different basic frequencies - emergency horn
85748 Garching
N
DEKRA Type Testing Center/ Technical Service of DEKRA Automobil AG
-
Heaters
-
Skid protection devices
-
Panes made of safety glass
Bernhardstrasse 62
-
Overrun brakes
01187 Dresden
-
Facilities for connecting vehicles

-
Warning devices with a sequence of sounds of different basic frequencies - emergency horn

-
Seat belts

-
Child restraint systems in motor vehicles

-
Tachographs and control devices
S
testing center for vehicle parts in the research institute for automotive engineering and vehicle engines
-
heaters
Pfaffenwaldring 12
70569 Stuttgart
Unofficial table of contents
Annex 2 Part 2 (to Article 7 Paragraph 3)
Code letters that are no longer assigned
(Source: BGBl. I 1998, 2154)

code letter that is still valid and is no longer assigned
testing station
part type for which the testing station was responsible; Reason for waiving jurisdiction
A
Technical test center for motor vehicle traffic of TÜV Berlin-Brandenburg e.V.
Sidecars of motorcycles;
T
all other technical test centers for motor vehicle traffic
sidecars no longer have to be of officially approved type according to § 22a paragraph 1 StVZO.
B
Physikalisch-Technische Bundesanstalt in Braunschweig
tachograph; Responsibility was transferred to the State Calibration Directorate of North Rhine-Westphalia (code letter E).
C
Technical test center for motor vehicle traffic at the Technical University of Berlin in Berlin-Charlottenburg
- heaters
- Overrun brakes
- Devices for connecting vehicles;
Takeover by DEKRA e.V.

thank you
@nordfisch

OK, finally went out and took a picture of mine. March 1970 -6. Original glass unless it was replaced 45+ years ago.
Click to view attachment

ripper mate
thanks for posting that.
the old time machine.
you get to go to year zero over in the originality thread.

Stoddard is selling Porsche branded windscreens, with a modern brand. I’m restoring a six, but I’m not sure if it’s really much of an improvement over the XYG aftermarket that’s a third the price.
Click to view attachment

My last replacement was sourced from my local Porsche dealer and is identical to the Pilkington one that zoomCat has pictured from Stoddard. The price was $599.00 but considering that shipping was free, I found it a good value as the Porsche Classic Parts replacement.

Intersting find!!!

The Pilkington glass is made in St Helens, England, XYG is made in Hong Kong, China.

That would explain the price difference. Quality - well that would require direct comparisons.

What I do find interesting is the Porsche branding. From what @wonkipop said, it only appears on Porsche certified parts. I don't think you can put that on without their blessing. To get approval for use of that mark, I would think that Porsche certified the glass to meet specifications for bend, form and size. I am certain Porsche still has the blueprints on file for that part. If Pilkington just cloned that mark not knowing what it was, well, thats a different story.

I think I mentioned earlier in the thread how companies make replacement glass that they were never OEM tooled for.
They go out and buy a piece of glass from someone. Ideally it is made by the OEM, but that is not always the case. From that piece of glass they make a mold to represent the shape and size and build the tooling from that. If that sample glass is out on size or bend, then so will anything they make. Glass can flex so we did make compensations for any twists or non symmetries that we found - if it looked like it was out a bit. Like I said a photocopy of a photocopy of a photo copy. There are few if any OEM w/s kicking around to make an accurate copy of these days for the 914.

When we were making replacement glass, accuracy was not that critical as it was made to a sample of god know what quality. Bob at the local auto glass could fiddle with it to make fit. OEM was more demanding since they would not tolerate stuff like that on the production line. Thats why they have tolerances to meet. Bob doesn't have those tolerances.

If that is a legit licensed use of the Porsche parts logo, it should be made to OEM data from Porsche - if I correctly understood the use of that logo. XYG will only have made theirs on the basis of a piece of glass they found.

I have a replacement w/s in the box from the Porsche dealer... I will need to check if I have that logo on mine...

@vitamin914
when i was digging around on this topic i found information that said pilkington took over the SIGLA brand. i think they purchased Flachglass gmbh who made SIGLA screens in a company takeover and then disbanded or divested themselves from it a little later but retained the copyright on the SIGLA branding. presumably they also kept all moulds, drawings etc.

basically that pilkington screen is a SIGLA screen more or less.'
why porsche still use them for the parts.

is it better than XYG. probably. is it worth 3 times as much. probably not?

if you own an early 911 and really want to get your wallet emptied pilkington do another trick. they will actually produce you a reproduction SIGLA brand screen, green glass and all. with period correct etching. though i think there is something about the E in a circle mark, it has to be there. so its not 100%

we were all just having fun with this thread but i did find the mercedes guys who restore pagodas and other such m b exotica from the 60s will pay a fortune to get hold of a correct vintage screen for one. i don't think the 914 world has gone that insane but i wouldn't be surprised with 914/6s if it went that way at some point. its all about how much the car is worth.

Just got my front screen, from my local Porsche dealer in Mexico City, yesterday.

Thanks PORSCHE, not an easy part to source here for my 914.



Click to view attachment
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Ive still got one of those boxes.

Probably of little value to this thread. I just checked my recently acquired 71 914/6 and the windshield has no marking at all. i have most of the service receipts so i can check to see if the glass replacement is noted on one of them. The receipts do confirm that it has 66,000 + original miles on it so there may be one about glass replacement. The car has been repainted once so that may be when the windshield was replaced.