Cut out roof, replace with foam core fiberglass pop top DIY

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trip_south
I am smitten with my van
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Cut out roof, replace with foam core fiberglass pop top DIY

Post by trip_south »

Hello,
I've been thinking about this idea for a while now and was wondering if anyone had experience or knew of some examples of a diy pop top made from glassed rigid foam insulation, preferably with hard sides. I've seen at least one Astro on this forum with most of the roof cut out and a pop top installed but for the most part it seems pop tops aren't so popular or profitable for these vans. Perhaps doing it myself will be the best way, using as few tools as possible and no welding preferably. Here are some questions I'm trying to answer:

How big of a cut to do?
What cross beams exist and should those be cut?
Is rigidity and roof strength a concern and if so how should it be addressed?
Once cut how should the edge be lined in order to accept the top?
How should the foam be shaped and glassed?
How should side panels be laid out and integrated with the roof?
What kind of lifting mechanism should be used?
What kind of hinges/folding mechanism should be used?

So far I'm thinking of lining the edge with some sort of aluminum or steel L-beam then fasten another L beam to that to form a "ledge," upon which the top is supported.
What are your thoughts? Thanks in advance for your advice.

Inspirations:
http://www.expeditionportal.com/forum/t ... ild-thread
http://poptopcamper.freehostia.com/
Jesse
99 AWD Safari
99 Safari AWD -> 4WD slowly Update: Auto 4wd, 2Hi, 4Hi work, no luck with shifting to 4lo
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Herbie
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Re: Cut out roof, replace with foam core fiberglass pop top

Post by Herbie »

You can look at my build thread for photos of the original roof, how I cut it, and how it's reinforced. Be sure to click on the linked albums, as there are a LOT of extra photos.

Generally:

There are 3 main ribs. You'll need to cut at least one or two. You should definitely reinforce the area - I recommend a ring of steel channel or tubing, similar to how the GTRV system works. (Also can be made as a convenient way to hang the upper bunk.) This is one area where you might need to farm out welding - I can't think of a good way to do this with cold-fastening only. Rigidity of the roof in general is important for crash-worthiness and to keep the van body tied together of course, but there's also the problem of "oil canning" on the parts of the roof you leave intact. The GTRV design leaves a portion of the roof intact for the upper bunk - until/unless you reinforce that section of steel, it will not support even a single person in the upper bunk. I screwed/glued two layers of 1/4" plywood into this area as reinforcement.

If you cannot find an existing pop-top for your Astro/Safari, the next place to look would be for a hard-shell roof top tent. Look at Maggiolina, James Baroud, etc. One of these could be glassed onto a van roof and then you have the top, lifting mechanism, tent, etc. all done. Colorado Camper Van has also made good use of fiberglass high-tops and turning them into lifting tops instead of permanently-mounted. These, at least, are available molded for the Astro/Safari, and you could probably get a good deal on a junkyard cut-off.

If you're determined to build from scratch, then I wish you luck. It will be 100's of hours.

Lift mechanism options include a VW-style 6-bar linkage (V-top), or any of a number of scissor/x-lift mechanisms (powered or manual/spring-assist) a la Sportsmobile, Colorado Camper Van, etc. Generally, direct-lift (like Alaskan campers) won't fit in a van environment, but you might be able to make it work. I don't know if anyone has attempted a hinge-lift (hinged lifting panels like 4 Wheel Campers, older Tigers, etc.) in a van-sized package. These all have their own strengths and weaknesses.
"My minivan is cooler than your bro-truck"
2003 Astro AWD Astrolander/ZMB - GTRV Top Transplant, 4" OLV Lift, NP233 T-case, evolving interior
1995 Safari GTRV Organ donor - gutted and gone.
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Topic author
trip_south
I am smitten with my van
Posts: 28
Joined: Wed Jan 13, 2016 8:10 pm

Re: Cut out roof, replace with foam core fiberglass pop top

Post by trip_south »

Thanks for the reply. Your build thread and example were big inspirations for deciding on a Safari.
99 Safari AWD -> 4WD slowly Update: Auto 4wd, 2Hi, 4Hi work, no luck with shifting to 4lo
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