Pyramid tent – 11 x 11 feet

Holy Cow, that is a huge tent! Workmanship looks excellent.

Ryan

Yes Ryan, it is mighty large!

The idea was to have something light enough for backpacking but big enough for the whole family. Also, it packs fairly small and is easy to take on an airplane. Finally, it is suitable for car camping when we cannot bring our big, heavy tent.

Very impressive, That must have been a nightmare to sew…cat curves and all.

Dave

Nice looking tent, good job

What do you mean 3/4 inch per foot catenary? The ridges must be about 9 feet, so that would be 6 3/4 deflection at the center?

How did you botch cutting the catenary curve, did you make a template and use it to mark where the cat curve is for each piece?

Did you find the vent effective at reducing condensation?

Looks terrific, Elliott.

That's a heroic bit of sewing!

As with Jerry, keen to hear about the effectiveness of the top vent.

Andrew

Very nice work!

I have been building up my sewing skills with the intent to eventually build almost exactly what you have going on right there.

Very nice work…

BM

David: It was not particularly difficult to sew. Mostly straight seams, although some were pretty long. The catenary curve was no problem since it's mostly straight at the level of a foot or so. I just pinned all the seams and it worked fine.

Jerry: Yes, about 12 feet of ridge line, half is 6 feet, so about 6 inches catenary at 1"/foot. I didn't use a template, instead I marked one piece and lined another below it and held them together with clips while I cut. It worked fine on three of the big triangular pieces. On the door piece the zipper and flap in the center caused some problem so when I was done, much to my chagrin there was an extra inch of fabric cut off compared to the other panels. All my fault for taking short cuts due to time pressure. Could have been avoided if I was more careful or if I used a template for each cut, rather than cutting two edges at once.

Jerry and Andrew: I think the vent is too small, although it was quite humid each night and it rained a few times, so it is possible even a larger vent would not have stopped condensation. The condensation actually wasn't that bad, no drops raining down, but the walls were fairly moist in the morning, and you got wet if you rubbed against them.

Ultra Magnus: Sewing such a tent does not require great skill. If you can sew a straight stitch and a flat-felled seam, and a little zig-zag for reinforcement points, you can do it. Cutting is tedious but straightforward. Design is a different matter, you really have to think through everything carefully (and be comfortable with simple geometrical calculations). On a small project you can mess up a piece and just rip out a seam or two and make a new one. On such a large project the pieces cost too much. All the better if you can get a design from someone else.

I did manage to catch a fold or two and had to rip out some stitches and sew again, then seam-seal the holes in the fold that got caught.

All the cutting, sewing and finishing maybe took 20 hours, I didn't keep track. Not that long if you spread it out. Having someone to help with the cutting can save a bunch of time (I had some help, not much). Having a large space to lay out, measure, cut and sew would have helped (I did it all in a not terribly large dining room and living room).

"Jerry: Yes, about 12 feet of ridge line, half is 6 feet, so about 6 inches catenary at 1"/foot. I didn't use a template, instead I marked one piece and lined another below it and held them together with clips while I cut. It worked fine on three of the big triangular pieces."

That's about twice the deflection that I would do the next time I made a tent, but I'm not sure. Is this what you'de do the next time you made a tent based on your experience?

I've tried doing catenary curves using the mark one piece and line up others/use clips/etc. The results weren't as good as when I spent more time and made template. I think that if you're going to spend the time and money to make a tent, better to make template.

regarding vent – I made a tent with vent maybe 2 or 4 times as big, but it didn't seem to make much difference with condensation. I think maybe a vent like that doesn't really work hardly at all. You need to have a big vent – like leave the door open – that makes a difference but even that isn't perfect.

The other thing with a tipi, is that it's big enough you can move around without touching walls, and the walls are steep so any condensation will just drip down to the edge, and then the ground. And the wall is far enough from your face that your breath won't condense on the wall.

Sweet,

Haa its huge and weighs less than my old A frame 2 man tent.

Nice job.

Jerry: I also think I used about twice as much catenary as needed, but I have little experience with catenary cutting and don't know if 1/2 inch/foot would be enough. If I made another of the same size I'd go with the smaller catenary. I think 1 inch/foot cut out too much living space.

It might be possible that 1 inch/foot is ok on smaller tents, where it doesn't add up to much because the ridge seams are not that long, but is too much on big tents which have long ridge seams and you land up cutting out 6 inches in the center (where in hindsight 3"-4" seems about right).

And I definitely would be more careful doing the cutting next time. It's not really a big deal that I messed up, you have to look carefully to see the asymmetry, but as all MYOG folks know, every little mistake looms large in your mind.

Sounds as if a larger vent would not have helped much, as I suspected.

So it sounds like you and I are consistent – 2.5 inch for a 9 x 9 x 5 foot high tent

Definitely not being critical of not using template, especially because I've done the same thing, maybe someone else that's reading this will learn from our experience.

Just saying!!! Your work is an inspiration to us who have squirreled away a ton of Sil-Nylon and are trying to think up things to make with it!!!

Jerry: I think it's important to discuss one's mistakes as well as one's successes. Some MYOG posts sound as if the person started with no knowledge, came up with a perfect design, didn't make any construction mistakes, and voila, out popped a perfect piece of equipment. I much prefer to hear about the screw-ups so I can avoid them myself. And Roger C. once wrote that he doesn't get a project right until the fourth or fifth attempt!

I know I've avoided mistakes because others listed theirs, and I plan to return the favor. I hope other MYOG enthusiasts do the same.

I thought I made a mistake once … but I was wrong

Robert: Ah, the old squirreling away of silnylon problem…so I'm not the only one! I typically buy from OWF and they give a big price break at 20 yards of one type of fabric, so I usually buy that much or more. The result: lots of fabric always laying around. The big pyramid used up a lot, though, but I still have plenty for a one-person tarp, maybe a smaller pyramid, and who knows what else…

I am in an area where Walmart regularly got silnylon in the discount fabric racks. No one in SC seems to even know what it is! They are shutting down all of their fabric sections so I bought all I could find at $1 a yard. I think I have about 80 sq yards lol. How much did you use on your tent?

Robert: The 11' square pyramid uses about 22 square yards of material, giving around 2 lbs of fabric. Using 60" wide fabric and assuming no waste gives about 14 linear yards. Adding waste gives maybe 15-16 linear yards of 60" fabric (I planned the cutting carefully and had little waste).

Elliott- I've been going back and re-reading this thread. I do have one more question, how did you handle cutting pieces of fabric that large? I mean, it must take quite a bit of floor space to roll it all out to mark and cut. I'm thinking how I would do it at my house- I've got a pretty huge family room if I were to push all the furniture out of the way, but it's carpeted, so that would be a bit of a problem…

My best bet would be to probably do it at work. My boss wouldn't mind and I've got enough shop floor space…but it'd need to be cleaned pretty well first…

What would be ideal would be a giant 6' x 20' cutting mat…

thanks
BM

… how did you handle cutting pieces of fabric that large? I mean, it must take quite a bit of floor space to roll it all out to mark and cut. I’m thinking how I would do it at my house- I’ve got a pretty huge family room if I were to push all the furniture out of the way, but it’s carpeted, so that would be a bit of a problem…

My best bet would be to probably do it at work. My boss wouldn’t mind and I’ve got enough shop floor space…but it’d need to be cleaned pretty well first …

consider just sweeping the floor well and taping down builder’s paper over a large enough area. You might also find that the builder’s paper makes a very usable pattern for cutting (it’s worked for me)

What would be ideal would be a giant 6′ x 20′ cutting mat…

lots-o-luck on that, he-he. I have good luck anchoring large fabric pieces to concrete floor by putting down a couple layers of duct tape where the corners of the fabric lay and then pinning thru the fabric and tape (pins basically parallel to the floor and pointing towards the center of the fabric piece). Lay the cutting template on top of the fabric and slide your cutting mat under it all, moving it along the cut line as I go.

Also, I’ve found that largish cutting mats are less expensive at hobby shops than at fabric shops or sewing centers (but they don’t seem to handle the really really large ones)

Good luck on cutting. I emptied out my living room and it was just barely big enough. Note that the largest pieces are about 11' long and 60" wide, the lower trapezoidal pieces on each wall. I just unrolled the raw material and used whatever width it had, then cut out the 11' trapezoids, each one flipped top-to-bottom so that the the short edges matched and I got almost no waste at the ends. Actually I seem to recall I made the ends longer than needed so that I could cut another piece out of them (the door pieces, I think).

Things got real big and unwieldy when I started joining the large pieces, though, but the cutting is all over by then.

You guys have given me some really good suggestions. I bet I could get all the cutting done in a couple of hours if I do it here at work on a Saturday. the builder's paper is genius… I could sweep the floor really nice, lay down a bunch of that stuff, mark it up with my cut lines with a sharpie, and cut it pretty easily that way, I would think…

I imagine for the cat curves it would make the most sense to sew the smaller triangles onto the tops of the large trapezoids first, and then use a template to mark and cut?

To top it all off, the shop here at work is air conditioned :D.

Thanks again!
BM

Yes, sew the wall pieces together before cutting the catenary. Best is probably to make a template, then cut each edge separately. Don't use too much catenary as I did, I think 1/2" per foot of half-edge length should work (i.e. use 3" a 12' edge). Others may say to use more catenary, though. I tried cutting multiple edges at once and messed up a little.

Elliot
Nice looking tent. SOmething like that is on my MYOG list as well, perhaps to put a titanium stove in. As for patterns, I'd agree with the design time involved- do you have any patterns you'd be willing to share? I would love a closer look at how the pieces might go together- well within my skills, just need to devote the time to it.
Thanks for sharing.
Dana