windshield aluminum trim installation for roadster

[William Boyd]

after searching this topic I am still confused on how to install the trim that goes in the rubber groove of the windshield. Can I install it after the windshield is in place. If so how do I do it. this is a 356B roadster. I have already installed the windshield but can take it back out if necessary.

[Mike Wilson]

The aluminum trim is installed before the windshield is installed on the car. It may be possible after but I hear it is a pain.

Mike

[George Hussey]

it is a pain in general to install the roadster windshield and the trim. The contour of the cowl is such that if the replacement windshield varies slightly, the windshield will break trying to pull it in. With the new seals, a new windshield, and new trim, mated to maybe rechromed frame, and refinished cowl, you are dealing with three dissimilar parts that have never "lived" with each other so great finesse and patience has to be taken to get them all in harmony. Always best to completely assemble everything and pull it into place. Does not look like it is going to pull behind the two screw on cowl gutters but always does, eventually.
I am going to have to take mine apart soon to get one of the posts rechromed (after all of these years, a bit of it has flaked) and dread what I am going to have to do. However, I am NOT going to use any new materials!!!!

[Wes Bender]

The trim is always installed before rather than after.

[Doug McDonnell]

Where is Roy Smalley? He can answer honestly about this. viewtopic.php?f=1&t=41210&p=262182&hili ... ld#p262182 Everything I have read leads me to believe that this is a job for someone with experience. Some things are just above my pay grade.

[Randy Mittelstet]

Just passing on a tip I got from another member regarding new windshield install.
Only tighten the windshield post nuts no more than is absolutely necessary to help avoid cracking.
I did mine just a bit more than hand tightened. So far after several years no problems .... Now I've jinxed myself!

[Roy Smalley]

Nothing has changed still a PITA. It used to be easy to find the write up on the process. The subject is down the list here: viewtopic.php?f=1&t=36853 then use the key words to find the article. Hopefully in my dotage the three roadsters that are in the shop are the last I will have to watch installed since I have handed off the real work to Billy Fronterhouse that will soon have it all.

If you need some specific help contact me and I will give you a shout.

[Mike Wilson]

I remember years ago at the Pittsburgh Grand Prix meeting a fellow 356-er that I had been talking with on line. We went to check out his roadster which had a large crack that occurred as he was staging his car on the lawn of the golf course. Just the unevenness of the terrain twisted and cracked it.

Mike

[Ed Pimm]

This is from a Porsche Service Bulletin, it has served me well in the installation of many windshields.

[Dan Haden]

The following is something I wrote after spending a lot of time with Bruce Baker fitting new glass and rubber into the windshield of my Convertible D many years ago. I submitted this to a long ago thread, but based on the current conversation it may help some others wrestling with the same problems we had back then. In particular, I think I can say with some authority that the factory bulletin on base angle placement should be ignored because of the changes in base rubber configuration with the repro rubber. Bruce told the story of a customer who brought in her all original Conv D to have the windshield rubber replaced. While he was rehearsing in his mind how to tell her that based on his experience she might want to keep the checked and brittle original rubber rather than pay for what could be an expensive proposition, she was rummaging around in the trunk and came out with OEM rubber in sealed plastic, including the base rubber, the post base rubber and the frame channel rubber. She said she was in Germany recently and searched around until she found the original stuff in the basement of a dealership that had been selling Porsches since the mid 1950s. Bruce said that using that rubber the job took less than two hours, with no fiddling required.


New, expanded and improved version, done 11-12-03:

It took us about 3 weeks of 8 hours plus per week to get the windshield on right. I had bought a new Sigla glass, which we used. It fit the frame pretty well, requiring only a little straightening of the curves of the frame near the ends. We put it all together using cardboard shims and tape to hold the glass in the frame in the proper position and then used the factory bulletin recommendations for measurements to locate the metal angle strips on the cowl. (The metal angle strips usually have to be recontoured as well as relocated. Get out your metal shrinker and stretcher and get to work.) Then we tried to fit the base rubber and had to trim and doctor it to get it close to laying down properly. (This involves razoring off strips of the "bulb" that is the part of the base rubber that forms the channel for the bottom of the glass. It is too thick to allow the base rubber to sit down flat on the cowl.) We finally got it seeming right with only the right side near the vent not laying down well. We had moved the middle of the metal angle strips farther back to help things (we had moved the entire strips back more than a quarter inch from the factory position when we did the factory bulletin adjustments). In the almost right position we tried to install the 5 piece aluminum trim and found that putting it in held the rubber base down (except at the bad place near the right vent), but that in installing it we could not keep the rubber from pulling off the bottom of the glass. We took everything off again and reconsidered. We had been planning to not install the frame channel rubber in one piece, but rather to hold the glass in with shims and caulk and to glue the edge of the channel rubber on at the end. (This is a normal procedure because if the glass/frame fit is not very, very good the full rubber seal can cause the frame to put stress on the glass, and we all know what happens when there is stress on the glass. Clink.) Because the glass fit so well in the frame Bruce thought we should go ahead and try to use the channel rubber after grinding off the internal ribs. When we did that we could bring the glass down a bit further (because the rubber "lips" stick out beyond the edge of the frame the glass can be moved downward and the "lips" will still grab the glass. If you are gluing the "lips" on after the installation, you can't count on the "lips" to give enough mechanical grab to really hold the glass). Using small pieces of base rubber section and moving them around we found that we should probably move the angle strips forward an eighth to a quarter inch. (Do you notice that we are getting them back to near their original position? The factory bulletin method doesn't seem to work well for repro base rubber.) We did that (drilling out the pop rivets for about the 6th time), installed the base rubber and found that the angle of the glass as it fits the base rubber to be greatly improved. The purchase of the base rubber on the glass was better than before, but still tenuous. We used 3/16th inch aluminum shims at the rear of the post bases to pitch the whole frame more forward to lower the center edge of the glass. Installation of some foam weatherstripping under the base rubber in strategic spots also helped to solve the problem by pushing up the glass groove part of the base rubber. Getting the original 5 piece strip installed took some doing, as the contour of each of the components was slightly different. (This entails the 'string in the groove' process for those who haven't been through this. I got so I could regroove the string in less than 10 seconds after 20 or 30 tries. If they were still making these things, I could work on the assembly line.) One piece went in perfectly, but the other two finally went in with some spots where the rubber at the glass was a bit lower than perfect. (Putting the five piece strips in the rubber changes the way the rubber is shaped.) The original aluminum tabs that attach to the wiper tubes were much too short -- new repro ones are longer and have elongated holes. The new ones fit the bill with only a little jiggering. After all was in place the gasketing was siliconed into place, holes and gaps filled and smoothed with silicone and any base rubber lifting adhered down to the cowl.

I estimate that we put the windshield assembly on and off the car 30 or more times. Almost every time it had to be bolted down and the rubber post bases picked into proper position. In hindsight it is probably a miracle that the glass was not damaged in one of these operations. (Bruce and I got so we could install the frame with glass on the car with post base rubbers properly located in less than a minute, fully tightened down. All the rest of the time went into fitting, measuring, fiddling, trial and error, and banging our heads against the wall.)

Lessons learned: rather than doing a "dry" fitting of glass in frame with shims to set base metal angles it is better to get the glass with channel rubber put in place before checking base angle placement. (This assumes that the glass/frame fit is good enough to use this method. If it is not, the 'shim now and later glue in the channel rubber "lips" method' will have to be used.) Then using sections of base rubber (the same profile that you will use) the best placement (and curvature) of the metal angles can be determined. Use actual scrap pieces of base rubber to check for metal angle placement as the dimensions in the factory bulletin do not seem to work with the repro rubber. Only then should you drill and pop rivet the angles in place. If we had followed this procedure, we would have reduced the time spent by more than half. If the frame has been on the car before and no new part is added to the equation, it is likely that little or no movement of the angles will be needed. If the base rubber is new or glass is new, it will probably require moving the metal angles. Much of the work required is caused by the new glass having a slightly different contour than the original and a considerably shorter center section, leaving too much space between its lower edge and the cowl.


Added 12-4-03

I spent a lot of time trying to fit the side window rubber seals and the side window glass to give a proper seal. On the driver's side (I think) the window track in the door had to be adjusted all the way outboard plus some (with grinding) to even get close. The rubber seals had to be cantilevered and shimmed out somewhat to make a seal. The other side was better, but it was still near the limit of the channel adjustment.

After I was done I tried to figure out why things were so hard to adjust. Looking at the car from front and rear I noticed that the top frame was lopsided slightly. In other words it was bent so that it was pushed to one side and was not symmetrical. The top had been fitted to the frame so it looks fine, but the frame is not straight. Presumably if the frame is made straight, the windows will be able to be adjusted more easily and nearer the middle of their range rather than at the limits.

If/when the top is replaced, the frame should be straightened and the seals and windows readjusted to a more normal position. I suppose it is possible to straighten the frame before then, but I would worry that the top would not fit properly, which would probably be a bigger problem than the window sealing is now.

[Brad Ripley]

Great discussion above, especially Dan's above. You'll read a similar phrase a few times: "it might break" -- fortunately, Stoddard NLA has a good stock of Roadster windshields -- order two, you might need the second one! If not, hold on to it for the future.

[Dan Haden]

Brad's comment is appreciated, but it brings up a bad memory. I had ordered a roadster windshield from Stoddard back in the '80s sometime, knowing that I was going to need it when completing the restoration of my Conv D. There was a PPG windshield that came with the car and a used frame and posts from another car that I could use "loosely" installed on the car to keep the bugs out of my teeth over the 5 or 6 years between drivability and "all buttoned up." When I was ready to begin final windshield installation I pulled all of my new parts, rubber and glass out of basement storage. The posts had been rechromed but the channel frame was in pretty good shape. Everything was clean and ready to go. I pulled the new Sigla glass out of the foam-in-box in which it had been sent from Germany and forwarded to me from Stoddard. A first rough dry fit of parts showed that something was horribly wrong. All of my parts had been in use on the car for a number of years except the Sigla glass. Placing the new glass on the old PPG I saw that they were similar, but not exact in either dimension or configuration. You can imagine the ensuing conversation with Stoddard: "I just opened up this windshield box and found that it was the wrong glass even though the part no. on the box is correct." 'Oh, ok, give me the order number.' "XXXXXXX" 'That number doesn't show up in our system.' (New computerized system that had been fired up since my order some years before) The end of the story was that I bought a new Sigla windshield, 'at cost' and still have the mystery windshield in my basement. Over the years I have sent the engraved numbers etched on the glass (which, as near as I can tell, are meaningless and do not identify the glass in any way) to a number of auto glass experts who could not tell me how to identify the car it fits. I have lugged it to Roundtop, Hershey and Roundtop with a sign asking for any help in figuring out what car it fits, all without success.

So, if you do take Brad's advice and purchase one, two or more windshields, I recommend that you open all of them upon receipt and lay the glass on your current installed windshield to make sure it is the right one.

[Brad Ripley]

Dan, Did you receive glass marked SIGLA or marked Sudglas-Kristal ? The 'bug" you show is Sudglas.

[Dan Haden]

Brad =

I don't really remember. If I had to say, I would say it had neither or I would have included it in the image file that I sent around to experts. It is on a high shelf in the basement and with a recent shoulder surgery it will be a while before I can get it down. But I will check and report back.

[Dan Haden]

I just looked at the "bug" again. It says Sudglas-Kristall on the second line so you are right that it is not SIGLA. Good to know, but I don't think it gets me any closer to knowing what kind of car it goes to. In my dreams I hope for it to fit an Abarth Carrera or similar and is the only remaining spare from a very important run of glass. I imagine in reality that it belongs to some other roadster type car because the size and the corner shapes are very similar to a Conv D. A coupe normally has more rounded lower corners than a roadster with a removable frame.