JK 4-door to 2-door long wheelbase conversion.....

[Duder]

Is anyone a member of SEMA that uses the tech transfer program? I am interested to see if the CAD data for the top is available...

Yes, and yes:
Year Model Component Name View Sample
55128 2009 Wrangler Hard Top Assembly No Preview Available
55129 2009 Wrangler Hard Top Assembly No Preview Available

You need to submit a request to Chrysler to get the models though, and I'm sure they evaluate the identity of the requestor and the intended purpose...might be a bit hard to actually get that file. Unless you are an aftermarket manufacturer, or know someone who already has a copy.

Why not just remake the entire top in carbon fiber while your at it. I wonder how light that would end up being?

If you went this route, you could use the factory top(s) as a male mold aka plug, with no need to do a custom buck as you discussed before. Use the front of the 2-door top and the rear of the 4-door, like was suggested. Cut where you want, fasten them together somehow and fill in the seam. Then spray the whole thing with mold release and gelcoat. Lay up fiberglass over the new hybrid top, reinforce with ribs and expanding foam, then pop the mold off of the hybrid top. Now you can lay up carbon or glass into a female mold and end up with an identical surface finish to the original top, if you do it right. You can even vacuum bag the new top layup for better quality and reduced weight. I've made several fairings this way and it can work well if you use the right materials and techniques.

 

[Metcalf]

Thanks for the input. I do think using the stock top could be used to mold, however, if I was going to go to the trouble to make a new top I would most likely want to change a few things......

-Smooth, non-ridged top panel. This way I can run a large thin film solar panel on top
-Build the top panel so it can be insulated with a foam filled honeycomb element. This should be quieter and much stronger than the stock top.
-Eliminate the side windows, or maybe have a few options.

I have been doing some research into composite construction. Fun stuff.

 

[Duder]

You might be able to still use the original top(s) as a plug with those three changes.

1. Sand down / cut off ridges, fill voids if necessary
2. Lay up the outside layers first in the female mold, then the honeycomb, then inside layers of carbon/glass
3. Plug holes in original top(s) with plywood & body filler, texture paint to match?

Making your own molds and parts gives you a lot of freedom with composites. Granted, it will always be harder to make attachment points with a composite top vs. aluminum. One way around that is to add threaded inserts with spreader plates between the layers of fiber as you're laying up the part.

 

[Metcalf]

I have my doubts about trying to mold the entire JK top in one piece since the factory top is made up of about 10 (?) pieces all glued together.

 

[Metcalf]

Quick question.

Can you go directly to making the female mold out of something like cnc machined MDF? I'm thinking along the lines of a 'shallow' part like the side panels. How would you have to prep the MDF to pull a part from it?

 

[Duder]

I would think machined MDF might be a good backing for a female mold, but I've never tried it. You would need to probably spray it with gelcoat and make sure the final surface is very smooth for pullability of the laid-up part, not to mention needing some sort of mold release. The vertical walls of the MDF female mold would need a draft angle as well, the value of which would depend on the "draw" or depth of the part you're making. You could always give it a try on a small scale, and go bigger if it works out!

 

[LUISJG]

A plug and mold would be fine if you intend to sell some,, but if its just for you,, its lot easier to make the top over your jeep with plastic laminate
the kind they use to cover trailer home doors or comercial bathroom walls, runing an aluminum frame witll give you the stifnes underneath, once its done, then you cover it with epoxy and fiberglass matt, 2 layers ,then fairing ,sanding and paint. for the front windshield bracket you can use a best top channel that available for safari or bikini tops.,, its a project , and you can get nice results,, I seen it done in the past on tj jeeps.

now if you want to get creative,,,make some tent pull out from the the rear side windows, one bed pulling out on each side, with its own acordion type
enclosure. ..:ylsmoke:

.

 

[Metcalf]

The other thing I want to do is eliminate the front freedom top panels if I make a new top....

I was thinking that the inside of the MDF female mold could be sprayed with epoxy to seal it? Then sand and buff it smooth......a few layers of wax and it should be good to go? I think the cnc'd female mold could work out really well if you wanted to vacuum bag the composite since the the 'top' of the mold would be flat and allow an easy seal to be used.

Plus, its a good excuse to have a cnc plasma/router table at home

 

[AhmicAndy]

Just wondering? How many of you guys actually would buy one of these tops (with real cash) if one was possibly made? Has anyone come up with cad drawings for the current JK top yet? I have the equipment to do this but its a pipe dream without A. several copy's SOLD and B. the exact measurements for the vehicle. These molds are not cheap but once created would be useful for many pulls. I don't get in to the Fiberglass/composite process but I design/cut molds for tooling in the marine industry.

Cheers :beer:

 

[ActionCamper]

Part of the ActionCamper Unlimited conversion are the bolt-on half doors. As soon as production runs we'll sell them maybe together with a complete bolt-on bick-up kit. We are aware the some ActionCamper owners plan to use the Jeep as a pick-up while not travelling. The bolt-on half doors will come with optional access doors.

 

[X-plorenow]

Is anyone a member of SEMA that uses the tech transfer program? I am interested to see if the CAD data for the top is available...

I am and can if you haven't gotten this already.

 

[Metcalf]

I believe that bestop made all the J8 soft tops....

 

[Caoboy]

You coul call up ursa minor and see what they can do for you. Maybe they'll make a custom fiberglass door insert and extend the top to work for you.

 

[Metcalf]

You coul call up ursa minor and see what they can do for you. Maybe they'll make a custom fiberglass door insert and extend the top to work for you.

Sure, this was more of a thought exercise than anything.

I think something like this would have a market, but it would be a small niche market. If they ever offer a factory diesel in the USA I will get more serious about the idea....

 

[JWOK]

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