MYBAD79
Moderator
Not that you need any encouragement..... But hell, this is going to look cool 
My '76 restoration (long post)
- Thread starter denpo
- Start date
denpo
Carburated Nihilist
Not that you need any encouragement..... But hell, this is going to look cool
The proportions feel so right to me... the more I look at it, the more I like it.
I'm gonna sound like a weirdo, but there is a car I felt in love with at first sight : the Lancia Beta.
That's when I had the rear window cut that it all make sense. I loved the shape of the Lancia because of the proportion and angle of the back window. Now I have the same on the Vette.
FYI, the base of the back window have been moved backward exactly 1 foot.
MYBAD79
Moderator
Do you think that Lancia rear window glass has about the correct dimensions? A quick search showed the surrounding gasket and window louvers are still available on Ebay.....
Would be cool if you could find a Lancia rear glass incl the defroster.....
Would be cool if you could find a Lancia rear glass incl the defroster.....
denpo
Carburated Nihilist
I strongly doubt they would match, the curve on the top corner isn't curvy enough.
That's too bad because the louver is pretty rad.
For the glass, the price for custom shape 3mm tempered glass is not bad at all, and for the defrost, there's aftermarket kit. I will put one.
MYBAD79
Moderator
Still would be nice to have something that has some "factory" dimensions but that Lancia is probably way to rare anyways...
If you ever need a new piece of glass it would be cool to have something that is available but then again, rear glass never really breaks.....
Is that C3 hardtop a rear glass window or poly (plastic) ???
If you ever need a new piece of glass it would be cool to have something that is available but then again, rear glass never really breaks.....
Is that C3 hardtop a rear glass window or poly (plastic) ???
denpo
Carburated Nihilist
Well, last time I check with the glass shop, the glass was under 100$. Why bother?
I'll just keep the shape pattern.
Dunno about hardtop, never seen one IRL.
denpo
Carburated Nihilist
I've spent the week fitting my body to my mdf window.
Added another bungie rope to the setup.
With the number of turn around the wood beam it can tune the tension.
The tension that keep the mdf board against the body is actually very small, the board almost floats.
This way I ensure the board is not deformed in any way.
My main fitting concern was the top, I wanted a close shave and a symmetric line.
I added a couple of tack gluing. Once cured I'll start casting the channel from behind.
As you probably noticed, the edges of the board have been wrapped, with small hole cut out for the tacks.
Added another bungie rope to the setup.
With the number of turn around the wood beam it can tune the tension.
The tension that keep the mdf board against the body is actually very small, the board almost floats.
This way I ensure the board is not deformed in any way.
My main fitting concern was the top, I wanted a close shave and a symmetric line.
I added a couple of tack gluing. Once cured I'll start casting the channel from behind.
As you probably noticed, the edges of the board have been wrapped, with small hole cut out for the tacks.
denpo
Carburated Nihilist
Pretty much done with the upper half of the window.
I did it first because it's the hardest part, little if no access.
With the guide board tacked, I first 'molded' a couple of reference area, where I had a little bit of access, of a convenient hole to inject the filler.
Once cured I detached the board, fill the remaining areas, and press back the board to conform it to the plan.
The filler is a mix of epoxy and crushed fiberglass.
The lower part, which is much more accessible will get a true fiberglass treatment.
I did it first because it's the hardest part, little if no access.
With the guide board tacked, I first 'molded' a couple of reference area, where I had a little bit of access, of a convenient hole to inject the filler.
Once cured I detached the board, fill the remaining areas, and press back the board to conform it to the plan.
The filler is a mix of epoxy and crushed fiberglass.
The lower part, which is much more accessible will get a true fiberglass treatment.
MYBAD79
Moderator
That is some impressive work, keep the updates and pics coming 
denpo
Carburated Nihilist
During the week I've been able to mold the center of the bottom of the window frame.
It looks twisted because the bottom is not cut straight yet.
It's perfectly in the plane as it cured against the installed guide board.
I used a long styrofoam wedge shape to force fiberglass to stick at the top and on the reference board.
You can see the wrinkles of the plastic wrap.
In the pic the wedge have already been scratched out.
I will wipe it with acetone and fill the space with something.
A pleasant surprise is to see the curvature of the bottom slowly appear.
Once the wedge is completed and filled, I'll grind off this bottom edge, and will rebuild it with a lot of fiberglass. For not it's mostly resin an would crack supporting the window. I keep it for now as it hold the whole shape.
This is the kind of wedge shape I used.
Cut by hand with a razor blade at approximately the right angle (27°).
We are in the land of the cut twice measure never.
See
Told ya
This is the smae setup I used for the central part, two more layer come on top of this before I stick it to the frame from under.
Like that.
It's going really well, much better than I anticipated.
It looks twisted because the bottom is not cut straight yet.
It's perfectly in the plane as it cured against the installed guide board.
I used a long styrofoam wedge shape to force fiberglass to stick at the top and on the reference board.
You can see the wrinkles of the plastic wrap.
In the pic the wedge have already been scratched out.
I will wipe it with acetone and fill the space with something.
A pleasant surprise is to see the curvature of the bottom slowly appear.
Once the wedge is completed and filled, I'll grind off this bottom edge, and will rebuild it with a lot of fiberglass. For not it's mostly resin an would crack supporting the window. I keep it for now as it hold the whole shape.
This is the kind of wedge shape I used.
Cut by hand with a razor blade at approximately the right angle (27°).
We are in the land of the cut twice measure never.
See
Told ya
This is the smae setup I used for the central part, two more layer come on top of this before I stick it to the frame from under.
Like that.
It's going really well, much better than I anticipated.
JPhil
Huh?
Denis,
Looking at your rear window mod, which I really like by the way, a thought came to mind. Are you going to do anything for cabin vents back there?
I don't know if your car had "AstroVent" grills behind the rear window like mine, but even if it didn't I highly recommend doing something, probably in the buttress just behind the side window, like some of the Baldwin Motion cars or the old Ford Shelby Mustangs, or the early C2. It makes a great difference in cabin comfort.
Non-A/C cars had a vacuum operated flapper I believe, probably connected to the heater controls. My car, having A/C (when it left the factory), had permanent mounted plates covering the openings. I removed the plates and made a flapper I can open & close from the seat. I leave it open year round--full open in the summer it draws noticeable airflow through the cabin with the heater control on 'vent' and the windows closed. In the winter I leave it partially open and it helps draw warm air in through the heater.
Gills in the buttress would look cool too......
Looking at your rear window mod, which I really like by the way, a thought came to mind. Are you going to do anything for cabin vents back there?
I don't know if your car had "AstroVent" grills behind the rear window like mine, but even if it didn't I highly recommend doing something, probably in the buttress just behind the side window, like some of the Baldwin Motion cars or the old Ford Shelby Mustangs, or the early C2. It makes a great difference in cabin comfort.
Non-A/C cars had a vacuum operated flapper I believe, probably connected to the heater controls. My car, having A/C (when it left the factory), had permanent mounted plates covering the openings. I removed the plates and made a flapper I can open & close from the seat. I leave it open year round--full open in the summer it draws noticeable airflow through the cabin with the heater control on 'vent' and the windows closed. In the winter I leave it partially open and it helps draw warm air in through the heater.
Gills in the buttress would look cool too......
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denpo
Carburated Nihilist
Ok, at the exception of this little gap which is closed by now, the frame contour have been bridged.
And while I was at it, I redid the upper window edge, which is made of sealant, just like the fender seams.
Driver side is done, passenger side is gutted and waiting to be glassed.
And this is how I fight the gravity in this particular case.
I'm already busy building some meat behind those molded edges.
Next week I'll probably get the final contour shape and get the glass cut.
Then I'll build the other side of the frame to secure the glass in place.
And while I was at it, I redid the upper window edge, which is made of sealant, just like the fender seams.
Driver side is done, passenger side is gutted and waiting to be glassed.
And this is how I fight the gravity in this particular case.
I'm already busy building some meat behind those molded edges.
Next week I'll probably get the final contour shape and get the glass cut.
Then I'll build the other side of the frame to secure the glass in place.
denpo
Carburated Nihilist
First, glad you like the mod.
No, my '76 didn't have Astrovent, electric defroster instead.
Now I have conflicting thoughts about those setups.
On the Astrovent, as you describe, it's the back pressure behind the window, between the buttresses that suck air out of the cabin.
In the motion and the Shelby, they are outside and seems to rather draw air in.
Because my wildest mod so far is turning out rather fine I'm getting very cautious, like when you go to the casino for the first time and win straight away, beginner's luck, you tell yourself it's time to get out now.
I'm trying not to cross the blurry line that separate 'being creative' from 'Corvette Summer'.
So for now, no extra gills on the back, but I keep the idea of extra ventilation in mind , with a bigger window that would indeed be a inconvenience.
denpo
Carburated Nihilist
The base for the frame of the window is now complete. Done also it the filling of the top arch seal.
Now time to think about create the channel that will support the window.
Here's the seal I bought for the task :
Now time to think about create the channel that will support the window.
Here's the seal I bought for the task :
GoVetteGo
Well-known member
Denis - that is some very impressive work you are doing on the rear window mod. I am only 5' 10" and I can't imagine doing what you are doing!!!
Keep up the great work - very inspiring!!
John
Keep up the great work - very inspiring!!
John
7t9l82
Well-known member
almost identical to what Joel Rosen did with the Motion corvettes back in the day. made the interior way more useful , less like an El Camino inside.
denpo
Carburated Nihilist
Thanks you guys for the kind and encouraging words.
Probably both, I'm 6'6" and while it's convenient when you have to bent over to sand from outside (my back beg to disagree), I feel pretty shitty sanding from inside, laying on uneven surface (my back is full or hieroglyphs), with the arms barely extended and in awkward positions. Best workout evar!!!!
While the motion is a blatant, unashamed hatchback (edit: maybe fastback?) conversion, I rather see mine as a stealth space grab.
While shopping for my Vette is was pretty clear to me I didn't want a later years bubble back one, so I tried not to recreate it.
John, not sure you related to the height as a advantage or a disadvantage.
Probably both, I'm 6'6" and while it's convenient when you have to bent over to sand from outside (my back beg to disagree), I feel pretty shitty sanding from inside, laying on uneven surface (my back is full or hieroglyphs), with the arms barely extended and in awkward positions. Best workout evar!!!!
While I respect the Motion design, I'm rather after the hardtop look in term of window slope.
While the motion is a blatant, unashamed hatchback (edit: maybe fastback?) conversion, I rather see mine as a stealth space grab.
While shopping for my Vette is was pretty clear to me I didn't want a later years bubble back one, so I tried not to recreate it.
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denpo
Carburated Nihilist
Hey, good point you got here.
Anyone got pics of what the inside of 'trunk' of the Motion Phase III looked like?
denpo
Carburated Nihilist
Nevermind...
Look like he closed the sides and made speaker boxes out of it. I'll keep that in mind.
7t9l82
Well-known member
Motion did a couple of types, they did one like you are doing then they had the other style, which i never liked.
