View Full Version : Tyvek+HH

2003-02-13, 23:16
Im thinking of buying $13 from Andy's Tyvek site and making a Tyvek HH Explorer Fly. Ive had 3 people tell me that this is quite feasable. Im making my 1.9oz ripstop nylon "wings" for my current fly, but they are quite a hassle. So im thinking of making a fly which is 126"long by 50" wide (10.5'x4.something) I will have 25" at the widest part of the hammock- compared to 18 that i have currently. The slight catenary curve that the current fly has also reduces stormworthyness. This SHOULD provide much better protection from the elements, and its definatly large enough to provide GOOD coverage as a stand alone tarp if using it as a bivy on bald peaks- which i will be doing in the summer). People have said that tyvek eventually leaks water, but i have conclusive evidence that this is only after 2 days of CONSTANT exposure, and ripstopnylon would do the same thing, IMHO. It will only weigh 7 oz, which is less than my current fly, and its bigger. All +'s from this side of the table...more to come


2003-02-20, 20:50
Even when crinkled a lot, Tyvek still is loud to me. For something in the wind like a fly, I'd rather use silnylon. It compresses better, is just as light, and not much more expensive. For your 5 foot wide tarp, it would cost about 3x6=$18, or even better would be a full double wide tarp for actually camping and cooking when it is rainy, and you can have that for twice as much, or $36. (Plus a couple hours of sewing.)

My $.02

Now if I were making a home-made bivy and need a breathable top, Tyvek might come to the rescue (or one of the new coated breathables).


2003-02-20, 23:16
the 2 diagonals of the tarp need to be 130" long by 65" wide. Using the pythagorian theorem (remember high schoo math?), this means that each side has to be 72" long. It has to be shaped like a diamond, so it would take 3.61' of fabric to complete, if the seam of fabric is perpendicular to the hammock. THis is unacceptable. If the seam is parrellel to the hammock, the seam would be about 5 inches from the bottom, and scraps taken off the corners could be used for that. That would total the length of the fly- 130". Purchasing from owfinc.com, that would cost $21.30. It would cost the same amount either way, but from what ive heard, you want the seam Parrellel to the hammock. Heck, even sgt rock said that in his review of the moonbow poncho\tarp. Thats why it cost him extra money...he needed the seam parrel. to the ridgeline.

I also just imagined of leaving one side of the fabric straight, and not tapering it to fit the hammock. THis would wiegh only about an ounce and a half more, but would allow for a much larger area under the hammock on one side. HOWEVER, it would require the addition of 2 stakes and 6 or so feet of cord. But it might be worth it. THis could be used for several purposes:
a) a better place to store gear- its much more protected.
b) MUCH better wind protection if it is set up facing the wind.
c) a much larger tarp area for sitting, cooking, moving around in if you are banished to your hammock when it is raining. YOu might (might) even be able to fit 2 people for a game of cards:p Not that cards are ultralight....but niether is this.
d)I plan to use the hammock in the summer on 10-12 day trips through the whites. One or 2 nights will be spent in treeless areas. This would afford a much much larger tarp for hammock use a a bivy sack.

Hmm....flyfisher, you got me thinking again!! darn u!!

And just for the record, i changed the width dramaticly, becuase the fabric comes in 6 ft widths, why not use 6 feet?? Better yet, if ive got the fabric to make it 65", why not make it 65"????:confused:

Am i the only one obsessed w\ HH flys??


2003-02-21, 08:43
Ah, you are thinking a good deal.

I must admit that when I set up my HH and laid down in the fetal position and looked up at the tarp and saw that it was not covering the bug net (It was not stretched quite tight enough) I began to wonder about the small amount of overlap.

I really like the idea of getting out of the hammock, packing my pack, putting the hammock away, and then taking down the tarp, all without worrying about sticking part of my body out in the rain.... or having a bit more protection from 45 degree slanting rain. So I have opted for a couple more ounces (oh no!) and used a double wide silnylon tarp erected rectangularly instead of in a diamond.

Here is a very pretty girl in my hammock:


But what you are meant to look at is the tarp, not my wife!

When I built the second hammock, I did not put the "peaks" at the ends and will try it that way for a while to be able to compare the two.

Oh, and to let the cat out of the bag, my experiment this weekend will be in trying to hang two hammocks next to each other from the same two trees... each hammock with its hanging point shifted a bit away from the centerline.. I don't know if it will work, but it would allow us to whisper sweet nothings, and use a single tarp.


2003-02-21, 16:11
Being im only 15, this stuff is right up my ally:cool:

I want to be a structural engineer, and besides building structures out of balsa wood, i am now going to start w\ remote controlled balsa wood sail boats- i love to sail.

Back on topic: I took your rectangle design, and my diomond design, and morphed them toghether. The fly i now plan to use is a hexagon.

As seen in the picture below- ive been very busy. Thats only 1 page out of 3 ive drawn on the subject...all filled. I would have a 2 foot "flat" section on the staked out sides of the tarp. THis would allow me to purchase exactly 5 yards of ripstop nylon, which would cost just under $30. THis would require 2 extra stakes and about 8 feet of extra cord. The total wght. would come out to around 12 oz or so including ropes. my current fly weighs 9.5 oz, so this is a very marginal increase in weight with a VERY large increase in size. This is becuase im going from 1.9oz ripstop nylon(about 2.2 oz after coating) to 1.1 oz silnylon (about 1.4 oz after coating) This is almost an ounce of savings per square yard. wow!


2003-02-21, 16:47
quite cool, though I wonder where you will attach your pull outs? I often set my tarp up with only the 4 stakes. The advantage of the diamond is that it only requires 2 stakes. Will you attach multiple tie-outs to a lesser number of stakes??


2003-02-21, 17:15
It would require 4 stakes.

2003-02-22, 12:56
brian - I like your idea of the hexagonal fly. Can you share some of your ideas on such things as: dimensions; fabric and seam alignment (silnylon); attachment to the sling ropes; pitching technique for maximum efficiency in wind. I'm going to be cutting my teeth on hammock camping, in the North Carolina GSMNP back-country, in late May. From all that I can deduce, so far, we can possibly expect a bunch of rain and wind, that time of year. I do hate to sleep wet, and have concerns about the effectiveness (size) of the HH fly.

I'd also welcome tips from anybody who has experience with that neck of the woods in Spring.

2003-02-22, 13:33
ON the picture below- there is a scaled drawing of my hex tarp for the HH. Note, this is for the expedition, not the a-sym. The dimensions are as follows( look at the #'s on the picture for reference):

1)The side part of the hex is 4 feet long. The 2 guy out points per side would be located on either side of this edge.

2) The entire length of the tarp would be 130". THis is about 8 inches longer then the current fly, but it will help keep water off the hammock by covering much more of the support ropes. THis is one of the main reasons i looked into making my own fly.

3) On the sewn side, the vertical seam would be 50 inches long. Here is the cool yet trick part of the whole tarp- it would only require 5 yards of fabric. Ill explain this in my next post how this is done, but on the seam by the ridgeline (#2), there would be a 4"-5" seam allowence, so there is plenty of fabric to work with. Since that seam is so critical, there must be an adequate seam.

4) THis is 64". Just for reference.

CHeck out my next post on how i am going to accomplish the task of making this thing- this is the "fun part".

Brian- the only 15 year old in this forum.

2003-02-22, 14:06
Heres how i plan to make this beast of a HH fly.


1) I get 5 yards of 1.1 oz silnylon from OWFINC for $29.50+ s\h.
2) The fabric MUST be 62+inches becuase of the seam allowences.

3) Cut off 130" of the fabric. YOu now have a 130"x 62" peice of fabric.

4) You must now find side #1 on this peice of fabric. Find the center, and measure 2 feet in each direction.

5) Scribe a line using chalk from the each end of the 4 foot side (#1) to the edge of the fabric 60 inches (this is critical) from the side. Cut along this line. THE CUT MMUUSSTT BE CLEAN. THe result is a shape that looks like a trapezoid with a 3 inch rectangle attached to the bottom.

6) Put aside the 2 triangles that you have formed when you cut off the excess matterial for side #4. These will form the sides on the other side of the tarp.

7) Of the origional fabric, 50 inches should remain. This is is make the box in the picture. There is only one box, and this is it.. Center the fabric on side #2 of the trapezoid you have formed and sew. Before doing this, scribe a line from the tip of side #2 to the other tip of side #2. YOu want the seam of side #2 to be about 2 inches below this line. THere should be about 2 inches of fabric remaining to work with to form the seam. This is probably the most complicated step to explain.

8) You should now have a trapezoid with a rectangle sewn to it. Now go find the triangles you cut off earlier. Those will form the angled sides on the sewn side (understand that term now?). Those will be sewn to side #2 at the same level as the 1st peice was, forming 1 straight seam. Then you will sew seam #3, which will complete that side of the tarp. It should now almost look like a hexagon.

9) Where side #4 and side #2 meet, there should bea little excess fabric, fold this over to form a doubled layer of fabric, which will re-enforce the attachment points.

10) Fold over the edges of side #1 on both sides to re-enforce it. Then take the excess material that you have from seam #3 that you cut off( if you didnt, do it now) They only have to be about .5 inches thick, and you will need about 5 inches of it per guy out point.

11) Sew an attachment similar to the one already on the HH Fly. You will need 4 guy out points for the stakes, and 2 for the attachment to the hammock. Steal from your old fly or get new rings for attaching the fly to the hammock.

12) Test it. Make sure all seams hold under pressure, there are no lose threads, and that the attachment points are strong enough to take stress in wind conditions.

13) when you are sure it is fine, seam seal it. Look on whiteblaze.net for tips on seam sealing. There is a thread that currrently has 3 or 4 ways of doing it. make sure you use silicon based sealer.

14) Its done!!:D Now where is the rain??

Several Things (ideas) i thought of when writing this:
1) order 5.1 yards of fabric. Then you wont have to cut of the excess material to make the attachment points.
2) You MUST MUST MUST use 100% polyester thread. NOTHING ELSE!!
3) Go to a fabric store and buy 5 yards of el-cheapo fabric and make this. This will a) help you familiarize yourself with the proccess. b) its only cheap fabric, not $6 a yard silnylon. If you make a mistake, who cares!?!?
4)I strongly suggest doing this: Go back and use a peice of paper using the scale of 1 inch=2 feet and make this thing out of loosleaf or something. Thats what i did after i drew it out. Its amazing how much of a better understanding i had.
5) BETTER YET: order 5.33 yards of fabric- use the extra to double re-enforce the hammock attachment points. I would DEFINATLY recommend this.
6) Take your time.
7) Do #3.
8) Have fun
9) DO #4.
10) Do #3
11) Do #3
12) Do #3(u get my point)

Brian- the only 15 year old on this forum

2003-02-22, 19:45
After consideration, i would change the amound that you order to 5.5 yards. The extra .5 yards helps to guarentee that you have enough fabric on the square part of the fly to attach the triangles to it. The square part would now be cut to 57 inches. THis also makes sure that there is enough to make the parts where the fly is guyed out from.

Brian- the only 15 year old on this forum

2003-02-22, 22:41
Here is an extremly accurate comparison of the standard HH fly and my proposed hex fly. Drawing accurate to 2 pixels.