"TrailTop" modular trailer building components

[rowerwet]

trail dog?
and thanks for the durability answers. I don't see me needing the whole kit, but an easy way to make the hatch would be great!

[KCStudly]

How is the seam made between the curved panels and the ply? If both the plywood and the curved panels rest on the flanges of the corner pieces, doesn't that mean the the cut curved panels butt to the ply? If correct, I assume that there is a batten backing each of these joints.

[Hardryder56]

Jeff,
Based on what I know about fiberglass and seeing the way you designed the system I figured it was going to be strong. Don't worry about anything but your Mom, Moms are important. Prayers and Good vibes going out for her.
Tom

[jscherb]

Jeff,
Based on what I know about fiberglass and seeing the way you designed the system I figured it was going to be strong. Don't worry about anything but your Mom, Moms are important. Prayers and Good vibes going out for her.
Tom

Thanks Tom. My sister (she's an RN) and I have worked with the doctor on diagnosing the problem and what initially was a life-threatening situation breaks down into something non-threatening plus some related (and likely manageable) issues, so things are looking up here. I hope to be able to return home by the end of the week. Until then, I'll probably have internet access for my computer probably only once a day, so if it takes me a little longer to respond to questions and comments that's why.

[jscherb]

How is the seam made between the curved panels and the ply? If both the plywood and the curved panels rest on the flanges of the corner pieces, doesn't that mean the the cut curved panels butt to the ply? If correct, I assume that there is a batten backing each of these joints.

Since I'm traveling I can't take any new photos right now to illustrate how those parts go together, but all of the TrailTop parts go together the same way so I can use these photo/drawings of some sample pieces on my workbench to explain. All TrailTop parts have recessed flanges on them where the skins attach. In the photos below, the horizontal piece overlaps the corner piece, it sits on the recessed flange of the corner piece. On the horizontal piece, the flange has been trimmed back to clear the flange on the corner piece.





So to answer your question about how the 12" radius skin attaches, it's exactly the same - imagine in the above photo/drawings that instead of a small 3.5" radius corner piece you've got a larger 12" radius corner piece, and instead of the 3.5" radius horizontal piece, it's a 12" radius skin piece. The skin piece also has the recessed flanges, you can see the flange on the skin piece in this next photo and you may be able to see how it's trimmed back to clear the flange on the vertical piece:



The 12" radius skin piece has flanges on both sides, which are used to mount the flat plywood skin on each side of the curve. But what happens if you cut the 12" radius skin piece to say 60 degrees, rather than the 90 degrees as it's molded? You'd be cutting off the recessed flange on one edge, so you replace that flange with a piece a 1/4" plywood. You would epoxy the new flange to the underside of the curved skin piece, so the result is exactly like the recessed flange you just cut off (except it's wood instead of fiberglass).

So basically all joints between the skin and the TrailTop parts are done with a recessed flange, and in cases where you might cut that flange off of the curved skin piece to support a different radius, it's a simple matter to recreate the flange with 1/4" plywood.

[KCStudly]

Thank you for the very thorough answer, which was essentially, yes, you glue a batten over the butt joint.

[jscherb]

Thank you for the very thorough answer, which was essentially, yes, you glue a batten over the butt joint.

I thought the detail-oriented folks would like the full answer .

And to use your terms, I'd probably say "yes, you glue a batten UNDER the butt joint ."

[jscherb]

Thanks everyone for all the suggestions about what to call the concept pictured at the bottom of this post. Here's a list of the suggestions:

Trail Top Curveline
TrailTop JigSaw
TrailTop Outlander
TrailTop Outback
TrailTop Pod
TrailTop Utili-Pod
Trail Finder
Trail Rider
Trail Dog
Northern Trail
Northern Comfort
All Trail
TrailTop Base Camp
TrailTop Boondocker
TrailTop Nomad
TrailTop Frontier ST (ST=Saw Tooth in hour of original design)
TrailTop Overlander


I like rowerwet's suggestion - I think I'll use Trail Dog to refer to this concept from now on...

[jscherb]

Two weeks ago when I posted the TrailTop clamshell tent idea, I said that I had been thinking about making a sewing machine my next "power tool" acquisition so I could sew prototypes of some of the fabric ideas I've drawn. I'm happy to report that I now have a sewing machine. It's a very heavy duty model more than capable of sewing through many layers of thick canvas. I've been practicing on it the last few days.

The machine was my father's. He bought it used about 25 years ago to sew canvas for his boat, so it's a very rugged and capable machine. My mother kept it for the last dozen years "just in case she needed it", and had it completely serviced two years ago. I would never ask her for it, but when I told her I wanted to learn to sew so I could do canvas-type projects to go along with my Jeep and fiberglass designs, she decided it should be passed down to me. I'm thrilled because it's a great machine and it's got a great family history - my father did fantastic work with it equipping his home-built 36-foot trawler with side curtains, bimini tops, etc.

Funny family story - my mother had her own sewing machine as long as I can remember, but she would never let my father touch it because she was afraid he'd sew heavy canvas and ruin it. So he went and bought his own heavy-duty machine and then told her she wasn't allowed to touch his sewing machine either .

I've already got my first project planned, although it's not a TrailTop design, it's something for my military trailer kit. I'll post that plan in the military trailer thread when I start it.

But I'm still intrigued by the TrailTop clamshell idea, and I may tackle that one as well. Here are some updated sketches, the first is a roof-top clamshell tent:



And here's the exact same fabric design with a flip-up cover/tent that would work directly on a Dinoot trailer tub:



I'm working on a few more pop-top concept drawings for both campers and RTTs, stay tuned...

[Watercamper]

Please remember that it's called a "thread injector", not a sewing machine

[Hardryder56]

Jeff,
You Sir are a true Renaissance man. Can't wait to see what you come up with next.
Tom

[jscherb]

Now that I've got a sewing machine and I'm getting comfortable using it (at least on practice scraps of fabric), I'm working on the details of some TrailTop poptop and clamshell concepts.

I found some photos of a 1972 "Compact Jr." trailer; it had a pop-up roof:



Those photos supplied some of the inspiration for the drawings below. Using TrailTop parts to frame the top of the pop-up, here are some pop-top ideas:



These are based on a Jeep-tub trailer and have a barn-door in the Jeep-tub tailgate opening in the back, but that's only because that's what I've got in the workshop right now. Of course a TrailTop doesn't require a Jeep-tub base, so these concepts apply to pretty much any camper that has a large enough flat roof for a decent sized pop-up (even if the camper isn't based on TrailTop parts).

The vertical pop-up offers 6' of headroom as drawn; the tilt-up offers about 7' at the high end.

The top frame of the popup is made from ordinary TrailTop straight pieces and 90-degree corners. The fill panel would be 1/4" plywood. The popup would be slightly narrower and slightly shorter than the flat part of the top of the main camper shell so it would have a flat surface to seal against when it's closed.

The mechanism for the tilt-up would be pretty simple - hinges at one end and gas struts at the other. For the vertical pop-up, there are several types of mechanism used by the commercial examples of clamshell RTT's like the Maggiolina, so a mechanism like one of those could be used.

[jscherb]

These clamshell ideas are exactly the same size as the pop-ups on the full campers in the previous post. Since the camper concepts I drew are based on a Jeep-tub trailer, they're the same width as the Jeep, and the length as drawn is correct to work on either the camper or the Jeep, which in this case is a 2004-2006 Wrangler Unlimited with one of my Safari Cab hardtops on it.



Because the dimensions are the same, the exact same fabric pieces are used in both the poptop camper and the RTT clamshell. The only real difference between them is that the RTT clamshell has a bottom half, which is the same as the top frame, except upside down, and probably thicker plywood and a little more structure since it has to support the weight of two people. Mechanisms could be the same as the camper poptops

[Watercamper]

I had to google RTT - Roof Top Tent (it was easy to figure out that it wasn't an acronym for the Reynolds Transport Theorem But I couldn't find good enough info on the mechanism. I'm interested in seeing/understanding it. Do you have a site with more info? Thanks!

[jscherb]

I had to google RTT - Roof Top Tent (it was easy to figure out that it wasn't an acronym for the Reynolds Transport Theorem But I couldn't find good enough info on the mechanism. I'm interested in seeing/understanding it. Do you have a site with more info? Thanks!

There are several types of mechanisms commonly used in commercial clamshells, and these could also be used for pop-tops on campers.

The original Maggiolina uses a screw jack mechanism; the numbered sequence is from their website. There's a small crank on one end, and I'm told it drives the front scissor directly and the rear scissor is driven by a bicycle chain running from the front mechanism to the back.



The Maggiolina Columbus, which is hinged at one end, and their Airtop model (vertical lift) both appear to use a gas-strut assisted folding leg system:



There's a flash animation on the Autohome site showing how the roof of the gas strut model gets raised, these three frames are from that animation. Apparently you release the rear latch and the gas struts push the back up, then you release a front latch and the front goes up.



The gas strut mechanism is simple enough to DIY-build, it's pretty much two pieces of nesting u-channel, a gas strut, simple backets to mount it at each end, and some bolts. If I decide to build a proof-of-concept, this is the mechanism I'll probably use.