Questions about a miniature fiberglass td

[levsmith]

Hey everyone,
I am a motorcycle guy and just got me a big black lab. He loves going for rides in the pickup but I like going for rides on the motorcycle. So I have been thinking about and working on a design for a miniature teardrop that I can pull behind the motorcycle to take him along and also for a place to crash at night should I go on any longer trips. My only problem is that my motorcycle is only a 650cc so it doesn't have the power to pull a whole lot comfortably. I am guessing 300lbs would be about as much as i would want to pull and being the dog is 100lbs, that leaves me with the challenge of building something that weighs no more than 200lbs. Basically all i am wanting is an enclosed shell, no kitchen or anything like that. What I have been thinking about is building with fiberglass rather than wood. I've never used it before but am a quick learner once i see a few youtube videos and start going hands on.

One part I am stuck on is whether to go frameless or not. I have read a few threads on here about torsions boxes but havent seen a whole lot. Just going by shipping weight on northern tools website, the coupler, rubber torsion suspension, hubs, wheels and tires are right at 100lbs. So I have about 100 lbs to work with on the body/frame. The size I am thinking about is 36"wide, 30"tall and the flat part of the floor at 60"long.

Does anybody know of any builds like this? Any opinions? Am I absolutely nuts thinking I can build something less than 200lbs?

Levi

[KCStudly]

How tall are you? You will want at least 6 to 8 inches more length than you are tall, especially with only 3 ft wide.

There was a very light weight monocoque build on here using some pretty sophisticated composites, but might not be the best choice for someone with zero experience.

Here it is: viewtopic.php?f=50&t=44293

[M C Toyer]

I would think a conventional trailer like Northern Tool or Harbor Freight would be overkill for your purposes.

Perhaps something using bicycle wheels or modifying one of the bicycle pilled child carriers would suffice. There are a few in the Hall of Fame and if you go to their build threads links to many other designs and construction methods.

This is but one example and you might be able to use the collapsible sun, rain and wind covers from a child carrier attached to the roof for the lab to see and breathe but not be exposed directly to the elements.

[rowerwet]

using fiberglass alone would be heavier than wood. foam would be your best bet for the weight target you have, just make it very streamlined for towing with a small bike motor.
make sure the tires you use can take the side loads of cornering, motorcycle and bicycle tires don't really see much side loading as the frame is leaning into a corner, however the trailer will keep the tire vertical and put all of the load on the spokes in a way spoked tires aren't made for.

[TPMcGinty]

Here is one that weighs 200 lbs:

http://www.kompactkamptrailers.com/#!pet-trailer/c1dt3

[levsmith]

How tall are you? You will want at least 6 to 8 inches more length than you are tall, especially with only 3 ft wide.

There was a very light weight monocoque build on here using some pretty sophisticated composites, but might not be the best choice for someone with zero experience.

Here it is: viewtopic.php?f=50&t=44293

I am right at 6ft. As you can see from the pictures, my design uses almost a half circle on both ends with a total length of about 80 inches, so once I am raised off of the floor 3 or 4 inches, I think i should have enough length. I actually sleep curled up on my side about 90% of the time anyways. The 3ft is pretty narrow but I am trying to keep the wind resistance as low as possible. The hardbags on my motorcycle are the widest part of my bike and they are right around 38-40" wide. I may be able to widen the trailer a few inches, depending on how much weight it adds. It will be just me and the dog in it.

Thanks for the link to that build. I've heard people talk about it but never could find it. That is quite the build and probably above my skill level.

[levsmith]

using fiberglass alone would be heavier than wood. foam would be your best bet for the weight target you have, just make it very streamlined for towing with a small bike motor.
make sure the tires you use can take the side loads of cornering, motorcycle and bicycle tires don't really see much side loading as the frame is leaning into a corner, however the trailer will keep the tire vertical and put all of the load on the spokes in a way spoked tires aren't made for.

Thanks for your reply. That is one question I had. Pro engineer calculated that design at 65lbs but that was at just a hair less than 1/8" thick. Being I have no experience wih fiberglass, I wasnt sure how thick it needed to be. I will look into foam a little more. I just wasnt sure how to make a tight curve with foam other than cutting v-nothes in it so that it would bend.

[levsmith]

Here is one that weighs 200 lbs:

http://www.kompactkamptrailers.com/#!pet-trailer/c1dt3

Thanks TPMnGinty. I've seen that one before but didnt care too much for the price. I also wanted something I could sleep in should the need arise

[TPMcGinty]

Here is one that weighs 200 lbs:

http://www.kompactkamptrailers.com/#!pet-trailer/c1dt3

Thanks TPMnGinty. I've seen that one before but didnt care too much for the price. I also wanted something I could sleep in should the need arise

200 lbs and big enough for your to sleep in? You will probably have to build a foamy.

[rowerwet]

you mentioned your dog riding in the trailer, my first thought was how dogs love the wind in their face, the next one I had was of an old car and driver or road and track short article about how one of the editors had a hole cut in the trunk lid, on a caddy IIRC. the hole was to allow his dog to ride in the trunk and still stick their head out when they wanted to. The idea wasn't new to him, he was copying one added to the trunk of of a Mercedes by the founder of the company IIRC. the hole was large enough for the dog to stick their head out comfortably but not get their shoulders through. I had a rotating lid to cover the hole for rain/snow.
The editors dog loved it, and the editor loved having no muddy prints on the leather seats.

[KCStudly]

I would be worried about the dog getting debris in his eyes. Does he wear goggles?