Carbon Fiber (CF) Z4 Coupe roofs-Feeler participants

[Twisted Six]

Originally Posted by 3point0

we just started using some special marine sealant at work for sealing acrylic to aluminum under 14ft of water (I work in a fluid dynamics lab and we make models of stuff) anyhoo it's been really good at keeping water out, replacing fasteners and being relatively easy to remove. Made by Sika and readily available. I can dig up the exact name if you're interested.

Thanks, and YES. I'm always interested in materials to study for this type of venture.
Oddly enough, what BMW used on our roofs seems exactly like what I've used for windshield mounting. When heated with a heat-gun it becomes semi-liquid and malleable.Yet when under 120* it remains firm.

[Twisted Six]

Pix of my coupe with roof removed for testing of structural integrity etc.

[3point0]

Originally Posted by Twisted Six

Thanks, and YES. I'm always interested in materials to study for this type of venture.

PM sent

[RobMCoupe]

Love to see the fittings especially from the inside.

[Twisted Six]

Originally Posted by RobMCoupe

Love to see the fittings especially from the inside.

I'm not sure what your referring to oter than the bolts which held it on ?

[RobMCoupe]

Yes. How is the roof mounted and hardware.

[Twisted Six]

Originally Posted by RobMCoupe

Yes. How is the roof mounted and hardware.

Thats been covered in previous comments here, but once more.......there are four 10mm bolts. One in each corner that go through a metal tab or ear on the cars inner roof frame. The bolts go into the roof panel itself. There was a black urethane flexible sealant going around the perimeter.

While I doubt most will drive around with the roof removed as I have the last few weeks....it sure has been nice. To do that long term or often I'd need to devise/engineer the same type of speed air screen as used when sunroofs open up. This is to uplift the air going over the roof and keep it from dropping into the cabin making disturbance and buffeting.

I'm thinking the Clear Moonroof I'm making will suffice those wanting the open top view.-( Other thread).

[Twisted Six]

I'd like to poll the current members who are on the below posted list.

The question is >

" If the roof is removable, do you plan on driving with it off and if yes, how often yearly would you estimate ?"

If you are not on the list but own a coupe and have considered this option, feel free to comment as to how you would utilize this option.

I'm doing this to ascertain the baseline choice of seal/gasket material that I will use for both the Moon-roof-(clear) and Carbon Fiber roofs. The seal is of a custom shape and can be costly. In a niche lot of cars like ours-(low numbers), I won't be making two versions of seals.

Vote on !!

This list of buyers last updated 1-24-13.

1)-Dark Schnitzer---------2x2 Twill-V-weave.-Would remove often.
2)-inTgr8r----------------2x2 Twill-standard-weave
3)-VinnieAces------------ 2x2 Twill-V-weave (Maybe)
4)-cfine88----------------2x2 Twill -standard weave
5)-Finnegan--------------2x2 Twill - standard weave ?
6)-NEKO ---------------- 2x2 Twill-V-Weave
7)-mexicobmw------------1x1 Plain weave
8)-habitat412-------------1x1 Plain weave
9)-doktore----------------2x2 Twill V.
10)-RobMCoupe-----------2x2 Twill
11)- Jumbosock-----------2x2 Twill-standard-weave
12)-GCDC-----------------2x2 Twill - standard weave
13)-Urluz3n---------------2x2 Twill- standard weave
14-2point0---------------2x2 Twill-V-weave

[inTgr8r]

Remove never

I'm leaning towards permanent OE installation.

[Twisted Six]

Originally Posted by inTgr8r

Remove never

I'm leaning towards permanent OE installation.

Originally Posted by Twisted Six

I'd like to poll the current members who are on the below posted list.

The question is >

" If the roof is removable, do you plan on driving with it off and if yes, how often yearly would you estimate ?"

If you are not on the list but own a coupe and have considered this option, feel free to comment as to how you would utilize this option.

I'm doing this to ascertain the baseline choice of seal/gasket material that I will use for both the Moon-roof-(clear) and Carbon Fiber roofs. The seal is of a custom shape and can be costly. In a niche lot of cars like ours-(low numbers), I won't be making two versions of seals.

Vote on !!

This list of buyers last updated 1-24-13.

1)-Dark Schnitzer---------2x2 Twill-V-weave.-Would remove often.
2)-inTgr8r----------------2x2 Twill-standard-weave-Remove never
3)-VinnieAces------------ 2x2 Twill-V-weave (Maybe)
4)-cfine88----------------2x2 Twill -standard weave
5)-Finnegan--------------2x2 Twill - standard weave ?
6)-NEKO ---------------- 2x2 Twill-V-Weave
7)-mexicobmw------------1x1 Plain weave
8)-habitat412-------------1x1 Plain weave
9)-doktore----------------2x2 Twill V.
10)-RobMCoupe-----------2x2 Twill
11)- Jumbosock-----------2x2 Twill-standard-weave
12)-GCDC-----------------2x2 Twill - standard weave
13)-Urluz3n---------------2x2 Twill- standard weave
14-2point0---------------2x2 Twill-V-weave

Very good start, thanks !

[3point0]

Originally Posted by Twisted Six

I won't be making two versions of seals.

for non-removable you could use the RTV style sealants (like the one I sent you info on) or maybe something like an extrusion for them both

seals

You're really making want a coupe just for the clear roof, really missing the partial-open feel of a glass sunroof. Maybe I should just add one to my roadster, lol

[philjw]

I'm not sure if I'm prepared to make such a drastic modification to my car, but the idea of a removable CF roof is damn sexy...

[Incompatible]

Speaking of the OEM, CF, and Moon-roof options, any significant weight difference between the three? A roof mod was not really on my radar, but that might change.

[Finnegan]

No plans to remove.

[Twisted Six]

Originally Posted by 3point0

for non-removable you could use the RTV style sealants (like the one I sent you info on) or maybe something like an extrusion for them both

seals

You're really making me want a coupe just for the clear roof, really missing the partial-open feel of a glass sunroof. Maybe I should just add one to my roadster, lol

The OEM sealant is identical to windshield urethane. Probably similar to what your link is. I thank you for that too !
And yes...the clear roofs will be nice. Feels so open with out having to do anything.

Originally Posted by philjw

I'm not sure if I'm prepared to make such a drastic modification to my car, but the idea of a removable CF roof is damn sexy...

I couldn't believe how much difference it made in the overall cabin size and brightness. I think you'll be more convinced once you see pictures of it in place !

Originally Posted by Incompatible

Speaking of the OEM, CF, and Moon-roof options, any significant weight difference between the three? A roof mod was not really on my radar, but that might change.

From what I can tell thus far Lance, the CF roof will be MUCH stronger than the alloy OEM, less likely to be damaged-(as in in you can't dent it, but you can stand on it !) and will weigh slightly less depending on how I lay it up.

If I laminate to have the same flexibility as the OEM panel skin, the final weight would be about 2/3's less.If I make mine more robust...about 1/2 less.

I don't think the Clear Acrylic roof will weigh in much less than the OEM since it is made from an optic quality material bonded to my CF substructure and silk screed black (like a factory glass is). Its more of a luxury item anyway.

Track day...run the CF. Going for a cruise with mama.....Clear roof ! That would be using my removable roof seal though. Once you use the semi-liquid Polyurethanes ...its glued again.


1)-Dark Schnitzer---------2x2 Twill-V-weave.-Would remove often.
2)-inTgr8r----------------2x2 Twill-standard-weave-Remove never
3)-VinnieAces------------ 2x2 Twill-V-weave (Maybe)
4)-cfine88----------------2x2 Twill -standard weave
5)-Finnegan--------------2x2 Twill - standard weave ?-No plans to remove.
6)-NEKO ---------------- 2x2 Twill-V-Weave
7)-mexicobmw------------1x1 Plain weave
8)-habitat412-------------1x1 Plain weave
9)-doktore----------------2x2 Twill V.
10)-RobMCoupe-----------2x2 Twill
11)- Jumbosock-----------2x2 Twill-standard-weave
12)-GCDC-----------------2x2 Twill - standard weave
13)-Urluz3n---------------2x2 Twill- standard weave
14-2point0---------------2x2 Twill-V-weave

Bare in mind guys and gals, the roof on our cars is not a structural panel that MUST be glued to strengthen the car as I've found. I've driven it now with the four bolts loose as well as tight. There was no movement or rattling or anything. I took it up and down and across some ridiculous transitions, some that raise one tire off the ground in testing.

The bonus to having a removable seal of high quality is for ease of panel replacement if you ever need to re-install the factory roof.....selling etc.

This seal will be airtight,watertight and under compression somewhat tacked in place.

[RobMCoupe]

No plan to remove. Like the CF look too much to take it off.

[Twisted Six]

Originally Posted by Twisted Six

The OEM sealant is identical to windshield urethane. Probably similar to what your link is. I thank you for that too !
And yes...the clear roofs will be nice. Feels so open with out having to do anything.



I couldn't believe how much difference it made in the overall cabin size and brightness. I think you'll be more convinced once you see pictures of it in place !



From what I can tell thus far Lance, the CF roof will be MUCH stronger than the alloy OEM, less likely to be damaged-(as in in you can't dent it, but you can stand on it !) and will weigh slightly less depending on how I lay it up.

If I laminate to have the same flexibility as the OEM panel skin, the final weight would be about 2/3's less.If I make mine more robust...about 1/2 less.

I don't think the Clear Acrylic roof will weigh in much less than the OEM since it is made from an optic quality material bonded to my CF substructure and silk screed black (like a factory glass is). Its more of a luxury item anyway.

Track day...run the CF. Going for a cruise with mama.....Clear roof ! That would be using my removable roof seal though. Once you use the semi-liquid Polyurethanes ...its glued again.



Bare in mind guys and gals, the roof on our cars is not a structural panel that MUST be glued to strengthen the car as I've found. I've driven it now with the four bolts loose as well as tight. There was no movement or rattling or anything. I took it up and down and across some ridiculous transitions, some that raise one tire off the ground in testing.

The bonus to having a removable seal of high quality is for ease of panel replacement if you ever need to re-install the factory roof.....selling etc.

This seal will be airtight,watertight and under compression somewhat tacked in place.

1)-Dark Schnitzer---------2x2 Twill-V-weave.-Would remove often.
2)-inTgr8r----------------2x2 Twill-standard-weave-Remove never
3)-VinnieAces------------ 2x2 Twill-V-weave (Maybe)
4)-cfine88----------------2x2 Twill -standard weave
5)-Finnegan--------------2x2 Twill - standard weave ?-No plans to remove.
6)-NEKO ---------------- 2x2 Twill-V-Weave
7)-mexicobmw------------1x1 Plain weave
8)-habitat412-------------1x1 Plain weave
9)-doktore----------------2x2 Twill V.
10)-RobMCoupe-----------2x2 Twill-No plan to remove.
11)- Jumbosock-----------2x2 Twill-standard-weave
12)-GCDC-----------------2x2 Twill - standard weave
13)-Urluz3n---------------2x2 Twill- standard weave
14-2point0---------------2x2 Twill-V-weave

[GP20]

If the CF actually gets built, I'll buy one, and never remove it till I sell the car someday.

I'm sure many will disagree with me, but I think this is being made more complicated than it really needs to, with the mounting railings and all. How many of us will actually buy "both" a CF roof and a moon-roof to justify having the special mounting railings? From what TCK and BMS used to talk about, the hardest part was getting the weaves to actually look flawless; the easiest part was figuring out how the CF roof mounted to the car. For every 2~3 flawless CF roof they built, they had to scrap one because the weaves came out not looking right.

Don't get me wrong, I applaud and respect your efforts to build these CF roofs - no one else even bothers to do it anymore, and I'll put money down when the CF roofs do get built. But this project has been going on for how long? A year and a half? 2 years? How many CF roofs will you have to sell and how much will they cost in order to justify the shop rents and toolings and labors and everything that you've been paying for?

I apologize if I'm coming off as critical (and I know I am). I've been following this development thread for a long time. I WANT to buy your CF roof. But after a year and a half, all we're seeing in this thread are photos of a topless coupe (anyone with a knife and some tools can get this far in one afternoon) and the mentions of some grand ideas. At the rate this project is going, the pessimistic part of me says it'll never materlize. I'd love to be proven wrong (just while I still own my Z4MC).

[inTgr8r]

I appreciate dedication and high end design going into this,

but It's a thought..... If the seal is going to take a lot of R & D time.
Run some roofs to get things rolling & some cash flow.
I know I'd buy one right now and bond it OE style.

[Twisted Six]

Originally Posted by GP20

If the CF actually gets built, I'll buy one, and never remove it till I sell the car someday.

I'm sure many will disagree with me, but I think this is being made more complicated than it really needs to, with the mounting railings and all. How many of us will actually buy "both" a CF roof and a moon-roof to justify having the special mounting railings? From what TCK and BMS used to talk about, the hardest part was getting the weaves to actually look flawless; the easiest part was figuring out how the CF roof mounted to the car. For every 2~3 flawless CF roof they built, they had to scrap one because the weaves came out not looking right.

Don't get me wrong, I applaud and respect your efforts to build these CF roofs - no one else even bothers to do it anymore, and I'll put money down when the CF roofs do get built. But this project has been going on for how long? A year and a half? 2 years? How many CF roofs will you have to sell and how much will they cost in order to justify the shop rents and toolings and labors and everything that you've been paying for?

I apologize if I'm coming off as critical (and I know I am). I've been following this development thread for a long time. I WANT to buy your CF roof. But after a year and a half, all we're seeing in this thread are photos of a topless coupe (anyone with a knife and some tools can get this far in one afternoon) and the mentions of some grand ideas. At the rate this project is going, the pessimistic part of me says it'll never materlize. I'd love to be proven wrong (just while I still own my Z4MC).

I thank you for the comments. I think we've all thought these same sentiments as this has unfolded.

Originally Posted by inTgr8r

I appreciate dedication and high end design going into this,

but It's a thought..... If the seal is going to take a lot of R & D time.
Run some roofs to get things rolling & some cash flow.
I know I'd buy one right now and bond it OE style.

The seal wont take me THAT long to develop.That said, I wasn't going to let it interfere with the CF roof process since I had a feeling many of you might want to re-bond them as OEM and be done with it. As each roof set is post curing in the oven, I'll be doing other things.

The Urethane kits or proper caulk do have a short shelf time.....so that is something we can discuss later as I am closer to shipping.

Todays update : Pulled the plug out from the B-side mold and began the wet sanding prep (prior to final polishing).

After polishing comes semi-permanant mold release applied to prep for dry CF lay-up and vacuum bagging of the first set of panels.

About six more grits of sanding papers and I'll be polishing. If you look at the substructure closely...you'll notice the panels which will hold the optional honeycomb panels. These serve two purposes.
ONE: Sound reduction from out of doors(whether with or without incerts) and TWO:-roll-over safety as well as rigidity increases.

This was tough to pull off given our headliner design and construction.

If Kevlar is optioned.....a roll-over on track day( God forbid-or your choice of powers)..there will be a much lower chance if any of foreign debris puncturing your roof and entering your cabin !

If you hit or stand on your current roof it will dent and be damaged. This CF roof will do neither. Nor will hail mess with it.

[inTgr8r]

Freakin amazing!!!

[Finnegan]

Cool!