J8 Expedition Project:
- Thread starter Scott Brady
- Start date
Dan Grec
Expedition Leader
Hey Martyn,
A few questions about just the 'pop'-top:
1. Is it possible to but just the 'pop'-top separately? How much does it cost?
2. How much does it weigh? (as in, how much does it increase the weight of a stock JK Unlimited Hard Top?)
3. Is it possible to have any weight mounted on the roof, or is it strictly nothing? (I'm not thinking a loaded expedition rack, more like a couple of solar panels.. nothing too heavy)
Thanks very much,
-Dan
elcoyote
Supporting Sponsor, Overland Certified OC0004
1.The ""pop-top" section is not available seperately. It is integrated and made to work specifically with the lower section that we build. I am assuming that you are thinking of mating it to a factory hardtop. This would not be possible.
2. The total Habitat is about 100 lbs more than the factory hardtop
3. Strictly nothing. The torsion spring is made specifically for the weight of the top and nothing more. Adding any weight to the top will exceed the design spec for the torsion spring and could lead to premature failure.
jingram
Adventurer
Not criticizing, but that seems a bit short sited. You guys are known for overengineering things so it seems surprising. I know you guys were trying to keep aerodynamics up and were only wanting to work with a certain glass layup in order to keep costs down. All understandable, but the torsion spring is right on edge and can't even handle a couple of solar panels? I mean we are typically talking 5-10lbs per panel.
Was the torsion spring designed inhouse? Is there a heavier duty aftermarket replacement available?
Scott Brady
Founder
It is not short-sided or a strength issue, it is a simple physics problem.
The torsion bar can be designed for other loads, but it would be custom. If it has too much torsion, the stock lid will be impossible to close and will want to lift in the open position. So is it possible to run another 100lbs on the roof- sure, but it would require a custom application, and AT is already backlogged.
The torsion bar can be designed for other loads, but it would be custom. If it has too much torsion, the stock lid will be impossible to close and will want to lift in the open position. So is it possible to run another 100lbs on the roof- sure, but it would require a custom application, and AT is already backlogged.
jingram
Adventurer
I totally understand the need to engineer for a specific application, but we aren't talking about massive amounts of weight here and something that I would imagine would be well within spec for the torsion spring.
Sunsei Solar
I simply can't imagine that bolting on a 10lb solar panel is going to increase the weight enough where the torsion spring wouldn't be able to handle the additional load on the spring.
Typically stuff like this has a 20% threshold for overage and will continue to run to spec. I guess I was just wondering if that was the case here or is was the part truly engineered to spec with no margin for error.
Of course it makes sense, but so does running a couple of solar panels on top in order to top things off during transit. I mean in an application like solar panels, we are most likely talking stationary and through bolted (yes I am aware of the foldable non rigid panels) so what is the harm.
Dan Grec
Expedition Leader
Thanks for the replies
I thought the 'pop'-top would be essentially a stock JK hard top, with the roof cut off, and modified with the canvas and spring and whatever other hardware.
Am I wrong in this assumption? Is the top something custom you manufacture from scratch?
Thanks again.
-Dan
I'm a little confused on this... 'integrated and made to work specifically with the lower section' doesn't make much sense to me - are you saying you can't just bolt this roof onto a stock JK?
I thought the 'pop'-top would be essentially a stock JK hard top, with the roof cut off, and modified with the canvas and spring and whatever other hardware.
Am I wrong in this assumption? Is the top something custom you manufacture from scratch?
I didn't want to start an argument about this, I understand there must be design limitations for something so custom (& different) and the limitation is no extra weight.
Thanks again.
-Dan
jingram
Adventurer
Dan,
That is correct... this habitat makes absolutely no use of the factory hard top. The entire top is replaced so if you have a soft top only model, there are no additional purchases required. On the habitat version shown on the j8, you will notice that on the top does not have side windows the factory top has, rather it has those sections molded in and you can either add windows, a small cargo compartment or leave as is.
mk216v
Der Chef der Fahrzeuge
I agree with you...solar ******! :smiley_drive:
1leglance
2007 Expedition Trophy Champion, Overland Certifie
It does seem like solar would be the one thing most often added to a roof like this. Especially with hinges that run along the outside edge front to back that would allow the panels to swing out when the roof is flipped so they would face the sun again.
Scott Brady
Founder
Solar would not likely be a logical fitment to the roof of this application, given that when it is closed, you are likely driving (and charging), and when it is open, the solar panels would be facing the hood 
kb7our
Explorer
It's my understanding you get a basic rear window, not a tinted factory one like what is shown on all the J8 pics. Can someone confirm? So if you want a defroster and/or wiper similar to factory you have to order all that separately, inlcuding the factory tinted glass with proper cut outs.
I'd like to see what the options are for dark tinted factory side glass just for the passenger window. Also, what the driver's rear window area cargo option looks like.
Is there any kind of pad where you climb in before you get to the mattress area, or are you just crawling on the shell? Could get rough on the knees.