levitating tent

Posted by: arfa

levitating tent - 04/17/21 09:25 PM

I am finalising the design of my latest tent. It will be a prototype which, if all goes well, I will rework using dyneema.

So, I have a theory about raising (levitating smile the tent. The design (and calculations) are based on all wall edges coming to the ground - not allowing for catenary curves. My theory is... if I design for, say 900mm poles (at the head end), then put in 950 poles there will be a 50mm air circulation gap all around. A single wall design needs air movement so I could even go to 1000mm - with 100mm gap.
A rough sketch...


The logic seems sound but I wonder if you all have any comments on this?

Theory plan two: I am keeping wall to floor tub distances to a minimum so will have an extra grommet (on a strap) so that I can alter the angle of the pole to drop it back down to zero(ish) ground clearance when there is wind and wet.
>> a kind of lowrider hydraulic jackup system

I would appreciate any comments on the theory. thx
Posted by: BZH

Re: levitating tent - 04/19/21 09:21 AM

Tarptents maintain clearance at the bottom tent like that and then use a bath tub floor to prevent water splash back. I agree with you (and I think the industry does too) air flow is critical in a single-wall tent design (I think it is pretty critical in a double wall tent design too).
Posted by: arfa

Re: levitating tent - 04/20/21 02:55 PM

My primary concern is getting the pole apex at the right height. I am not sure how much allowances to make for venting and silnylon sag. Catenary curves is another variable I am not sure how much to allow for.

Earlier tents have been modeled with cardboard and tape or string and sticks - pretty crude affairs. Now I have the precision of Sketchup and can tweak down to a millimeter. Perhaps a blessing - and a curse??
Posted by: DustinV

Re: levitating tent - 04/22/21 10:17 AM

The 50mmm gap at the bottom of your tent roughly matches the gap at the bottom-back of the 'mid I use. The tie-outs default to about 3", so basically 50mm. I never get condensation.

The 950mm pole height is pretty low. However, the wonderful thing about levitating your tent is that adjustable guylines and poles can change the height instantly for different weather conditions.

It may be a good idea to build a prototype out of tape and cardboard to see if you can move around enough and find out how it will make you feel. I found out the hard way that I don't like a fully enclosed bivy as my only shelter.
Posted by: arfa

Re: levitating tent - 04/22/21 09:01 PM

Thanks Dustin. Good to know 50mm works OK. I was thinking of an upper vent triangle on the high end wall - but figure I could cut this in later if necessary.

Height: - yes, 950 is low. It was an arbitrary number. I am thinking more toward 1150 or 1200mm. I like to be able to sit fully upright. This is pretty high so I don't want to have to jack it up any higher to compensate for sag or cat curves.
Posted by: DustinV

Re: levitating tent - 04/23/21 09:46 AM

Coincidentally, my default tarp height is 1150. Headroom is adequate for me (5'10") near the pole.

I have to say I envy you having the time and tools to design your own shelter. It would be fun to play with the dimensions and shapes to create something custom.
Posted by: arfa

Re: levitating tent - 04/27/21 02:57 PM

time????? I try to spend more time using the gear smile if I can - otherwise - I make stuff for my hobby. I will probably make this over the winter (southern hemisphere). Yes, 1150 felt good in my stick and string mock up - that fell apart as I got out of it.!
Posted by: DustinV

Re: levitating tent - 05/03/21 02:56 PM

I should have said, 'time and opportunity.'
I did a MYOG project to adapt some cheap ski poles into trekking poles. The total time of the work was probably 15 minutes, but it took me 3 weeks to get the chance to do the work.