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FastWoman
12-10-2007, 03:53 PM
Hi all,

I just installed one, and I thought I'd let you know how it went, in retrospect.

The guy who made mine is Peter Rothenbacer of Waxhaw, NC. His Ebay seller name is prothe. He claimed the plastic is a bit softer than BMW's and is more scratch resistant. To me, the plastic seems to have the same consistency, with perhaps a bit more optical clarity. I can't comment as to the scratch resistance yet. The construction of the window is a bit different. BMW has a molded rubber lip that the top's canvas inserts into. Mr. Rothenbacer's window has a canvas flap that is cemented down over the top's canvas. The BMW top is machine made, so the stitching is perfect. The aftermarket window is handmade and has occasional irregularities accordingly.

I had a bit of difficulty zipping the window into place, and I wish somebody (the seller?) had told me the following: The zipper slider the seller supplies is slightly oversized, presumably to ease the insertion of the zipper ends. Although it zips for the most part, there are occasionally skips whereby the zipper doesn't quite come together. Even when it appears to come together successfully, the teeth might not be seated correctly, so the zipper will easily separate. After about 3 zipping attempts, the last of which appeared successful, we went about sewing the ends to secure them. When we were finished sewing, one of the corners popped apart. :mad: The fourth time was the charm. That time, we inspected the zipper VERY CAREFULLY as we moved the slider along. Whenever there was questionable area, we backed up the slider and re-zipped. I eventually discovered the best way to tell if a section was successfully zipped was by feel. If the slider moved freely, it was a good zip. Wherever I felt resistance, there was trouble. Anyway, the fourth zip did it. We did a lot of poking and tugging to make CERTAIN the zipper wouldn't separate, before committing to sew the ends again!

Then came the cementing. The seller provides a little bottle of rubber cement to seal the window. I used about 2/3 of the bottle to run a bead around the inside of the window's canvas lip, and then I inserted the top's canvas into the bead. That presumably was enough to seal the window, but not enough to make the job look neat, as the window's canvas trim would not lie flat. (I didn't expect it to.) So I then pulled out some gel-formula contact cement and a small disposable brush (West System). I applied cement underneath the window's trim and on top of the top's canvas and then stuck the whole thing down.

The window looks pretty neat. There is one stitching irregularity in the upper right corner, creating a bit of a bag, but it's not bad. I also got the alignment just a tiny bit off, resulting in a very subtle diagonal wave across the window. I could have aligned the zipper better to eliminate this wave (which was not present in the first three zips), but I was so tired by that point that I just said, "@#$% it! It's close enough!" I think the wave will go away over time. Overall, the fit was a tiny bit looser than the old BMW top (which might have shrunk?). It turns out I had to tighten my top anyway (to fix a leak), so it all worked out fine in the end.

I did a leak test after the cement had cured 24 hr. It was tight as could be.

One benefit of the aftermarket top is the absence of the molded rubber lip, which had rubbed two grooves in the canvas overlying a frame piece when the top was folded down. The aftermarket top lies flatter, so the grooving problem should be remedied now.

In hindsight, there are pros and cons to either the BMW window or the aftermarket window. I don't think either solution is clearly better than the other.

Peace,
Sarah

cngizbleevng
12-10-2007, 08:07 PM
I know what you mean when you say the rubber surround wore a couple areas on the canvas. That happened to me too. I notice that using the window blanket covers and protects that area, as well as the window, so I use the blanket every time now.

Any pics you can post of the final appearance? What was the cost?

The Other Tom
12-11-2007, 04:00 AM
Thanks for the write up.

FastWoman
12-11-2007, 10:02 AM
I can't get to it today, but I'll try to post some pictures later. :)

Cost was $85 + $13 S&H.

Regarding the grooves, you might dab a bit of clear fingernail polish into the worn areas to seal the fibers and bind them together. That will also harden the area to slow down the wear.

Peace,
Sarah

cngizbleevng
12-11-2007, 11:12 AM
Regarding the grooves, you might dab a bit of clear fingernail polish into the worn areas to seal the fibers and bind them together. That will also harden the area to slow down the wear.

Peace,
Sarah

I'd be a little concerned about doing that. If that area is meant to be flexible (and hence a possible reason for fraying there), applying a nail polish might result in cracking of the canvas when the polish breaks up. The polish breaking up could also yield sharp shards that could damage the canvas further. Just a thought.

FastWoman
12-11-2007, 11:56 AM
Hmmm... Good point!

FastWoman
12-21-2007, 06:24 PM
As promised, here are a few snapshots of the new window:

http://www.graphic-fusion.com/miscpics/z3window4.jpg

The slight diagonal wave I initially reported has gone away. The window appears nice and tight:
http://www.graphic-fusion.com/miscpics/z3window3.jpg

Here are two pics of the canvas trim (as compared to BMW's molded rubber trim).
http://www.graphic-fusion.com/miscpics/z3window1.jpg

http://www.graphic-fusion.com/miscpics/z3window2.jpg

The only flaws in this hand-made window are in two of the corners. This is the worse of the two corners, showing just a tiny bit of bagging. (You can see the dimple by the reflection.) I don't think it's that serious a problem, though.
http://www.graphic-fusion.com/miscpics/z3window5.jpg

All in all, I rather like this window. As I said, it eliminates the problem of the BMW rubber molding rubbing a groove in the hardtop canvas! :)

Peace,
Sarah