Ultralight Design?

[mikeschn]

I'm thinking about doing an ultra light weight design.

What comes to mind is the Modernistic, but in wood instead of aluminum. A little bit like Andrews New Light Weight Cub, but even lighter.

What do you think? Is there any need for an ultra light weight?

Would you like to see the framing on the outside like a slumber coach, or on the inside like a Modernistic?

What else would you like to see in an Ultralight? (or not see as the case might be...)

No a/c wiring.
No lights?
No propane plumbing
No cabinets (the Modernistic had a single shelf on the inside)
No trailer frame

Any thing else? Your thoughts? A different shape than the Modernistic?

Mike...

P.S. My inspiration... the 1/4 Nelson...

 

[bledsoe3]

Mike, I think there would be a lot of interest in a light weight tear. Many have posted just that. I think A/C only (no battery). Just a power strip from shore power, no propane plumbing and no cabinets. Maybe a shelf in the cabin and a countertop in the galley.

 

[PaulC]

Okay Mike, Time to stretch the friendship here. How about a lightweight offroad TD. I know that a lot of people think heavy with offroad stuff but with the current crop of light weight 4WD's on the market there could be people interested in it.
I like the idea of keeping it basic eg no full on galley and maybe only shelves inside.
But I would only have 12V (Iknow Bledsoe, adding weight) not a/c power.
Cheers
Paul

 

[Chip-TNT]

Mike,, when you say ultra-light, what weight range are you shooting for,,
just my ideas on the subject but definately no a/c, small 12v/120 converter for shore power and 120v power strip, basic galley with minimal shelves/cabnets, one door to cabin,, wall framed with 1/8" interior ply, insulated and .032 alum for exterior, and if ya going ultra then lighten everything sort of like the cowper did,, use some framing but again minimal,,

chipper

 

[Loader-TNT]

I would think ther eis acall for it, we have seen many people asking about smaller cars pulling a TD. My thoughts are:

12VDC w/inverter - maybe 1 cabin light, 1 galley light, 1 12vdc outlet in cabin and 1 in galley

No A/C power (extension cord/power strip)

Basic galley, no cabinets, only shelfs, 1 upper, 1 lower, open storage under

No inside cabinets, just a shelf

No wall insulation, just 3/4 ply walls (might be able to cut to 1/2), sealed/painted and a 3/4 floor

If insulation is a must, then 1/8 walls (in and out) over 3/4 framing with the insualtion

Roof - 1/8 in and out, with internal insualtion (helps strengthen)

Like Chip said, 1 door to cabin

No propane plumbing

Use the light-weight HF folding trailer as frame for easy assembly (if to put out as instruction) or build a basic lightweight A-frame. You know what I mean, 2 sides which form a "V", with the axle being the cross member of the "A".

 

[mikeschn]

Okay, here's what I am thinking.

This is a shortened up version of the Modernistic. It'll get pine framing on the outside. The walls are 1/4" moisture resistant luan.

There's room in the galley for a stove. A little bit, (not much) storage under the counter.

I'm thinking a motorcycle battery under the counter. A single light in the galley, and a single light in the cabin.

1 shelf in the cabin.

My goal is to come in under 500#, with a tongue weight of 75#.

Oh yes, 48" wide...

Any more thoughts...?

Mike...

P.S. Oh yes, no frame. We'll bolt the axle to the floor...

 

[toypusher]

Mike,

You could make the walls with 1/8" plywood inside and out with 1/4" foil-bubble-foil insulation. Of course you would need 1/4" framing between the skins.

 

[Chip-TNT]

Mike, what you have sketched is not too far from the new trailer,, the shape is somewhat reversed though,, meaning I have more slope in the front than the rear, this lets me use the area under the counter for storage and converter,, counter has a 2' wide lift up panel to access the under storage area,, a simple cabnet that can be accessed from cabin and galley,, I got to get it weighed but I am guessing 600 lbs empty and tongue weight is about 40 lbs,,, I got to load stuff in the cabin to give enough tongue weight for better pulling,,

chipper

 

[bg-TNT]

I'm guessing that you're looking towards wood framing not steel.

I've got an idea in my head that theorhetically would create a 600lb or less 5x8 tear, using an unibody structure. Just an idea I had, Maybe I'll get to play with it more this year.

 

[critter-TNT]

hey mike,
maybee alum frame? how bout something like airplane... painted cloth over wood?

 

[vairman-TNT]

Mike, Let me ask you this.... How light would be to light? Looking at the side profile surface area ( and let me state i'm not an engineer) but if you were to go to light (less that 500lbs) and you were setup on a campsite and there was a wind gust of lets say 30-40mph, would you end up having to upright you tear or maybe shed some?? ... I have tried to carry sheets of plywood on a breezy day and it's no fun.. Just wondering because down here 30-40mph gusts are fairly common...

Just my 2cents...


Greg

 

[Mitheral]

Mike, Let me ask you this.... How light would be to light? Looking at the side profile surface area ( and let me state i'm not an engineer) but if you were to go to light (less that 500lbs) and you were setup on a campsite and there was a wind gust of lets say 30-40mph, would you end up having to upright you tear or maybe shed some?? ... I have tried to carry sheets of plywood on a breezy day and it's no fun.. Just wondering because down here 30-40mph gusts are fairly common...

I'd bet your basic tear is going to be pretty hard to tip over from the side. A 4'W 4'H tear is going to be about as wide as it is tall or wider than it is tall. And the mass is concentrated towards the bottom where the floor /framing /axle is located and where gear is stored. A 5' wide tear is even better.

Front to back might be a different story.

 

[raru1999]

i really like your thinking!!

since i have never really towed anything before i've been trying to get learnt in the ways of towing capacity while sketching ideas for a trailer. it seems that i need to be in the sub 500lb range for my square, which is doable, but will only be the bare minimum which i'm sure the wifey won't be keen on... i'm interested to learn from this thread.

 

[alaska teardrop]

Mike - Really cool idea! And I really like the shape and the KISS concept. Since you asks for thoughts, my first two: You could gain more galley by moving the wall forward about a foot.

• I had originally designed a tail compartment but decided that it would difficult to access. Therefore, just a shelf.
  

Keep up the fine work Fred

 

[angib]

My thoughts:

Rounding the bottom edges at the front and back does lose quite a bit of space which, even in an ultralight, is still valuable. Also if you're not using a metal frame, having the front panel reach the bottom somewhere near the vertical (say, as upright as 45deg) makes it a better front support for the tongue.

If you're gonna say the Superleggera doesn't do this, I'd say: Yup, I now think it's wrong!

So my version would look something like this:

The extra 5" of galley space isn't all due to the shape - I've assumed I can cut the mattress foam at an angle as that gains me another 3" while still having a 75" long top surface of the mattress.

It is the vertical sides and ends of a teardrop body that provide the vertical strength - the floor is just a trampoline strung between the sides and ends. I have an idea for a wooden tongue too, though frankly I don't think it's worth the effort - but I'll try to work on that tomorrow jsut to start a decent argument!

Andrew

 

[Jiminsav]

Gee..i'm doing a moderistic, full size, with minimal frame for axles and tongue, 1/4 inch luan on the inside, framed and covered with cloth and paint..i wonder if it will be light?..

 

[mikeschn]

Hey Andrew,

I'm impressed... you gained me some extra space without extra weight... I like the way you think...

Okay, let's talk floorboards...

I'm thinking either a torsion box (aka a hollow core door) or a rigid panel covered only on the top with a couple layers of 1/4" luan... 1/2" baltic birch plywood would be a better choice, I'm sure...

But more importantly, each of the edges is a 2x? piece of oak so that I've got some material to bolt the axle to...

So if each side is a 2x3 piece of oak, with a piece of 1/2" plywood on top... then the bolt has to go thru 2" of wood (1 1/2" of oak and 1/2" of baltic birch). That should hold up, don't you think?

Now the tongue, that's another question indeed... at first thought, I'm thinking a straight tongue, that we can bolt a couple onto... This tongue can be 2x2 or 2x3... your choice... but what do we fasten it to? We could run a bolt thru the floor and thru the tongue, every foot or so. The floor would have to disintegrate for the tongue to come loose.

Your thoughts...

Mike...

 

[Jiminsav]

if you can find a piece of 4x4 live oak, that would make a groovy tongue..live oak was used to build clipper ships before steam came about, and clipper ships could take quite a beating..you could even drill a 2 inch hole 3 inches back from the front up from the bottom, and drill ¾ holes through the sides for dowl pins so the ball don't pop up..somebody draw that up and i'll see if it's what i imagine

 

[Jiminsav]

here's something i drew with Paint..I know..it sucks, but it conveys the idea

 

[toypusher]

Mike,

Steel tongue with a plate welded to the end that attaches to the bottom of the tear. Say about 18" wide by 24" or 36" long to distrubute the stress when you bolt it to the floor assembly. Or just make the tongue an 'A' frame type that connects at the axle stubs.