Build started//Sub 600 lbs / 2 months to build / aerodynamic

[YannG]

I spend a lot of time on this site but I find it difficult to find a foamie in the nano size that has been built. By nano size I would like to have the equivalent of the floor + 4 sheets of foam and a bit of wood for 2 door frames. I would think it would be below 300 lbs + the weight of the trailer. The bug out is something I could build in less than 2 months ( evenings and weekends) but I feel it would be like pulling a wall. I have seen the nano weekender ( wooden version) but not sure if those angles really help for wind resistance. A tiny teardrop I think it would be better in terms of aerodynamics but it is a more intense build for sure. If anyone can share experience and ideas. Driving a small 4 cylinder. Already bought some materials including the 4x8 trailer. Build start is imminent.Thx

[pchast]

Define what you mean by Nano size please.

[ghcoe]

I am working on a more rounded Bug Out right now. I prepped it for canvasing today and thought I would weigh the body before I canvased it. It came in at 91lbs. I use manufactured doors that come in around 30lbs and windows that come in around 10lbs. Harbor Freight trailer is 253lbs that comes in at 384lbs before exterior paint and canvas. My #2 build came in at 371 so my numbers might be off a bit on the doors and windows, but still should be well under 400lbs. If weight is of upmost importance you can purchase a Northern Tool aluminum trailer. They shave another 60lbs. off the trailer weight. Cost a bit more though.

Drag would depend on what you are driving. If the roof lines are close you probably would not notice much. The lower the tow vehicle is to the roof height of the trailer the more drag you will notice.

Good luck! George.

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[YannG]

Define what you mean by Nano size please.

Tiny tiny. 4 X 8 trailer. Walls to be 4 feet high max at the highest point.

[YannG]

[quote="ghcoe"]Good info. Much lighter than I thought. What type of construction you choose for your floor? Also, for the curve on the roof, did you use 2 sheets of thinner foam for ease of shaping or you did the kerfing?

[ghcoe]

Good info. Much lighter than I thought. What type of construction you choose for your floor? Also, for the curve on the roof, did you use 2 sheets of thinner foam for ease of shaping or you did the kerfing?

I use OSB for the floor. I do install what I call inner frame rails and floor spacers.

The inner frame rails disperse the floor loads along the wall better and hold the wall in position as well. It basically looks like floor board along the walls like you would see in a house.

The floor spacers raise the floor off the frame 3/4". This allows room for the drip edge and keeps the trailer frame and foamie body from rubbing together. Also, it avoids a moisture trap between the body and frame.

I did use two 1" foam panels to make the curves. Even with the slight curves there is still a lot of tension. This was a experiment to see if I could get away without kerfing to save time. Although I did get it to work I do plan to kerf the next build since it is a bit of work to keep the glue ups from coming apart.

I will do it like I did on #1. Kerf the bottom of the top sheet and the top of the bottom sheet. This way you don't have kerf lines to fill and smooth out.

[Socal Tom]

The impact of the shape on wind resistance is impacted significantly by the shape of the tow vehicle. My suggestion is to try and keep the roof line ( at least at the front), at or below the roof line of the TV, then you can slope up from there.

[YannG]

George, I hope you don't mind if I ask you a few questions along the way. I may borrow some ( many) of your ideas and techniques.

I think something with a rounded nose would significantly reduce drag. If I look at your pics, I would probably have to start the curve at the 2 feet mark on front wall. That would help my case a lot. Picking up more parts tonight. For the doors, I would love to build those myself. I know they might be a pain to build but it is one more challenge for me. Trying to keep weight down so I can add a few extras if it's possible. I would really like to carry a marine battery and that only is very heavy.

[Socal Tom]

George, I hope you don't mind if I ask you a few questions along the way. I may borrow some ( many) of your ideas and techniques.

I think something with a rounded nose would significantly reduce drag. If I look at your pics, I would probably have to start the curve at the 2 feet mark on front wall. That would help my case a lot. Picking up more parts tonight. For the doors, I would love to build those myself. I know they might be a pain to build but it is one more challenge for me. Trying to keep weight down so I can add a few extras if it's possible. I would really like to carry a marine battery and that only is very heavy.

What do you plan to power with the battery? With the size/weight you are describing, I think you could probably get away with something lighter than a marine battery. I carry an 85 amp hour marine battery, with a 12v refrigerator, and without solar it would usually go a weekend without requiring a recharge ( meaning staying above 50%), so 40 amp hours was really all I used. Unless you have some big power drain planned, a 35 amp hour lithium would work better with your goals.
Tom

a couple of these won't cost much more than a marine battery https://www.amazon.com/LiFePO4-Battery- ... 60&sr=8-18

[ghcoe]

George, I hope you don't mind if I ask you a few questions along the way. I may borrow some ( many) of your ideas and techniques.

I think something with a rounded nose would significantly reduce drag. If I look at your pics, I would probably have to start the curve at the 2 feet mark on front wall. That would help my case a lot. Picking up more parts tonight. For the doors, I would love to build those myself. I know they might be a pain to build but it is one more challenge for me. Trying to keep weight down so I can add a few extras if it's possible. I would really like to carry a marine battery and that only is very heavy.

I did a 2 foot radius on my #1 Build. You will need to kerf on that sharp of a radius. You can read about how I did it starting near the bottom of this page viewtopic.php?f=55&t=54099&start=90 . You might want to read through the whole thread to get some ideas on other build techniques.

I built the doors on #1. They work, but for the time and effort I spent trying to make them work, and not the greatest at that, it was nearly a bust compared to a manufactured door. Don't think of it as just a door though, it does have a window so you are killing two birds with one stone.

[YannG]

The impact of the shape on wind resistance is impacted significantly by the shape of the tow vehicle. My suggestion is to try and keep the roof line ( at least at the front), at or below the roof line of the TV, then you can slope up from there.

It's a golf. The station wagon. Version . Still fairly low. If I substract the height of roof line of tv to the trailer frame, it gives a big 30 inch. So I guess anything lower than 30 inch at the front would help. Design design

[YannG]

[quote="Socal Tom"][quote="YannG"] Basically just a charging station for phones, speakers, small usb fan, lights. I don't plan at making crazy electrical work. Will carry an extension cord, a 12v charger and a powerbar in the event that we have access to 110v.

So your suggestion is very valid. Never thought of those. I still live in 1990 I guess. The only thing I could think of was a huge marine battery.

[ghcoe]

Basically just a charging station for phones, speakers, small usb fan, lights. I don't plan at making crazy electrical work. .

Go with a Jackery, or similar power station, all in one and portable.
https://www.amazon.com/Jackery-Portable ... lp13n_t4im

[YannG]

That design George could very well work for me using the input of others as well. I will keep you updated. I have to finish my deck and I should be right at it after.

[skyl4rk]

Lowering the rear end of the trailer body will have a greater effect on aerodynamics than rounding the front end.