Another new design

[BobR]

"blue portable holding tanks with wheels"

Andy,

The holding tank is for "grey water only" not "black water" since I will use a self-contained porta-pot, so I don't believe that is an issue. Most parks and campgrounds do not allow draining or dumping grey water on the ground so the portable tank is an ideal solution.

Thanks and Happy New Year.

[angib]

Bob,

As usual, I need to draw out an idea to find out what I think of it. So here is my version: lemondrop.pdf

Before you go much further, I think you need to start including 'reality items' like real wall thicknesses and transfering the profile shape onto the plan view. Doing this has shown me that:
- the shower tray, where you've shown it, would be sticking out about 7" forward of the bodywork, due to the front body curve;
- by the time the wall thicknesses are added, I don't think there's room to have the sequence of shower tray, then standing room, then portapotty in the bathroom, so I'd add a fold-down cover over the (recesed) shower tray and use that as the standing room;
- I've added a squeeze clearance line around the table edge (I use 12" - if you're thin, you can use less) showing where the bathroom wall must stop;
- The galley slide-out you've shown bumps the dinette waaay into the air and there is only headroom over the side seats and not at the back (headroom clearance line shown at 34" above uncompressed cushion).

You wanted a frame design and I think what I've drawn would work, unless you make the trailer body really heavy. The weight of the steel only in the chassis shown is 255lb.

I've put the axle where it gives about 10% hitch weight when the galley has got about 200lb weight, but the axle position might need to be revised once you've finalised water tank positions and other major weights.

Andrew

[mikeschn]

Andrew,

I like the floor plan of the lemon drop. It's very similar to the information I sent you in an email. I don't need a WC though, so the counter will go all the way to the end, like in the Lil Guy. The shower is perfect! I'm not sure I can see around the trailer in my Passat. I might have to rotate the bed 90* and make the TTT longer. I am not crazy about the Lemon Drop profile.

Mike...

[BobR]

Bob,

As usual, I need to draw out an idea to find out what I think of it. So here is my version: lemondrop.pdf

Andrew,

You are one smart fellow...thanks for your input and design re-work as well as the chassis design. Well done. Your points are well taken and make perfect sense to me.

Happy New Year

[Grant]

Bob asks:

"...Am I ever going to see that top secret tear we discussed at SCTT back in 2001?"

If it's the one I'm thinking about (the "slightly" modified Modernistic/Cub design), then yes ... someday ... maybe ... ;-} ;-} ...! I've got the chassis done, but that's been that way for over 3 years ...
T&M, Bob ... that's all I need!

Andrew -

As always, nice re-work! And as usual, very thoughtful. It looks as if you are figuring a total outside wall thickness (one wall) of something 'round 2"? May I suggest that more room can be gained inside (or a narrower overall width, if you prefer) by going with a 1" wall thickness? On a trailer this size, more-than-adaquate strength can be had by starting with 3/4" framing material (plywood, even), and if you are worried about insulation/R-value, simply step up to a better/higher-R-rated grade foam. You can use this same 1" wall thickness for the front & back walls, but I'd stick with the 1-1/2" framing (or slightly more) for the roof/ceiling.

Thanks, BTW, for all you contribute to this 'Board!

One thing more on this LemonDrop (and other similar) design - why not give a little thought towards "finishing out" the bottom part of the profile by adding a "skirt" below the floor-line that hides the chassis? It wouldn't affect ground clearance, and it would certainly minimize the box-on-a-frame appearance that seems to becoming more-and-more common. ALL teardrop and tiny trailer mfgs. included this feature starting right after WWII, and some well before. Just one of my many observations, FWIW.

CHEERS!, Y'all!

Grant

[mikeschn]

"...Am I ever going to see that top secret tear we discussed at SCTT back in 2001?"

If it's the one I'm thinking about (the "slightly" modified Modernistic/Cub design), then yes ... someday ... maybe ... ;-} ;-} ...! I've got the chassis done, but that's been that way for over 3 years ...
T&M, Bob ... that's all I need!

Grant

Grant,

Is that by chance, the one that I started modeling?

Mike...

[Grant]

"Is that by chance, the one that I started modeling?"

Nope!

This one is so secret that I have to think real hard to remember where I hid the drawings ... ;-} ;-} ...! I have stacks of 'em, I tell ya! A few I squirrel away in the "Someday-Gotta-Do-THIS-One" file! It'll turn up, though ...

[Joseph]

Hey Bob,

Put the plastic tub in and use a bilge pump to send the water out to a portable holding tank

Bilge pump? Portable holding tank? The reason I'd use a plastic tub is so that I can pick it up and dump it out - K.I.S.S.

Joseph

[Guy]

Dear Andrew,

You are the Lord of Streamline, but have you gone over to the Darkside?

So much rectangular tubing with angle supports, on top of a torsion axle.

I did not look like the lemondrop with the dexter would be subjected to that much twist,even building to yankee overengineering. hehe. You have also lowered the chassis with 0 deg so why the extra support. I know I am probably missing something so could you please explain.

[angib]

You are the Lord of Streamline, but have you gone over to the Darkside?

Neah, that's called "respecting another man's beliefs (however misguided)" as it follows Bob's original design as closely as possible....

Sadly the Darkside won in a recent UK census - there was a campaign to get Star Wars fans to put 'Jedi Knight' as their religious affiliation, as the rule was that if more than 10,000 (IIRC) people declare a religion, the government recognises it. The government changed the rules retrospectively! See what happens when you live in the land of the unfree and the timid?

I did not look like the lemondrop with the dexter would be subjected to that much twist,even building to yankee overengineering. hehe.

Yeah, I may have overdone the transverses there - they were all 3"x1" initially, but the weight saving wasn't great. Also is looks like Bob's going to pile stuff into the trailer, so overdesign might be wise.

As fas as I am aware, the only transverse that a trailer chassis needs is the one in the axle - all the others are there to hold up the body and floor.

The angle 'supports' in the tongue are there to hold up propane tanks, batteries, spare wheels, etc - they're not needed for the rest of the chassis

You have also lowered the chassis with 0 deg so why the extra support. I know I am probably missing something so could you please explain.

I have looked at Dexter data and decided that I should draw trailers with the axles in their static loaded position, rather than their unloaded position. From their spec sheets, Dexter's rotate 22.5deg from unloaded to static load and a further 10deg to full bump (they say 'shock load'). So that's a 22.5deg (unloaded) down angle axle at its static load angle of 0deg.

Andrew

[Grant]

"From their spec sheets, Dexter's rotate 22.5deg from unloaded to static load and a further 10deg to full bump (they say 'shock load')."

Andrew!

That's the trouble with spec sheets - they don't accurately reflect their real life products (at least, in this case!). I've been using Dexter TorFlex axles exclusively for some 10-11 years, now, and I've NEVER experienced a 22.5deg rotation from unload-to-static. 5deg maybe. 10deg full bump is about right. As an example, when I order a 0deg start-angle 1,000# axle and drop a 750# teardrop-and-chassis on it, rotation to static is never more than a degree-or-so off 0. As I load it up to the 1,000# rating, I might get another deg or so. That's been my experience, right up into the 3,500# rated axles, FWIW.

CHEERS!

Grant

[angib]

That's the trouble with spec sheets - they don't accurately reflect their real life products (at least, in this case!).

Thanks for the info, Grant. As ever, booklearning ain't no substitute for experience.

My experience of UK (separate left and right) rubber torsion units is that they certainly have a very 'rising rate' - what movement there is, is on the intial loading, which fits the Dexter data. However German Al-Ko units which have a basically triangular housing seem to be much more linear with some useful suspension movement left beyond the static loaded position.

Andrew

[Arne]

Grant, have you ever had to have an axle 'repacked' due to the rubber rods degrading?