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erichlf
03-03-2005, 18:58
When I set up my hammock this weekend I was having trouble getting the ridgeline of the HH UL Backpacker fly to become taut. Any suggestions, or comments?

peter_pan
03-03-2005, 21:43
One more time ! ......Taut Flys and tarp are the ones tied to the trees...not the hammock line.....shock cords, sling shot material and weights are all nice work arounds to fix a poor engineering feature, ie. use of the tie on the hammock line....."tis far better to eliminate the problem....tie to the trees.

erichlf
03-03-2005, 21:58
ie. use of the tie on the hammock line....."tis far better to eliminate the problem....tie to the trees. And doing such a thing will end up adding weight and hurting the tree bark, but thanks for the suggestion.

SGT Rock
03-03-2005, 22:04
Set up on trees that don't sag :D

erichlf
03-04-2005, 02:49
Set up on trees that don't sag :D Real funny. It seems to me that if the fly had a catenary ridge one would have less problems with tensioning the ridgeline properly. But, I suppose it takes a little practice setting up and I have only setup the hammock 3 or 4 times.

SGT Rock
03-04-2005, 08:55
Tom is is/has coming out with an auto-tensioning device, basically it adds weight to the side tie outs, That I used to do and still often do in bad weather is tighten the sides first until they pull the center ridge-line tight over the bug net, then tighten the end pulls until the tarp ridge-line is sort of "U" shape.

hungryhowie
03-04-2005, 09:34
When I set up my hammock this weekend I was having trouble getting the ridgeline of the HH UL Backpacker fly to become taut. Any suggestions, or comments?

Well, here's an explaination for you, anyway.

Tom Hennessy's poorly-designed rainflys are what started me down the road to exploring making my own hammocking gear (previously I'd made a bunch of other stuff, just never any hammocking stuff). The Hennessy rainfly was designed under the premise of saving material, even when it meant sacrificing performance.

Silnylon, like many materials, has different stretch characteristics depending on the primary direction of applied stress. In the case of silynlon, it stretches the least along its length and most along its diagonal. Therefore, for something that requires tension (a tarp, for example), it's imperative for the primary direction of tension to run lengthwise to minimize and create uniform stretch.

Yet, Hennessy continues to cut their flies on the orthoginal, meaning that despite one's best efforts, it is actually impossible to effectively tension the fly.

Call me crazy (or perhaps I"m too picky), but I found my fly inacceptable because it actually created a wave pattern that held water. In the morning, there would literally be a gallon or so of water sitting on the rainfly.

Has Tom never used one of his products and wondered why they perform so poorly?

Moral of the story, never purchase or make a silnylon rainfly with a ridgeline that does not parallel the primary direction of stress. It WILL perform poorly.

Also, the myth that the rainflys are not taught when connected to the suspension line is 90% resolved when using a properly designed rainfly. I routinely set up my hammock (including rainfly on suspension line), get in the hammock to let it settle, retighten rainfly on suspension line, and that's it. It's fine for as long as I'm set up.

-howie

peter_pan
03-04-2005, 09:56
Ok...let's look at the ridge line......first, the HH fly has no ridge line...hence the poor pitch qualities and the puddling problem that Howie mentioned...For the record, I've experienced the HH puddle before switching tarps.....Note also, inexpensive ground designed tarps 8x10, ie. with the seam on the 8 foot axis will also be floppy and will puddle because the seam is not on the ridge and "extra" material in that pitch will fill with water. Also, 8x10 or even 10x10 hung on diagonals or semi diagonals will experience the same ridge line ( more correctly lack of ridge line ) problems.

It is not necessary to have a catenary cut ridge line. to get a taut pitch....to do so is to actually limit the range of pitch options as a tarp with a catenary cut ridge must be pitched on a variant that uses the "Cut" or some "A" ... otherwise it will flop as there is no longer a universal plane of a versitile flat tarp.

Some example/points. The Mac Cat, a great tarp, DOES NOT have a cat ridge, it has cat sides...it is the inboard side tie out points that allow for the tautness....when properly staked, it causes the ridge to take up a proximal cat appearance.

An 8x10 with the ridge on the 10 foot axis, if tightly staked at the # 2 and 4 tabs as well as the corner tabs will take up a minor cat appearance.

The JRB 8x8, with its ridge line on the diagonal, will draw down to a cat like curve with use of only two tie outs total.

peter_pan
03-04-2005, 10:06
erichlf,

As to weight and tree damage....

Two 9 foot lengths of 2mm accessory cord weigh 0.7 oz........the shock cords and bungies and water funnel accessories that folks use to " jury Rig" a work around on the tie out guy line all weigh more than that.....considerably more on a percent basis.

I've not noted any damge when taking down my tarp....it doesn't get the 150-230 lb force hung in the middle that a hammock imparts....if one is still concerned, the tie can actually be to the tree hugger straps....thus a guarenteed LNT and still a non-moving (non-sagging) tie point.

pan

hungryhowie
03-04-2005, 10:19
It is not necessary to have a catenary cut ridge line. to get a taut pitch....to do so is to actually limit the range of pitch options as a tarp with a catenary cut ridge must be pitched on a variant that uses the "Cut" or some "A" ... otherwise it will flop as there is no longer a universal plane of a versitile flat tarp.

Some example/points. The Mac Cat, a great tarp, DOES NOT have a cat ridge, it has cat sides...it is the inboard side tie out points that allow for the tautness....when properly staked, it causes the ridge to take up a proximal cat appearance.

I agree with this. In fact, from my tests, for hammocks with a fly attached to the suspension line, it's better NOT to have a catenary ridgeline. The best answer is to have a straight ridgeline with catenary cuts along all edges (ala MacCat).

For flies that are attached to the suspension line, the straighter the line that the ridgeline will hold the better, and for silnylon, this means that the primary direction of stress should parallel the length of the fabric.

-howie

SGT Rock
03-04-2005, 10:35
erichlf,

As to weight and tree damage....

Two 9 foot lengths of 2mm accessory cord weigh 0.7 oz........the shock cords and bungies and water funnel accessories that folks use to " jury Rig" a work around on the tie out guy line all weigh more than that.....considerably more on a percent basis.

I've not noted any damge when taking down my tarp....it doesn't get the 150-230 lb force hung in the middle that a hammock imparts....if one is still concerned, the tie can actually be to the tree hugger straps....thus a guarenteed LNT and still a non-moving (non-sagging) tie point.

pan


And if you are concerned about the slight amount of tree damage that 2mm cord causes, you could always use some 550 cord sleeve to "spread" the load and soften the cord to the tree bark.

Honestly though, as Peter Pan said, this is really a non-issue.

erichlf
03-04-2005, 12:59
I've not noted any damge when taking down my tarp....it doesn't get the 150-230 lb force hung in the middle that a hammock imparts....if one is still concerned, the tie can actually be to the tree hugger straps....thus a guarenteed LNT and still a non-moving (non-sagging) tie point. Good point. I don't know I didn't think of tying to the tree huggers. It was hard enough for me to decide and by something as heavy as the HH UL Backpacker. I was originally going to go with the racer, but REI had mine on sale for $67. Since I had never tried a HH $67 was much better than $169 and a pound less, so I went for the heavier weight. Considering the fact that it seems to be able to hold both my wife and my weight easily I think I made a good decision. I am pretty sure the Racer would not be able to do that. Any way, I think I will probably make my own tarp, mainly because there were other things that I did not like about the HH fly. For one I do not like the shape. I think that it could be a little wider and have the "head section a bit longer. This would provide for more protection and the ability to cook under it with minimal weight gain. I think it may gain 2 ounces with how much I would add, but would gain mayb 10 sqft.

Crash
03-04-2005, 20:13
Strange I dont have the tension problem. I must be doing something wrong. :datz

ocourse
03-04-2005, 21:33
I have the HH Cocoon and have no problem pitching the canopy at all. I have never had trouble with water pooling, either. It is always taut and never has to be re-positioned. It is hard for me to understand why there is a problem. Seems very well designed to me!

tlbj6142
03-04-2005, 22:52
Its easy to make it taunt when you are not in it. However, once you get in the hammock, the ends of the fly move closer together making the fly flop around.

Check out the wonderfully written instructions for adding sling shot tie-outs to the HH fly...

http://www.whiteblaze.net/forum/showthread.php?t=3859

The HH fly is not perfect. Its a bit small, but you can make it work. That said, for couple more ounces a bit larger one would be nice.

ocourse
03-05-2005, 07:05
I can understad that the tarp ends would move in slightly once weight is in the hammock. But when I get in, there is no appreciable change and the canopy stays tight. Maybe tie the hammock tighter and use the thicker trees mentioned above?

attroll
03-05-2005, 07:23
I know where Erichlf is coming from. I am having the same problem. It is not the trees that are the problem. I have tied to 2 foot diameter trees and still have this problem. It is not the tarps ridgeline that is the problem. The tarp is not the problem. The ridgeline stays tight when I get in it. It is the hammock that sags down when weight is put in it. It seems that the cord that is tied to the tree huggers stretches when weight it put in the hammock. In doing that the tieouts become losoe. The only way I found to fix this was to tie the tarp directly to the tree hugers or to the tree itself and not use the hammock rideline.

SGT Rock
03-05-2005, 09:32
Well maybe it is the user weight that is the problem ;)

oldfivetango
03-05-2005, 11:32
And doing such a thing will end up adding weight and hurting the tree bark, but thanks for the suggestion. You can carry a small amout of plastic hose(sold at Ace Hardware for
for drip irrigation line-about 1/2 diamter and very lightweight).Run your line thru the hose and tie the cord or use a small carabiner.For convenience i use a load lock device i got at Northern Tool and Equipment(i luv that place) which probably weighs about 3 oz.You pull the paracord or what ever your tarp rideline is and then put your conventional tree huggers and HH in place first.(you could buy another set of huggers for the tarp line if you wanted to btw.Maybe not a bad idea as they could be a spare if you happen to lose one) Once you have the hammock in place you position the tarp over it for maximum protection and then stake that bad boy down.
There is a big plus to using a separate line for the tarp.Let's say you wake up to a nice little drizzling rain the next am.You are now all set to take down and pack up the hammock,roll up the bag,pack your pack,cook breakfast etc,and you will not be doing it all in the rain since your trusty tarp is not dependent on the hammock line for support.
Cheers to all,
Oldfivetango:jump

titanium_hiker
03-05-2005, 20:51
Oldfivetango, you are so right about the rain take down.
titanium_hiker

erichlf
03-06-2005, 14:53
Okay I suppose a little better explanation of my problem is in order. When I tighten the fly up before I ever get in I am already having the problem of the "ridge line" being rippled. The only reason I really care is that in high winds this will be extremely noisy. Now that being said any one have any ideas what I am doing wrong?

peter_pan
03-06-2005, 15:22
Are you tying to the trees or the hammock line ?

Youngblood
03-06-2005, 16:37
Okay I suppose a little better explanation of my problem is in order. When I tighten the fly up before I ever get in I am already having the problem of the "ridge line" being rippled. The only reason I really care is that in high winds this will be extremely noisy. Now that being said any one have any ideas what I am doing wrong?
Nothing... silnylon is an orthogonal woven fabric (threads running parallel to the length of the fabric are woven with threads running orthogonal or 90 degrees to the length of the fabric). The bias of the fabric is at angle to these orthogonal woven threads and the stretch of the fabric is greater on a bias angle. Hennessy's one-piece asym tarps have their ridgeline on a bias angle of the orthogonal weave.

My experience with the one I had was that it was impossible to pull the center of the tarp taut using the four tie out points... at best I ended up with the rippled ridge line as you described while the perimeter of the tarp would be taut. In rain, it is best to pitch the tarp with a steep A-frame so that water will drain off instead of possibly forming large pools in these ripples.

A secondary issue is the one that Peter Pan has mentioned: if you attach the tarp to the hammock support lines you will likely lose whatever tautness you had due to two things. First, the horizontal distance where the tarp is attached between the hammock support lines changes when you get in the hammock due to the sag caused by your body weight. Second, the vertical distance the sides of the tarp are above the ground also changes when your body weight causes the hammock to sag closer to the ground.

Youngblood

Waucheesi
04-14-2005, 20:21
One more time ! ......Taut Flys and tarp are the ones tied to the trees...not the hammock line.....shock cords, sling shot material and weights are all nice work arounds to fix a poor engineering feature, ie. use of the tie on the hammock line....."tis far better to eliminate the problem....tie to the trees.
When you tie off to trees, are you using a new ridgeline or just attaching to the lines which are already on the tarp? Does it matter? May sound like simple questions, but I am trying to learn. Thanks for your help.:)

peter_pan
04-14-2005, 21:27
I put a 9 foot line of 2mm accessory cord on each corner of the tarp... works fine.

Pan