"TrailTop" modular trailer building components

[jscherb]

Jeff,
I'd like to ask what may seem to be a "rookie question"... I am a rookie though so please bare with me.
Now that your proof-of-concept has proven this is indeed do-able, what becomes of the "project trailer"?
Do you sell it? Do you dismantle the "clam-shell" to re-use as the top for the "roof-top tent"?
If you were to sell it, do you have any idea what the dollar figure might be?
This is purely academic because the dear wife has already informed me that a trailer will not grace our driveway...
I'm just curious is all... If the question is inappropriate please let me know so I don't repeat the error in the future.
Great thread by the way. Love the tilt-top.

Charlie

Charlie,

It's a fine question. I do most of my projects mostly because I enjoy the challenge of designing. Sometimes the goal is something I plan to use myself, like the Safari Cab hardtop and the CJ Grille Kit on my black Jeep that I showed the other day. But lots of times the project is just about the design challenge for me. I've done the TrailTop System project just because I thought there had to be an easier and quicker way to achieve professional-quality results when building a trailer or trailer topper at home. To prove that idea was fulfilled and the design was good, I had to make the molds for the parts, make some parts, and do some proof-of-concept builds. So during the course of this thread I built the teardrop trailer topper and then the hard cover for same trailer, and then I decided to do a proof-of-concept for the tilt-up canvas, which I've just finished. I did the tilt-up canvas mostly because I thought learning to sew would be an interesting challenge but of course also to prove that the TrailTop parts could be used for something like that. As far as I'm concerned the teardrop and the tilt-up have proven the concept and the design and met all of my design and functional requirements, so I'm done.

I never build anything explicitly to sell, and only twice have I designed and built something with the idea of having it become a commercial product (succeeded both times). I did not build the TrailTop system with either in mind, but if it becomes a commercial product that is ok with me, and if someone wants to buy my proof-of-concept builds I'd entertain an offer. But really once I'm satisfied the a project like the TrailTop system has met my design goals and functional requirements, I'm done.

At the moment, the components of the teardrop are stored in my basement, and probably the tilt-up will join them shortly.

BTW if I decide to build the clamshell roof-top tent, the way I've designed things, the tilt-up can be removed from the trailer and assembled onto the clamshell bottom half with only one small addition to the canvas components, and then it could be put back on the trailer and used as a tilt-up again. Most of my designs are modular and configurable like that.

Jeff

[jscherb]

I've been thinking about how the TrailTop parts might be used to build a similar hard cover for a military-style trailer, but because the military trailers have square corners, the rounded TrailTop corners wouldn't really work on the corners of a military cover.

So I was thinking I could make square corners. On the left are four of the rounded corners, and on the right I've drawn what a square corner would look like:



The square corners would mate with any of the other TrailTop pieces, and with four straight pieces would make a cover that perfectly fitted a military trailer. The first drawing is shown unpainted to illustrate the assembly of the parts.



And painted:



The same parts could also be used to build a chuck wagon/root-top tent platform:

[WoodSmith]

Good Lord man! I wish I could keep up with you!

An idea for the awning over the entrance to the tent: Go to the electrical tools section of your favorite hardware store and buy a heavy duty fish tape. These come with 50 to 100 feet of flexible springy steel tape. I am fairly sure that this is the same material that several manufacturers use to make the spring up tents, shelters and bags that are capable of being twisted into small discs of fabric for storage. Creating a pocket around the perimeter of the awning similar to a drawstring pocket and putting a length of this steel inside adds virtually no weight to the panel. The spingy-ness of the fish tape gently stretches the panel holding it in the general shape that you have predefined. Best of all, once removed via a zipper or velcro, the panel can be reduced in size very quickly just by a simple twist of the hands and then stowed in a pocket, or held closed with a loop of elastic or paracord.

Something similar to this:

As for the squared off corners of the military trailer, except for the fact that it would require a new mold (mould?) I think it would look better with chamfers everywhere rather than radii. Obviously the pieces that you just mocked up would need 90's to match the trailer, but the long pieces would match the utilitarian look of the military trailer and you could provide an attachment point for hinges, latches and racks that don't require curves.

Blarg, I realize I am failing to describe this even to myself. I'm going to try and draw something.

WoodSmith

[WoodSmith]

I hope this makes more sense.

I drew what I think the cross section looks like for your existing radius sections, then modified it with the chamfer look. So at least they can be compared.



I wonder if I can make it work in 3D?

WoodSmith

[jscherb]

...As for the squared off corners of the military trailer, except for the fact that it would require a new mold (mould?) I think it would look better with chamfers everywhere rather than radii....
WoodSmith

Here's what it looks like with chamfers everwhere:



Had I not already made the chamfered fiberglass cover in the photo above before I started the TrailTop project, I definitely would have done a TrailTop-based curved edge cover instead - I like the curved edge look. Also it's very efficient from a production point of view, if the TrailTop system ever gets to market, all that's needed to add support for the military trailers to the product line is the one square corner mold I described this morning. A company wouldn't have to cover the amortization of a complete set of new parts just for building military trailer covers, it's just one small mold. And the square corners would have other uses too, like this box for a $151.99 (on sale) Harbor Freight mini trailer...

[KCStudly]

I think the chamfer is better match visually, but understand the desire to minimize tooling (...and inventory, etc.). How about making the transition from hard 90 deg corner to curved top more of a blended transition, rather than a hard mitered line. In other words, start at the bottom and transition to a rolled corner radius at the top. Still just one separate corner mold, but a better blend between the two styles.

The mitered corner "edge" just seems to stand out too much (to me at least).

I must reiterate that if this sounds at all like criticism, it is not. All intended to be constructive in nature.

[jscherb]

I think the chamfer is better match visually, but understand the desire to minimize tooling (...and inventory, etc.). How about making the transition from hard 90 deg corner to curved top more of a blended transition, rather than a hard mitered line. In other words, start at the bottom and transition to a rolled corner radius at the top. Still just one separate corner mold, but a better blend between the two styles.

The mitered corner "edge" just seems to stand out too much (to me at least).

I must reiterate that if this sounds at all like criticism, it is not. All intended to be constructive in nature.

I don't take it as criticism, thanks for the input.

If it were shaped as you suggest, that would require new molds for the straight sections as well as the corners. My new corner design was an attempt to support hard covers for military trailers with only one new mold - the mold for the corner. The straight sections used with the new corner design would be the same ones that have been used all along during this project.

[KCStudly]

If it were shaped as you suggest, that would require new molds for the straight sections as well as the corners.

I must not have done a very good job of describing what I had intended; seems to me that it could all be done in that one corner piece.

I'll see if I can work something graphic up (tomorrow) to better explain what I am on about.

[WoodSmith]

Yeah, What KC said.

Actually he said what I was going to say better. I totally understand the tooling cost issue. My personal preference is that I like the way the chamfers follow the angular style of the military trailer. Just as I prefer the flat fenders over the half circle ones that you showed on there in another thread. But the radius style matches the corners of the Jeep tubs, and I think it looks better on the Trail-Top Tear-Drop as well. So to keep volume up and tooling cost and prices low, the chamfer style goes to the back burner. The single piece cover that you posted is almost exactly what I was thinking of. I think it looks perfect.

I think I see what KC is suggesting for the corner pieces that you are currently designing. It may be the perfection of rendered drawings that is catching us both up. The drawing makes the actual corner look almost like you took 2 pieces of straight, cut a 45 miter on them and magically fused them together, leaving a sharp corner at the joint. In general don't sharp corners lead to chips in gel coats and paints (and skin!)? If you put a 1/2 inch or so radius on the above magically fused miter, it would visually soften the corner and keep it more consistent with the rest of the elements in your design. I think there should be a radius that would allow softening the corner and still getting the 90 at the flange for mating with the trailer. It may be that an actual part would not have that "perfect" crease that the drawing shows though.

Glen
WoodSmith

[djb_rh]

Jeff, have you thought about modifying your safari top itself to pop-up, rather than adding a roof-top tent?


--Donnie

[jscherb]

Yeah, What KC said.

Actually he said what I was going to say better. I totally understand the tooling cost issue. My personal preference is that I like the way the chamfers follow the angular style of the military trailer. Just as I prefer the flat fenders over the half circle ones that you showed on there in another thread. But the radius style matches the corners of the Jeep tubs, and I think it looks better on the Trail-Top Tear-Drop as well. So to keep volume up and tooling cost and prices low, the chamfer style goes to the back burner. The single piece cover that you posted is almost exactly what I was thinking of. I think it looks perfect.

I think I see what KC is suggesting for the corner pieces that you are currently designing. It may be the perfection of rendered drawings that is catching us both up. The drawing makes the actual corner look almost like you took 2 pieces of straight, cut a 45 miter on them and magically fused them together, leaving a sharp corner at the joint. In general don't sharp corners lead to chips in gel coats and paints (and skin!)? If you put a 1/2 inch or so radius on the above magically fused miter, it would visually soften the corner and keep it more consistent with the rest of the elements in your design. I think there should be a radius that would allow softening the corner and still getting the 90 at the flange for mating with the trailer. It may be that an actual part would not have that "perfect" crease that the drawing shows though.

Glen
WoodSmith

Glen,
The corner wouldn't be "razor sharp" even though that's how the drawing makes it look. Probably about a 1/4" radius.

In general razor sharp edges and corners in fiberglass aren't a good idea, they're hard to mold - the fiberglass strands just don't want to bend into sharp corners (they're glass after all), so what often happens is you get air pockets between the gel coat and the first layer of fiberglass mat. The air pockets make the unsupported gel coat very prone to cracking, so some some amount of radius is always a good idea.

BTW the "single piece" cover is actually two pieces. I designed it that way for two reasons:

1. In halves, it's small enough to ship UPS Ground. A full 4x6 cover would have to ship truck freight, which would make the cover a lot more expensive for the buyer.

2. Being in two halves, the cover could be configured to open in the center if desired.

[jscherb]

Jeff, have you thought about modifying your safari top itself to pop-up, rather than adding a roof-top tent?

--Donnie

Yes, during the course of the LJ Safari Cab design project I considered several variations; the modular construction of the Safari Cab makes it possible to do things like that. I did some design drawings of an adaptation like the Ursa Minor, and also did some design drawings of a Flip-Pac type. I posted 3 or 4 design drawings during the design phase.

I'm now working on a JK version of the Safari Cab and I plan to reexamine the possibility in that project because people always seem to ask me about it.

[123jay]

Why can't you just cut your long piece at a 45 and bound it together? The only trouble you have is if the long piece was wavy. If you have no other profile to pick up in the corner. Would that save the use of a new mold ? As always impressed with your work.

[jscherb]

Why can't you just cut your long piece at a 45 and bound it together? The only trouble you have is if the long piece was wavy. If you have no other profile to pick up in the corner. Would that save the use of a new mold ? As always impressed with your work.

Yes you certainly could do that. But bonding a 45-degree corner together would be more difficult for the average person than using the tab system that the other TrailTop parts have. Here's a joint in progress, you can see how the tab has resin-soaked fiberglass on it in the first photo, and then it's clamped together in the second photo.





The parts don't have to be bonded with resin-soaked fiberglass, BTW, simple epoxy works fine, and for the Teardrop proof-of-concept I did all of the bonding with automotive body filler.

The TrailTop parts are designed to be very easy to assemble - I fear that making people cut their own angles and bond things together without the benefit of the tabs would frustrate too many people.

[jscherb]

I worked on a couple of details for the tilt-up today. When the top is down, the canvas can remain snapped to the cover and just jumbled down into the tub, but if you've got a lot of gear stowed in the tub it might be better to have a way to stow the canvas that works easily with the tub full.

Using a set of bungee cords and some screw eyes, the canvas easily stows up under the cover:



And when the cover is closed, the canvas doesn't take up any space below the cover. It hangs down slightly at first, but it'll compress to be completely within the cover if there's a load inside, so you can load the tub to the rim with gear and the cover with the stowed canvas will close just fine.