Sunday, February 20, 2011

MYOG: 10x10 Pyramid


I’ve wanted a large pyramid for a while.  Mainly because when you sleep four guys in one of these, the amount of weight per person beats most other options (including tarp, bivy, etc…). Not only that, but this provides a large area for people to chill in during storms.
I’ve been eyeing Oware and MLD pyramids for a while. But Jerry posted an article on making your own 9x9 pyramid on BPL ( http://www.backpackinglight.com/cgi-bin/backpackinglight/myog_silnylon_floorless_2-person_tent.html ), I immediately became interested. But the lack of experience using a sewing machine or making any kind of gear myself, quickly made this idea take a backseat.
In early January when I started to really think about purchasing a pyramid shelter, it quickly started sinking in how much this would cost to get a shelter, with perimeter netting and a floor.
After much planning and researching, I ordered the 1.1 ounce silnylon from Noah Lamport and all the other hardware from OWF. I think I paid around $175-$200 for 25 yds of silnylon and all of the hardware for the shelter (except for the stakes and the center pole), which included the perimeter netting. This amount of silnylon would cover making two pyramids…which is great for me because I’m going to make this shelter again. I'm also using this to make stuff sacks and a rain skirt.
For the most part, I followed Jerry’s instructions to the T in putting together this shelter. He and others at the BPL forums have been very helpful in giving me tips for this first large project. To see the full forum discussion where I got a lot of help with this, go here.
The first thing I did was I put together the cat curve jig Jerry describes in his article. I cut up a normal cardboard box and stapled/nailed this to two pieces of wood for the 108” diagonal line. I discovered that cutting cardboard is not easy to do when you want precise results. This was probably one of the largest mistakes in this project, because not all eight pieces were the same which made things interesting when we put everything together.
So in any case, I’m going to get to the point. Below are two lists that describe what I think worked extremely well for us, and what didn’t work. This is not to take a shot at Jerry’s article at all. This is meant to provide a perspective from someone who is brand new in using a sewing machine, and is also useful for me when I do this again.
What Worked Really Well
-        The massive amount of pins we used to line everything up was tremendously helpful. However, this also was very time consuming. After talking with Jerry on the forums, this is how he was able to sew accurately with just four hand stitches on the whole length. Keep in mind that he probably is able to see the line of the 2nd piece of fabric under the sewing machine (which I wasn’t able to do…more comments on this later).

“Sewing machine needle starts at one of my hand stitched (or you could use pins) aligned points. I hold the next aligned point in my hand, which is maybe 2 feet of sewing from where it currently is. I then select a point that's maybe 6 inches away from where the needle is currently and align the top and bottom and hold firmly between fingers. My two fingers not only contact the fabric, but each other, so the top and bottom fabric don't slip. Then I sew about 6 inches. Repeat...”

NEXT TIME: Following Jerry’s tips above would require much less pins than what we used, and should provide more accurate results.

But just to give you an idea of what I did, here is a photo with how I used pins to line things up. As the sewing machine approached each pin, I pulled out the pin. This worked fine, but it added a lot of time to this project.

-        We put in the zipper a little differently that what is described in Jerry’s article. We did everything that he describes in the article, right through the sewing a 4mm stitch from above where the zipper will go to the bottom. What we did after that is we pinned the zipped up zipper to the fabric, so that each side was connected to that inch or so side of silnylon.

Below is a photo of the zipper from the inside of the tent. The dark fabric is the seam allowance of fabric for that piece.


What this did was provide a small amount of weather protection on the zipper and made attaching the zipper very easy.

After sewing three stitches on each side of the zipper, we just needed to seam rip the 4mm stitch in the front of the tent. The only mistake we made with this part was that I went too high with the 4mm stitches. But I did end up reinforcing the top of the zipper.

NEXT TIME: With the zipper on the next pyramid I build, I’m going to spend more time in making sure I place the zipper exactly where I want it to go, so the top is cleaner and more re-inforced.

-        Using the ladder locks combined with the 0.5 nylon webbing makes it very easy to adjust the shelter. Using 12” of nylon webbing allows for a lot of flexibility.

NEXT TIME: I used the nylon webbing for connecting the ladder lock to the tent. Next time I’m going to use grosgrain ribbon as it is a tad bit lighter and will hopefully be easier to line up when sewing onto the tent.

-        Generally speaking, using a sewing machine is not rocket science. This was much easier to pickup than I thought it was, and I’ve very comfortable working with the machine. My wife and I were able to sew the lines together fairly accurately, and I’m very satisfied with the quality of our sewing.

NEXT TIME: Take a closer look at the final results of this tent, I did notice that some of the lines do not appear to be completely straight. I don’t think this effects much, other than looks, but next time I am going to spend more time in making sure things are sewed more straight.
-        When working with the flat felled seams, we figured out that if we put in the pins perpendicular to the seam, that we could simply sew right over the pins and pull them out later.



NEXT TIME: I wish I read this article before I finished the first tent. What I did is probably fine, but following the correct technique would have saved time.
-        The coil zipper #5 works great. I don’t think a larger zipper would be any more beneficial.

-        Zipper top and bottom stops probably made things a little cleaner.

NEXT TIME: The long zipper is great, but I think I could save an ounce or two by making it a little shorter. Maybe 6-12” shorter?
What didn’t work Well
-        The biggest thing here was that things did not line up. When we got to sewing the two corners together of the whole shelter, we were off by over an inch on each side. Obviously this was a concern when we put the whole tent together, but when I took a close look at the shelter when it was setup, it was very obvious that one of the four corners was slanting way closer to the ground than the other corners.

Here are a few photos of the sides/corners that turned out fine:


  
Here are some photos of the corner that did not turn out:



I "think" it was the fact that our cat jig quickly started falling apart the more we were using it when making the lines on the silnylon. It didn’t completely fall apart, but the cardboard did not last very long. I also don’t think our long straight edge that we used for measuring and making things square was completely accurate. All of this combined with human error probably was what made things so far off.

Also, what became clear to me with this project is that it is more important to have all eight pieces be very close to the same as far as the drawn lines are concerned….more than it is to have the cat curve be 100% accurate.

NEXT TIME: I’m going to put more thought into creating a more accurate jig. My current thoughts are to get a buddy who is very handy with wood in helping me put together one large piece that I will use as a template for all of the pieces.

-        As I was satisfied from the sewing we did, I found out we could have saved some time if we did the flat felled seam differently:

1. I would have cut the fabric 1 inch from the line and spent more time being more precise with this part. It was difficult to work with fabric that was shorter than that. There are parts in the finish product where we could not hide the raw edge in a few places of the flat felled seam.

NEXT TIME: Spend more time cutting the pieces out so that the whole pieces are more consistent.

2. It would have saved some time if we actually did the flat fell seams correctly. I think they turned out fine, but the 2nd row of stitching should be to the far edge of the seam, and then put in the third row in the middle. This would allow the third row to be put in very quickly and we wouldn’t have had to have the pins in the fabric at this point. See this article: https://www.backpackinglight.com/cgi-bin/backpackinglight/process?id=K2bWvpMP:69.146.72.74

On top of that, if we didn't rely on pins so much, things would have been faster.

-        The trekking pole setup I used seems to hold up fine (I used the Black Diamond pole connector to attach two poles). But adjusting the poles to the correct length is too much of a hassle for what I’m looking for. A dedicated pole will be more convenient and reliable.

-        A black/red sharpie is visible on dark sylnylon (barely). But why would you use this when a silver sharper will be 3x more visible? If I figured this out earlier, this would have saved a lot of time and headache!

-        For whatever reason, the zipper pull was hard to get onto the zipper tape. However, this article was very helpful in getting this on: http://www.questoutfitters.com/zipper_tips.htm
I’m confident that if I had measured the eight pieces more consistently and accurately, that my first MYOG pyramid would have been very usable. Knowing what I know now, I’m going to go through the 2nd pyramid more slowly.


4 comments:

  1. Hi Chris,

    Thanks for the posts, here and on BPL.

    I've made plenty of tarps, tents, quilts, etc, and I'm no expert. Don't be so hard on yourself, I'm sure this one will work fine. I once agonized over every minor defect, but as long as the stitching is tight everything seems to work fine in the end.

    I'm awaiting my fabric order from OWF and will start a similar pyramid once it arrives. It is for a trip to Denali (four people).

    Sincerely,

    Elliott

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  2. Thanks Elliott!

    I do believe this tent is usable. But since that one corner pitches so close to the ground, I think I would have a hard time fitting 4 guys with gear. That is the main reason I want to re-do this. In all honesty, if that one corner was the fine, I could have lived with all of the other errors in this tent. :)

    If I have anymore insights on the next one I build, I will let you know. I should have the cat curve jig done next weekend.

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  3. Hi. Some time since you've written this but thank you for a very indepth history of the making. Especially liked the "Next time" sessions, they are super helpful. I'm planning on making my own pyramid but I'd like to have one where me and my girlfriend aren't separated by the center pole. How big would you say the base need to be for that?

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  4. I usually put the pin perpendicular to the sewing line, and don't remove them until after the sew is complete. Once in a while the needle hit a pin and bends it, but it is not a bug issue.

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