Bolt-together fiberglass Jeep-tub trailer kit

[jscherb]

I've been thinking ahead to various options that might be interesting for these kits. I'd like to hear any input you have on these or any other options you'd like to see.

There are a few different tub/tailgate options that could be done:

The top tub in the drawing is the standard tub. The middle one is the standard width but has a 4' tailgate opening. The bottom one has 48" wide end panels (the standard end panels are about 59" wide), so it sits between the fenders of many trailers, including most of the Harbor Freight trailers, and the Lowes trailer I posted a while back. I've drawn it with the small HF tires; I think the narrow tub would look ok with the small tires that come with the HF frame.

A few other option ideas:

1. Stake pockets. Optional fiberglass molded parts that bond to the inside of the tub side. Stakes could be used to add higher sides to the tub made out of wood, or perhaps supports an "overhead frame" like some off-road trailers have.

2. Different width inner fenders, so people could choose the optimum axle track width for their application, and have inner fenders which didn't waste any space inside the tub by being too large for the track width chosen. Example, a standard Wrangler track width would require inner fenders to protrude about 9" into the tub from each side wall (resulting in abour 42" between the inner fenders; a wider track width could use 5 1/2" inner fenders allowing 49" between them. The mold master is already made for these, just have to make molds for different widths off that master. Or, tiny innner fenders could be done for people who plan to keep the original HF tires/wheels (would anyone keep those tiny tires?)

3, 4. (Never mind, edited these out and forgot to renumber)

5. Hard tonneau cover. For those who want the security of a locking hard cover, this also would be capable of supporting a roof rack and carry loads.

6. Tent platform. Derived from the hard tonneau, this would flip open, doubling the top area of the trailer, and serve as a platform for raising a tent. Inexpensive "ground tents" would be supported, so you could turn this into a tent trailer with this option and a $50 entry-level tent.

7. Side-swinging fiberglass tailgate. Probably for the guys who would put a tent on top of the trailer, a side-swing tailgate may allow easier access to the cargo area than a drop-down.

8. Nerf bars. I posted about them the other day.

9. The "lego" storage pod I posted yesterday.

Now that the base trailer is in the final details and finishing stage, it's time to start thinking about any other features/options I might build for it. Any other options you guys would want?

 

[Espo78]

With the tub being as short as it is, I don't see the point of the wider tailgate since the wheel wells take up so much side storage space already. I actually the narrower tub model you posted (#3) as the "super economical trailer" as it would not require larger wheels/tires, bumper, etc and seems like it would be easier to build. Maybe they are all easy though from what it looks like. It also doesn't appear to have that much less storage space because there are no wheel wells protruding inside. However for a longer trailer I would like the full width size.

 

[jscherb]

With the tub being as short as it is, I don't see the point of the wider tailgate since the wheel wells take up so much side storage space already.

Agreed, for the 4' proof-of-concept trailer, a wider tailgate isn't useful. But the molds can make side panels up to 8' long, so for a longer trailer, a wider tailgate could be very useful.

I actually the narrower tub model you posted (#3) as the "super economical trailer" as it would not require larger wheels/tires, bumper, etc and seems like it would be easier to build. Maybe they are all easy though from what it looks like.

They're all simple to build, they basically bolt together. But the narrower tub could fit on the smaller HF trailers and would work fine with the little HF tires. It would also be less expensive, because there are two fewer fiberglass parts - no inner fenders. The HF metal fenders would be used.

It also doesn't appear to have that much less storage space because there are no wheel wells protruding inside. However for a longer trailer I would like the full width size.

Agreed.

 

[jscherb]

A couple of people have asked me about the strength of the tub and whether it would need to be reinforced in order to support a tent platform. In the photo below, all of the weight of the 225-pound gorilla is sitting on the edge of the tub; and all of that weight is concentrated on only maybe 18" of the top edge of the tub There's no flex or movement of the tub whatsoever.

In addition to the 225-pound gorilla test, I've calculated that for the 4' proof-of-concept trailer, a 500-pound tent load resting on the top edge of the tub (roughly 2x200 lb. people plus 100 lbs. of tent and platform), the load on the floor flange would be less than 4 pounds per inch, which is well within the strength of that flange. The tub also has plenty of torsional strength due to the inner fenders, so it won't twist under that weight either. So no additional bracing or framework is necessary to support a tent platform + tent + 2 people on the top edge of the tub.

The tub is a lot stronger and more rigid than you might think. No worries at all about strength for the tent platform.

 

[Fresno]

I need a box, storage module and roof top for the current Light Tactical Flatbed Trailer (Silver Eagle). 86" long x 55.8" wide. Can you help me on this?

 

[jscherb]

I need a box, storage module and roof top for the current Light Tactical Flatbed Trailer (Silver Eagle). 86" long x 55.8" wide. Can you help me on this?

I'm not familiar with those trailers, but these tubs are the same width as the CJ/YJ/TJ tubs - 59". If the tub must fit within a 55.8" dimension, then these are too wide.

 

[wjeeper]

I gotta say that your design process to the actual implimation of ideas is simply awe inspiring! I have played with fiberglass work a bit, mostly on speaker boxes and my kayak, with varying degrees of ho-humm results.

I also seem to remember that 4 Wheel Drive Hardware offered a similar one piece tub 10-15 years ago and that I oogled over the idea then!

I have got to say that this picture shows the mark of a craftsman:

Not only does it survive the "gorilla" test, but the glass looks excellent! I would care to venture it would survive the "godzilla" test also. A good smooth gellcoat like you have produced takes more mold prep work than I have patience for! I agree with others that a carbon fiber/ epoxy resin/ aluminum version would be neat from an engineering prospective, but it would kill the affordability factor by pricing itself into the realm of unobtainum.

If you ever decide to have a BYOFAR (Bring your own fiberglass and resin) party send me a PM! I would seriously consider driving from Ut-Ny for such a proposition. Even if the cost of fuel would far exceed the cost of a tub, learning the tips and tricks of fiberglass from a master would be well worth it!

 

[wjeeper]

Great build! I'm doing the same thing but in metal.

Not to hijack a thread but what ever happened with this tub? I was following it on pirate several years ago on irate4x4 (2009 or 2010) and if memory serves me not much happened after the two tubs were welded together.........update, perhaps via PM so not to disturb this thread?

 

[grimbo]

Really like the pod idea, great potential for a whole range of applications.

 

[jscherb]

I'm working on a few of the design details of the flip-open tent platform.

The idea is that the platform would support any "ground tent" that would fit in the area provided by the platform, which is roughly 5x8 (or 4x10, but more on that in a second). There would be tie-down points on the platform that would serve the function that tent stakes would when the tent was pitched on the ground.

An entry level tent for this platform could be something like this Coleman 5x7 tent, which sells for less than $50:

That's just the least expensive one I found while doing a quick search, I'm sure there are all ranges of cost, features and quality to pick from, but I want to use an entry-level budget tent as a design point.

The question I'm trying to decide is which direction does the tent platform open? Using the 4' proof-of-concept trailer as the minimum size design point, if the platform opens to the front or to the rear, it would be 5' wide and open to 8' long. If it opens to the side, it would be 4' wide and 10' long. I think the 4' dimension might limit the choice of tents, seems to me that most 2-person tents are closer to 5' wide than to 4' (but tell me if I'm wrong on that).

If the platform opened to the front, then the open part could be supported on the tongue, making the trailer self-contained in the field. If it opened to the back or the side, legs would probably be needed to reach the ground, although in the side-open case it might be possible to make braces for the open platform that attached to the frame. Opening to the back limits access in through the tailgate; opening to the front limits access to any storage on the tongue. Opening to the side doesn't have any access issues to the tub but the 4' dimension may limit the choices of tent too much.

I'd like to hear your views on this design question.

 

[jscherb]

And here are a few photo-concepts showing the trailer with a side-opening tent platform and a large ground tent.

Front-opening tent platform:

Side opening:

These are just very rough photo-hacks to give an idea of how a tent platform might look.

 

[jscherb]

Perhaps some people would prefer a dedicated tent designed for trailer-top usage rather than a ground tent pitched on top of the tent platform, so here's another photo-concept - it's a tent that's designed for DIY trailer-top usage.

It looks like this one could be easily adapted to fit on this trailer tub.

This one also has an optional "changing room", but I didn't show that on the photo/mockup above:

 

[jscherb]

I gotta say that your design process to the actual implimation of ideas is simply awe inspiring!

Thanks!

I have got to say that this picture shows the mark of a craftsman:
<<photo omitted >>
Not only does it survive the "gorilla" test, but the glass looks excellent! I would care to venture it would survive the "godzilla" test also.

Besides using this tub for trailers like the one I've been showing, the other reason I built this tub kit was for building "Budget Brute" pickups, so I wanted to be sure it was strong enough to also serve as a pickup bed. In a 6' length, one of these tub kits would work great for a pickup conversion, and I've got no reservations about its strength for that application as well. It's really quite a bit stronger than you might imagine.

A good smooth gellcoat like you have produced takes more mold prep work than I have patience for!

Gelcoat isn't really very hard to do, and the resulting finish you get is pretty much a function of the smoothness of the mold you've made, which of course is a function of the smoothness of the original master you made for the mold. So if you take your time and do a good job smoothing/finishing/buffing/polishing your master part before you make the mold, that will translate to the final parts. I guess that does take a little patience, but it isn't rocket science, just decent bodywork.

Also you really need a gelcoat gun to spray the gelcoat on the mold, you might get a good finish using a brush, but it's a lot harder than spraying with a gelcoat gun. Gelcoat guns are less than $150, they're really worth the investment.

If you ever decide to have a BYOFAR (Bring your own fiberglass and resin) party send me a PM! I would seriously consider driving from Ut-Ny for such a proposition. Even if the cost of fuel would far exceed the cost of a tub, learning the tips and tricks of fiberglass from a master would be well worth it!

 

[Espo78]

One thing to consider is when the tent is pitched on top of the trailer, how stable it will be if the trailer is not attached to a vehicle. Too much weight on the back would lift the tongue causing a catastrophe. That is why I think having the floor flip forwards or to the side would be the best way to design it. However if you can somehow eliminate the possibility of the tongue lifting, opening to the rear would allow access to the front storage compartment, and if you utilized a tailgate opening in the front of the trailer you could also access the inside of the trailer that way as well.

 

[jscherb]

One thing to consider is when the tent is pitched on top of the trailer, how stable it will be if the trailer is not attached to a vehicle. Too much weight on the back would lift the tongue causing a catastrophe. That is why I think having the floor flip forwards or to the side would be the best way to design it. However if you can somehow eliminate the possibility of the tongue lifting, opening to the rear would allow access to the front storage compartment, and if you utilized a tailgate opening in the front of the trailer you could also access the inside of the trailer that way as well.

Agreed, some form of stabilization could be necessary, depending on which way the platform opens up. One solution is to use trailer stabilization jacks like those pictured below, I found these for about $40 per pair on eBay:

Another idea could be to use the rear receiver that I've put on this frame - should be pretty simple to make a rear support that slips into the receiver and prevents the tongue from lifting.