half pyramid – any math whizzes out there

Seems it will only let you do some of the cut outs in one direction and not the other. Anyway, here’s what I ponied up:

Its limited in what you can adjust though, after you’ve cut all those angles in.

Dwight,

I cant stop playing with Sketchup either! Learning the tools and it capabilities.

Not as sophisticated as the software at work but defiantly worth the price we paid for it… Nada!

Dwight,
Here is another spreadsheet. Drawing is of fabric layed out flat (2 dimensional).

I’ll email you a copy of the spreadsheet.

-Lance

Rich

Could you Email me a copy of the spreadsheet as well

roger_alsborg@hotmail.com

Here’s some stuff I whipped out fairly quickly. Only problem would be getting layout patterns from any of this stuff. You’d have to use the dimensioning tool and lay it out on your own.

I figured out what was wrong with my flat pattern; I set the view up incorrectly. Anyway, here’s the updated print.

I just wanted to quickly apologize to 2D_Woman_Standing_Sandra for amidst all these graphs and sketches I seemingly forgot my manners.

Too late. She told me you were, flat out, just a plane in the rear.

I heard she thought you are kind acute, even if your humor is a bit obtuse. If you would get to the point, quit being so two dimensional and give her a sine, she won’t think you’re a square, will stop circling the wagons, show you some curves and make a straight line to you.

That’s pure Hyperbol

you guys are funny, arc, arc, arc, arc.

Oh Lance, that was the longest string of puns I’ve heard since Junior High.

Here’s something I laid out to illustrate my reasoning that that angle at that point we were trying to calculate will always be 90 degrees.

Regardless of the size of of the sidewall depth in relation to the backwall width, the sidewalls are always going to be bisecting an equilateral triangle, thus giving a 90 degree angle.

I’ve laid this out in a circle, as would be done geometrically, to show what I mean. I had some blue lines to show the extent of the side triangles if we were going to layout full sides instead of half sides, but they didn’t show in this image.

So, instead we see the extent of the base of a full pyramid side, but only see lines connecting to the center for the areas we would finally cut out. I hope that makes sense.

I haven’t had the time yet to recheck my trig on the spreadsheet I was doing, but I’ll try soon. Any feedback on this logic?

If you all come up with a consensus on a design
and want a batch made, let me know. You could
name it, maybe something related to the forum
etc.

I have toyed with the idea of adding an overhang to
the front of a similar shape. Also I have some 72″ wide silnylon now too that may help in eliminating seams.

B.P.L.amids?

Regarding a consensus on a design, seems there’s too many folks, too many different levels of experience, too many needs, too many different desires for comfort, or lack of, etc.

Dwight

like this? Or probably something that would pull lower if needed.

Maybe I’m missing something here, but it seems like we just re-invented the Dancing Light Gear Ultralight Brawny Tarptent (see a BGT review), or maybe the DLG Tacoma Solo. Of course, DLG isn’t manufacturing anymore… but it looks like this problem already has at least 2 solutions. I’m confused on how these proposed designs are different/ better.

Oh, and I do appreciate the software and modeling tools that have been mentioned. That’s good stuff.

-Mark

Because reinventing is the cousin of MYOG.

I did find the Brawny online after I fooled around with the tet idea, though. Of course, I was pretty sure it wasn’t original when I thought of it.

Seems like the cat tarps are a more efficient use of material though.

Dwight

“Because reinventing is the cousin of MYOG.”

Great point! I figured it was either:
1-A problem-solving exercise from scratch to learn the tools and products, sort of hacking and reproducing.
or
2-Improving the design or features of something already available. I didn’t think I was seeing anything ‘new’, so I just wanted to make sure I wasn’t being a blockhead and missing something cool.

Like in this case, I know sometimes I just have to start with a clean sheet of paper and think it through, even if I’m retracing someone else’s steps. For me, that critical thinking is one of the best parts of UL hiking.

Anyway, I appreciate seeing everyone think out loud on this one.
-Mark

For me it was also item 1, going through the steps myself so I know the why’s and why nots for if I ever do do something original.

Its also encouraging that I come up with ideas that have been implemented commercially by more accomplished tent builders.

To determine the dimensions of a seamless conical tent made from a roll of tyvek could be (aka limited to 9ft in one dimension)

If I could remember what in the world I did and where in the world I put my notes… I stumbled upon an equation that would have helped with this discussion and with determining dimenstions in general… but, I can’t find it…

Anyhow, very interesting work everyone…

Oh, and Dwight, you are correct on the 90 degree angle thing. Well, at leas you are correct if you want there to be a straight line (when viewed downward from the top) between the two leading corners going through the tip of the pole.

Thanks for the validation on that Josh. And you’re right, I’m assuming a right angle for the face of the tent to the ground.

http://www.snowpeak.co.jp/catalog/spo/html/2006/pentaease/pentaease.html

やはり、スノーピークのサイズぐらいは
必要と、JSBは考えています。