Helion 911 sunroof panel development

[toddc]

Hello fellow Pelicans,

Following are a few pics of the process of creating a sunroof delete panel for the 911.

After much time and much interest in creating a sunroof panel that could be bonded into the roof for those wishing to remove the sunroof mechanism without actually having to replace the steel roof with one of our carbon skins, we have started the process of tooling a replacement sunroof panel that can be bonded into the existing roof structure after removal of the stock sunroof mechanism.

The pics below are of the model panel flanged and prepped for molding and then of the first surface coat applied. More pics to follow as development continues.

Thanks again,

ToddC
ps, one of our fine Pelican friends kindly donated the panel for this purpose a while ago and I've lost the contact info. You know who you are, please reach out.

thanks,

[riverstonefly]

Yes!

Sent from my XT1650 using Tapatalk

[juanbenae]

great idea! I would imagine leaving the sunroof pocket false ceiling in place it would help with maintaining rigidity. I cut all the false lid out and did a cheapo fiberglass insert during a racecar build. problem was the mold for the insert was done from a sunroof panel and there was gaping space where the felt seal should have gone. I'm no body man to be sure, but I could never get the bondo edges to not crack at some point due to body flex at the panel perimeter.. it was mechanically mounted as well let the record reflect.

I never had this issue, but taller driver's like having the false ceiling removed for the 1.5" head room it frees up, and the 5lbs or so of sheet metal

[hawaiipcar]

Cool

[Elombard]

Originally Posted by juanbenae

great idea! I would imagine leaving the sunroof pocket false ceiling in place it would help with maintaining rigidity. I cut all the false lid out and did a cheapo fiberglass insert during a racecar build. problem was the mold for the insert was done from a sunroof panel and there was gaping space where the felt seal should have gone. I'm no body man to be sure, but I could never get the bondo edges to not crack at some point due to body flex at the panel perimeter.. it was mechanically mounted as well let the record reflect.

I never had this issue, but taller driver's like having the false ceiling removed for the 1.5" head room it frees up, and the 5lbs or so of sheet metal

Then you keep a lot of the weight...which is the whole point?

[175K911]

Dang, where was this before I cut my full roof off to get rid of the sunroof mechanism and weight!!

[75 911s]

Could someone give me the pros and cons on this neat panel vs the fennlane metal panel?

From my understanding, both would remove the entire sunroof and supporting structure and then be bonded with glue. From what I can tell, Helion's would bond from underneath and the Fennlane panel bonds on the top.

In a rollover would the removed structure be much different from say a factory no sunroof coupe as far as rigidity? (Would I need a half cage?)

Thanks in advance!

[toddc]

Below are a couple more pics, tooling is now completed with the exception of cleanup and a couple of spots "off-part" that need correction before we go to production.

I'll try to answer a couple of the questions and comments that came before I made this post in multiple replies.

[toddc]

Originally Posted by 175K911

Dang, where was this before I cut my full roof off to get rid of the sunroof mechanism and weight!!

good question,

after 100+ roof skins made to date, the idea of making a sunroof only panel has come about over the course of a year for those who are not interested in cutting/fitting an entire roof skin.

[toddc]

Originally Posted by juanbenae

great idea! I would imagine leaving the sunroof pocket false ceiling in place it would help with maintaining rigidity. I cut all the false lid out and did a cheapo fiberglass insert during a racecar build. problem was the mold for the insert was done from a sunroof panel and there was gaping space where the felt seal should have gone. I'm no body man to be sure, but I could never get the bondo edges to not crack at some point due to body flex at the panel perimeter.. it was mechanically mounted as well let the record reflect.

I never had this issue, but taller driver's like having the false ceiling removed for the 1.5" head room it frees up, and the 5lbs or so of sheet metal

Good observation on the bondo and an under-estimated weight figure... the actual OE sunroof panel itself, all other things excluded weighs nearly 10 lbs. We anticipate a carbon part coming in under 1lb.
That said, body man or no, couple of things to keep in mind. Composites move at different temps and different rates than steel.

Proper way to bond the panel to the structure and fill the top-side gap is to use a urethane based adhesive like 3M or SEM composites panel adhesive to allow expansion and contraction, then surface and paint over if desired. This allows the parts to move as they may without affecting each other or the overall surface.
Bondo for a filler is too rigid for dis-similar materials and even worse for an adhesive. Yes, if you are filling a gap, whatever you put in that gap becomes an adhesive and needs to be thought of that way. Bondo (insert generic body filler name here) should be used only as a top coat over whatever repair/modification work has been done in order to surface for prime and paint.

Hope this helps,

[toddc]

Originally Posted by 75 911s

Could someone give me the pros and cons on this neat panel vs the fennlane metal panel?

From my understanding, both would remove the entire sunroof and supporting structure and then be bonded with glue. From what I can tell, Helion's would bond from underneath and the Fennlane panel bonds on the top.

In a rollover would the removed structure be much different from say a factory no sunroof coupe as far as rigidity? (Would I need a half cage?)

Thanks in advance!

Duane,

good comment,

couple of comments of my own, I'm not familiar with the Fennlane product or how it is installed.

Regardless of who makes the replacement panel and whether it is installed from the top or bottom, it will not be the same as OE.

That said and more to your point "would I need a half cage"? that's a question only you can answer.

On our end, we have provided many roofs for people who were converting sunroof car to track cars and needed a good way to eliminate as much weight as possible and gain access to welding in the top of the cage. For these customers, it's a perfect solution.

The tool we've just created is for the panel itself for those who want to get rid of the metal sunroof for whatever reason, either with or without the supporting structure but don't have the stomach or budget for cutting off the entire steel roof and replacing with one of our full roof skins....


I hope this helps,

TC

[juanbenae]

todd, does this panel require the false ceiling that houses the sunroof to be removed? maybe I misunderstood and it does come out? seems with the flanges on the unit shown you could tuck them up to the actual roof panel with the false lid still in? do you epoxy the flanges to the inner roof surface? has your mold for the panel tightened up the felt seal gap I noted above?

Originally Posted by Elombard

Then you keep a lot of the weight...which is the whole point?

well, right. it's actually the sunroof panel, motor, rails & other associated SR junk that generates most of the weight. maybe 5-6 pounds of sheet metal in the false roof structure. here's all what was cut out of mine when I took the plunge..




so, here's what I did for my current 911 sunroof issues.... found a 75S California smog exempt factory SR & power window delete car. light as they got late!

[billwagnon]

If anybody's deleting a longhood sunroof, I need the left piece of the wind deflector because my little hinges broke.

[toddc]

[QUOTE=juanbenae;9584748]todd, does this panel require the false ceiling that houses the sunroof to be removed? maybe I misunderstood and it does come out? seems with the flanges on the unit shown you could tuck them up to the actual roof panel with the false lid still in? do you epoxy the flanges to the inner roof surface? has your mold for the panel tightened up the felt seal gap I noted above?




thanks for the reply,

Let's be really clear, the part we are making is a carbon clone of the outer surface of the stock sunroof panel that will need to be bonded into the vehicle. There have been no adjustments to outer dimensions made to compensate for seals, etc. It is a clone of the steel part.
The resulting gap created by eliminating the seal will need to be filled post installation by the end user.
How the interior is trimmed, fitted, etc., will be up to the consumer.

The flanges you saw on the tool allow us the appropriate runoff to mold the part. When the part is produced, that flange will be trimmed back to ~1" around the perimeter allowing for bonding.
This is designed to be a bond-in, non-removable part. the flange we leave is for bonding purposes only and can be trimmed during installation as needed.

Typical installation of a part of this nature would be to bond it in, fill the gap on the top side and surface and paint.

You used the terms epoxy it in... Yes, right idea, right approach, you are on the right track however there are adhesives more suited to this application... Urethanes, for example.

All this said, the skin is what we are focused on now and will produce. While we do, there will be lessons learned and info shared.

Best regards,

[toddc]

Here are few quick pics,

we have completed the tooling and pulled the first part out of the mold.

The weight of the carbon panel is 2.1 lbs, the weight of the stock steel sunroof is 12.2lbs.

I will say, this is not a fair comparison as the stock part is a 2-pc welded assembly with mounting hardware, etc. and the carbon skin is just that.

Another thing I will say is that we just found 10lbs of weight savings for those interested in pulling the stock sunroof without going to the expense of doing a roof swap.

We will be making a few more and building inventory and releasing this part to the general public soon.


Thanks for viewing and as always, open to questions.

Regards,

toddC

[smellslikecurry]

Can't wait!

[juanbenae]

Originally Posted by toddc

The weight of the carbon panel is 2.1 lbs, the weight of the stock steel sunroof is 12.2lbs.


toddC

Elom? calling Elombard....

[Flojo]

How is it fitted? Glued from below? How do you seal it from above?

[toddc]

Originally Posted by Flojo

How is it fitted? Glued from below? How do you seal it from above?

Great questions,

How it's actually fitted and finished by the end user will probably vary based on what shop is doing the work and their preferred method.

What we would do here is bond it in from the bottom, with one of the flexible adhesives from SEM or 3M designed for bonding dis-similar materials, then fill the gap in the top with the same. From there the panel to roof transition can be surfaced with common fillers, primed and painted. Or, with a careful eye, one could tape the edges to keep the carbon panel exposed and only paint the seam/transition.

Thank-you,

[smellslikecurry]

Hi,

Is there an eta?