Finallly... I avoided rear hatch delamination. Alternative struts location.

[wwdwgs]

I installed new weak shocks in pairs and mounted them to the hatch floor hooks. Hatch opens 26 inch clear at the center. The interior light doesn't work yet, as well, as the defroster. But I'm working on it.
Here's how it looks like.

[originalowner]

That is a very clever solution.

[djnolan]

Looks Brilliant, the strut is pushing on the hatch instead of pulling.
Do the hatch struts attach to the hatch in the same place or did you change that?
Also is it the same strut cartridge or did you change that?

[wwdwgs]

in a nutshell:
originalownner,
The idea wasn't mine - I saw a video, where a guy (an engineer btw), "unhinged" the stock-length gas shock from the body/roof area and attached it to the cargo hooks. The drawback is that the hatch opening height was about 16 or so inches. That was very inconvenient to load and unload anything. I wanted to increase the opening height. And, you can not use stock struts in this configuration, because they will push so much, that you may shatter the glass, trying to close the hatch. Those from Jeep, mentioned 100 times on this forum, may work.
djnolan,
Yes, the shocks are attached to the existing points on the hatch itlself.
The obstacle was in figuring out the compressed length (similar to stock with stock shocks) and extended. If I wanted to increase the opening length, the shocks must have long travel, which is not possible with allowable compressed length.
Because of these dimensional restrictions, it's impossible to use stock-length struts.
Because of different mounting points, the "new" struts must have less than 65 lbs force (stock struts have about 60-70 lbs depending on the side - left side may carry more load because of rear wiper assembly).
So, I "weighted" the hatch at mounting points on the glass/frame side and started to play with the aftermarket struts.
I put weaker struts directionaly opposing each other, adjusted the total compressed length (very important).
The strut assy you saw on my video are rated 30 and 40 lbs. It's better to have both "upper and lower" struts with the same ratings - 40 lbs. With this ratings, the hatch must be pulled up until the struts kick in and push the hatch open.
If the hatch is equipped with the wiper assy, then the LEFT side must be "upgraded" to 45 or so lbs.
I didn't want to play with struts higher than 40 lbs, just because I didn't want to increase stress on the hatch upon closing it.
The struts are held to each other by metal "jacket", which wraps around them and prevents any movement.
Since these new struts assemblies don't conduct electricity for the light and defroster, I'll run wiring and new switches.
The reed switches, that I saw on one video, don't work well - they overload and "burn" after repeated use.
The main problem of possible glass-frame delamination is, therefore, avoided.
The hatch opening height is similar to stock's one.

The compressed length is about 16 1/2" - 17" (center to center) - I just don'r remember after all these experiments. It could be measured when the hatch is closed. Extended - about 31 1/2".

The drawbacks of this "alternative" set-ups are:
1 - a need to run wires and switch for the dome light
2 - a need to run wires for the defroster
3 - more weight
4 - unknown longevity
5 - more labor
6 - more cost
7 - less favorite drinks left in your fridge

The benefits:
the glass/frame separation is stopped, or, at the least, lessened.

[onZedge]

Thanks for sharing this. Very interesting solution.

[wwdwgs]

update:
I finally fixed the light. I added a magnetic switch to one vent on the left side like so:



and a short video.

[Monkey Wrench]

if a reed switch handle the amp load then you might try using a small relay and let the reed switch control the coil of that relay, reducing the current load?



attached are 3 pics , this is actually a rod used in a machine to compress a heavy spring to change sanding belts. It is not quite what I was thinking but its shape is somewhat similar.
Im posting it as basically a visual of what Im thinking.

see how there is a little flat part that can lock the rod once it goes even slightly over center on its pivot?

what Im thinking is if the shocks could be intentionally a bit weak and then once you can get your hands inside you flip the rod over to its lock point, thus lifting and solidly holding the hatch up.

when the rod is unfolded it sits agaist that flat part, soimilar to the picture. when it is folded it basically folds in half as you close the hatch.

this prop woulf then be holding the hatch open but with the help of the shocks, so stress is reduced, and maybe only one side has, or needs, the foldable prop rod.

I got the idea when my brother made one.. he had a triumph GT6 similar to a spitfire, the whole hood and fenders lifts.. so he made this rod which looked quite similar to this picture, the rod simply locks by folding open, goes a tad beyond center and then sits against the little flat part ,, the flat part looks similar to this pic. when he closed the hood, he simply moved slightly the rod causing it to go "under center" and then it folds into two segments, basically.

in this picture the rod is actually designed to be acting upon the hole in the end and that shouldner bolt near the pivot.

for the hood prop it would be attached to the car and to the hatch near the two ends of the rod. that bolt is not part of it..

the flat bar is easy to procure.. it might also woirk fotr the 944 hood, mine has weak shocks.

some volvos have a beautiful feature built into the hood hinges, you flip a little lever and then the hood can open to a completely vertical stance, this helps see a lot better.

while on hood hinges, Oil them ! ive seen hoods break right off at the hinges simply due to lask of lube, it really leaves the guy in a predicament,, so what do you do , try to remove the hood? let go and scratch yourcar to find help? try to go home without it? Its a bit of a pickle to get into and the prevention is so easy. it just needs a drop but you know,, oiling hinges , its never a very urgent job.... until this happens.

Sorry about thre pic sizing its a bit hard to see

I might not be completely understanding what you have done , it sounds like you have tied two shocks together to affect the open and closed distance and since you then have two pistons , it can retract to less than half its extended length. smart thinking! . You also moved the attachment point not on the hatch but on the car, is this right?

normally any air cylinder by desogn can only close to a bit more half its extended length becauese the rod needs to go somewhere,
so it seems you used two , thus solving that issue.

[wwdwgs]

MW.
Right, the gas strut pivot point on the hatch remains untouched. The other pivot end, on the c-pillar, is "moved" to the cargo hooks - a new location.
I know that the way I " tied" two gas struts is not ideal. more weight, double price and hard to tie them neatly.
Your idea about foldable-collapsible props would be good, if you can use one. In our case, the rear hatch is heavy and requires support on left and right sides. If you were to install two props, they you'll have to either use both hands to "collapse" them, or collapse one of each side separately, which, I think, is tedious.

[wwdwgs]

MW, also there are many aftermarket parts that are identical to Porsche's, used for other "affiliated" makes, like VW, BMW, Audi. I replaced one sensor from BMW, that is identical in size, shape, function and specs, but has a different part number, same manuf., I paid about 1/3, which is a big "negative" margin. Even some Volvo parts are "interchangeable". I know that it's hard to find these parts. If you have questions, just ask. ))

[Monkey Wrench]

my suggestiin siunce you could have trouble finding a volvo hood lamp switch . , insted find any older thermostat.. heres an example. probably anyone working around heat and AC will have one hanging around.

just use the bubble as your contact. chuck the rest. maybe hide inside the frame of the door or similar? you could JB weld it in place somewhere perhaps.

id want a switch if there isnt; one on the lamp itself to turn oit off, say if you park at some weird steep angle or similar. maybe it woudl wanto stay on.. one could experiment a little. tape it in varius places see what works best.

[wwdwgs]

MW,
I'm past the mercury tilt switich. I used the switch as pictured above in my previous replies.

[Monkey Wrench]

It was slick how you 3d printed that vent part, do you create the file yourself?

a friend says he will give me his older 3d printer but I know nothign about writing the files and that might be a huge learning curve. Ive found sites where the files are shared and some pretty odd hard to find parts being uploaded feely and there was a lot that you could just download, so that doesnt; require the 3D software skills.

This might be helping as a way of obtaining some of those unusual parts which you can't just buy easiily.

glad that worked out. it looks very profesional like that. the double ended cylinder package looked nice too.

[wwdwgs]

MW,
the file, rather the 3d model, was done by myself. The first version was like a case that "housed" a reed switch and a relay. Since I found a different type of switch, I redesigned this "mount", as I call it. There are are free software programs (apps), that you can download, install and use, or there are some sites that allow you to build a model online. Once the model is properly built and converted to appropriate file (.stl, or .obj, or .step), then it can be saved on a flash drive and transferred to the 3D printer.
If you can get a 3D printer, that's great. I don't have one - I had to use a local library, which offers 3D printing services. This mount costed whopping fifty cents. So, why not?!

[Monkey Wrench]

i tried taking a course ofn google sketchup , covid came and the course stopped but I did learn a little pereaps its more suited to carpentry and thats where we were focussedin learning.

I have to be involved in things like fixing burning tabbles CNC routers, they use more basic files. I don't write them. I see a 3D grinding machine now so Im curious what it can do , sounds fun. I worked fro a place that built houses with CNC walls trusses stairs doors windows , it all originated in a front office fullof computer guys and they would create the whole house then send it to site for assembly, they could do neat ost and beams with very interesting joinery cut by computerized robots and that was all 20 years old , ten years ago .. they had a 5 axis router , it was a neat machine..


so other than 3 d printing whic h adds material there are other methods involving material removal.. Its getitng very interesting.

using the old analogy of "building a better mousetrap," I can see how the ability for people who don't even meet to be able to combine efforts and perfect designs by downloading and altering the file in creative ways and then sharing them back up to a server.

I think it can result in a huge advamcement , throw in AI to that mix, well Im not sure but my prediction is all this will combine in ways we can't yet forsee.

hard to imagine we humans can do all that but we can't stop wars or limit how all this technology is going to be used.

you could probably send that file and have metal part made from it , one way is the "wax replacement method" the form woudl be molded in porcelain, pastic burned out and metal used to fill the void left. also it could be done with other CNC eqqupment that builds by welding or removes by grinding.. I find it all fascinating.

[wwdwgs]

one man said, that he was told "by a higher authority", that when we cooperate, we prosper; when we compete we end up in the current state.

[Monkey Wrench]

Big nod to that !
"all I want is my peace of mind"

I feel this nice old song resonates the meaning quite well

https://en.wikipedia.org/wiki/Peace_of_Mind_(Boston_song)

utube link
https://www.youtube.com/watch?v=edwk-8KJ1Js

[Dano944]

If you still get water leaking into the very back of your hatch, let me know. I think I solved the problem. I got terrible leaking just by pouring water in the rear spoiler, and when water vented through the drainage slots, I found out how water leaks in. Just a poor Porsche design with between the drain slots and the lack of sealant between the spoiler and rear hatch body.

[curtisr]

Originally Posted by wwdwgs

one man said, that he was told "by a higher authority", that when we cooperate, we prosper; when we compete we end up in the current state.

As an aside, it took Microsoft years to figure this out.

[wwdwgs]

Dano, those drain slots in the spoiler are small. I would make them 4 times larger. Let it drain, let it drain, let it drain...

[Dano944]

Originally Posted by wwdwgs

Dano, those drain slots in the spoiler are small. I would make them 4 times larger. Let it drain, let it drain, let it drain...

I agree with you. The problem I observed is the water tries to flow through those slots, then backs up and seeps between the rear spoiler and the body, then it flows over the weather stripping along the hatch body. If those slots were larger, I believe the water wouldn’t have time to overflow the weather stripping.