Converting a factory JK/JKU hardtop to modular

[jscherb]

A while back I picked up a side panel that bad been broken off an early model 2dr hardtop, I got it to use for prototyping the early 2dr window retrofit kit. It looked like this when I got it:

Shortly after I got it I repaired it and put a flange on the top mostly to add some stiffness to the panel, and that work turned out to be the beginning of the planning for this modular conversion project.

The other day I put a bolt flange on the back of it to make it compatible with the modular hardtop conversion. In this next photo the roof and rear panel are from the late model hardtop but the side panel is the one above and being from an early model "small window" hardtop it shows the interchangeability of the modular parts.

And with that interchangeability comes the ability to reconfigure the hardtop for different uses, here I've swapped a cargo hatch panel in place of the window panel.

 

[Metcalf]

I've done a number of forms for roof panels, but none were intended for the stress of forming metal, so my construction techniques probably wouldn't help you. The most recent one was the roof for the JK Safari Cab project, I posted a lot of detail on the roof form construction in that thread.

I'll look it up. I am not so concerned about the female mold/form, but rather the finish on the male plug that I will be making it from. The plug will not see any stress, I think I just need to get the finish as good as possible to that transfers to the female mold/form ( that will see some impact stress ).

 

[jscherb]

I read through the how-to (thank you for the great detail, not only in explaining every step of the process but in coming up with a process that doesn't require a whole bunch of specialty equipment or advanced techniques) and I've got a question about the seal between the parts. I know that you didn't actually install them on this top so there's no pictures, but could you detail what kind of seal you would actually use? I assume you used a similar seal system for the other tops you've made in the past, maybe a picture of that would help?

I'm just not able at the moment to wrap my head around how the seal will sit in there (is it just a flat seal like what is between the bottom of the hardtop and the tub?), but I'm probably just missing something clever.

Because of the process I described for making the flanges, they should mate perfectly so weatherstripping between the parts can be done with simple flat weatherstrip. I recommend 1/8" thick x 3/4" or 1" wide, self-adhesive. McMaster-Carr #93725K56 would be a good choice (http://www.mcmaster.com/#standard-rubber-weatherstripping-strips/=13hdtqm).

I'd stick the strips to the side panels, that way when they're removed the weatherstrip is removed as well. After you stick it on you can use a knife to cut the holes for the bolts to go through.

 

[Ryan1035]

I'm so glad you posted this, I was truly at a loss for how to efficiently build matching flanges to tie all the pieces together. I also had no clue about the variables in types of resins that were necessary. Thank you again for the outstanding information!!!

I'm still looking into a way to gullwing the side panels, as I'd love to have full access as opposed to being limited to a hatch.

 

[jscherb]

I'm so glad you posted this, I was truly at a loss for how to efficiently build matching flanges to tie all the pieces together. I also had no clue about the variables in types of resins that were necessary. Thank you again for the outstanding information!!!

I'm still looking into a way to gullwing the side panels, as I'd love to have full access as opposed to being limited to a hatch.

I did some experimenting with the idea of gullwing side panels a few years ago on my modular LJ Safari Cab. These photos show the side panel mocked up as a swing-up. I didn't actually convert them to gullwing panels, I was doing the experiment to determine if gullwings were feasible and to do the design work on any changes that would be required for them to open, close and seal properly.

In order for these to seal properly, the flanges need to be done differently than described in this thread. I can work up a description of the differences and maybe a drawing or two if people are interested in doing this to their factory modular conversion hardtop.

 

[Ryan1035]

The sealing was one of my concerns, I was considering making it with a lip on the hatch itself to overlap the "frame" and also using a single proper hinge that will accommodate for the curve in the side panel and using the rear glass lift support to make it easier. I also have some of these latches that never got used for original intended purpose that I think would work fairly well.

 

[jscherb]

The sealing was one of my concerns, I was considering making it with a lip on the hatch itself to overlap the "frame" and also using a single proper hinge that will accommodate for the curve in the side panel and using the rear glass lift support to make it easier...

One type of hinge that could work well for this application is called a "hurricane" hinge. It forms its own drip rail, they're commonly used for teardrop galley hatches.

I built a teardrop topper for my Jeep-tub trailer a few years ago and used a hurricane hinge for the hatch. It worked out very well. Some work-in-progress photos of that project:

One other nice feature of this type of hinge is that they slide apart, which would make it possible to remove the hinged side panel.

 

[Ryan1035]

Will it remain engaged when the "hatch" is opened past 90*?

 

[jscherb]

Will it remain engaged when the "hatch" is opened past 90*?

Some open past 90, some don't. The one I have allegedly opens to 120 degrees, although I haven't measured the angle so I haven't verified that.

 

[jscherb]

This morning I finished up a proof-of-concept of a removable hardtop window idea (please make believe the black panel in these photos is clear or tinted polycarbonate, I made this prototype from an opaque panel I had on hand). The panel gets secured into the window opening with 6 latches, and can be removed/installed in under a minute. No changes to the hardtop are required, other than removing the factory window.

Since no modifications are required to the factory hardtop for this, the factory window can be replaced at a later date by bonding it back in with adhesive just as it was from the factory.

I made this as a proof-of-concept of the removability concept, and it seems to work well, so the next step is to make one with an actual window instead of an opaque panel.

Other possibilities for the concept are possible - for example a cargo compartment with a gull-wing door that could be swapped in place of a removable window. Or a screen. Could be a whole series of removable options - clear or tinted window, solid panel (either for a panel van look or maybe for mounting things on?), a storage compartment with a gull wing door, a screen panel, removable frame with roll-up soft window, ????

The hardtop in these pictures is the one I did the modular conversion on, adding this removable window concept could be a whole new chapter in Jeep hardtop configurability...

 

[jscherb]

I would LOVE this. I'm very seriously considering doing the modular conversion you outlined. Between that and removable windows, I couldn't ask for more out of a top. A question: with the top broken down into pieces and bolted together, do you think there is any loss in rigidity? Any problems with additional roof loads? I have tracks bolted through my hard top for a roof rack and I do carry stuff up there..

If you build the flanges well, the assembled hardtop will be no less rigid than before you cut it into pieces, in fact it might be slightly more rigid. The reason is you're cutting a thin section of fiberglass and replacing it with much thicker flanges that form an angle - that's more rigid than the original fiberglass, and once it's bolted together it's very strong. In the photo below I'm manhandling the assembled top, no special treatment is required.

As for a load on top, the assembled top won't be any less strong than the factory top, but having said that I wouldn't carry a heavy load up there without tying the roof rack to the roll bars so the fiberglass doesn't get stressed by the weight - I'd do that with the factory top or the modified modular top, either way I'd be more comfortable with roll-bar tie-ins for anything but a trivial load.

 

[jscherb]

Following up on the removable window idea, here's a removable storage compartment concept with a gullwing door. It would latch in place just like the window does.

Compartment assembly:

In place:

Maybe a Molle grid for the back panel?

Or a grid for gear storage?

Or a retaining net?

The compartment would be a simple molded fiberglass box, with any necessary clearance for the roll bar inside and a locking gullwing door. Or it could have a swing-down door that serves as a table:

 

[cj454]

Just wondering what top is the AT top?

I am looking at the Ursa Minor tops but the price is way to much for me to justify the cost.

I loved the write up and the detail. I am not sure I would want to tackle the project my self as I am not sure I am skilled enough or patient enough, I would love to hear you ideas on some sort of carpet top for the JKU. I see the ursa minor and think those are great! also the new ones from AT in arizona. while I would love to own anyone those the price is torch for me right now. Being over 60 I need to get up in the night and would like not to have to leave the vehicle. maybe you have thought about some variants on this theme "roof top camping" That are not being done right now. Seems to me that if you could install fold down tailgate ( I know they are available) you could perhaps create along standing area with a similar concept to Ursa minor j130 I would love to hear what you thought about or perhaps will think about. anyway excellent job, excellent write up, and very enjoyable reading about the process!

 

[jscherb]

Just wondering what top is the AT top?

I think he's referring to the AT Overland JK Habitat flip-top for the JK, which has just been discontinued: http://www.expeditionportal.com/for...abitat-No-Longer-in-Production?highlight=j180

 

[JDaPP]

For the seam between the top piece and the section that contains the rear flipglass, any issues with leaking or is the weather strip sufficient to stop the leaks?