help with adjustable whoppee structural ridge line please

**billrobo** · 05-22-2014, 08:10

Hi all
I am thinking of trying out a structural ridge line for my DD Travel hammock,( this I understand to be used to have my hammock centralised in a level position), it has a built in bug net, so not sure if it will work and if it is at all necessary. First off does anyone have the measurements or info relating to making one please?
Kind Regards
Bill

**Bubba** · 05-22-2014, 08:26

The purpose of the ridgeline is to provide a consistent sag regardless of the angle of the suspension. The adjustability is to allow you to find out how much sag you actually prefer. SRL also support bugnets and allow the hanging of RL organizers. The ajustable SRL is made the same way as a whoopie sling but the measurements are different. The adjustable loop is smaller and there is a much longer distance from the fixed eye to the adjustable bury. I'm not familiar with your hammock so I'm not sure how it would be installed. I'm sure its possible though.

**billrobo** · 05-22-2014, 08:39

Originally Posted by Bubba

The purpose of the ridgeline is to provide a consistent sag regardless of the angle of the suspension. The adjustability is to allow you to find out how much sag you actually prefer. SRL also support bugnets and allow the hanging of RL organizers. The ajustable SRL is made the same way as a whoopie sling but the measurements are different. The adjustable loop is smaller and there is a much longer distance from the fixed eye to the adjustable bury. I'm not familiar with your hammock so I'm not sure how it would be installed. I'm sure its possible though.

Thanks Bubba,
I use a whoppee on either end of my hammock with a continuous loop off of my hammock which is threaded through the hammock,(threaded using a larks head) adjusting these whoppee`s seem to allow me to adjust my hang level, so is there any need for a SRL, or is it a case with a SRL i get more sag if needed?
Kind Regards
Bill

**Bubba** · 05-22-2014, 08:44

What you can do is set up like normal with a slack SRL and then get in and adjust your suspension to where it is most comfortable. Start shortening the SRL until it is taut and then leave it. Now every time you set up you adjust your suspension until the RL is the same tautness. I use mine mostly as a yardstick and don't rely on it to compensate for less than ideal tree distances.

**nothermark** · 05-22-2014, 08:44

Interesting idea...

Typically the ridge line is ~83% of the flat length between the attachment points. That is a good place to start. Not sure where I would attach it on your hammock.

The idea of a structural ridge line is to provide a constant hang angle despite poor choices in anchoring the hammock. You can easily demonstrate how it works with two pieces of string. Let one hang in a catenary droop and tie a second one accross the droop around 1/2 way up the sag amount. Now pull one end of the main cord and it will flatten but the part between the two anchored points will maintain the same sag. In a hammock there will be a sweet spot with no center ridge when that length is set properly. What you are aiming for with a SRL is to find the sweet spot and anchor that cross line to maintain it. That is why Hennessy hammocks are typically hung with minimal tension on the SRL. Too tight is too flat and too loose is baggy.

I would not use a whoopee for that as once you get the length set the idea is to keep it there. It should not change. I would use a fixed loop like a figure 8 on a bight or a bowline and a clip clove hitched to the other end so you can unhook the ridge line if you are just sitting in the hammock. Then they get in the way. Most of the time you will not load the SRL heavily because you will set up with just light tension so you do not need climbing rated clips for that. The SRL also gives you an indicator of level if you want to set up with the foot end a bit high or whatever. ;-)