Tuesday, 10 May 2011

ModYOG, 10th Wonder Hammock

It seems that when it comes to kit there's always room for modification. I'd only had the hammock up a few times and knew there were a few little things I wanted to add or change. In spite of my initial thought that tying directly to a couple of trees was a perfectly satisfactory way of going about it I discoverd that it was easier to set it up correctly without having to resort to untying/re-tying if I adopted one of the alternative methods.

In the end I decided on tree straps and whoopie slings, the slings attached to the webbing straps using a Marlin Spike Hitch. As I already had the webbing that came fitted to the hammock I used it to make tree straps that would be compatible with carabiners although it isn't the lightest way to do it. I simply removed the webbing from the hammock and formed a loop at each end by bartacking. At present I'm not using carabiners but simply wrap the webbing around the tree feeding the free end through the stitched loop.

The whoopie slings are generally made using a lightweight high strength marine braided cord. This is pretty much the hammock equvilent of using Marine Dyneema control line cord such as Marlow Racing Excel for tent guylines. The woopie slings are made by splicing a fixed eye (Locked Brummel I think) in one end before feeding the running end through the middle of the braid for about 8" and back out again to create a slip knot that self locks when the cord is under tension (I think the locking part is called a constrictor). It's much harder to describe how to make them than to actually do it, the video linked to Here shows how it's done.

While for minimum weight I'd choose something like Dyneema SK75, 2mm diameter with a breaking strain of 900kg (and costing a cool £2/meter) or Marlow Excel D12. Rather than order the lightweight high strength stuff I bought some general use 6mm braided line from B&Q.

The whoopie sling is attached to the hammock by feeding the end with the fixed eye through the sewn in tunnel at each end of the hammock before passing the working end through the spliced eye.

To attach the hammock to the tree I simply attach the tree straps, form the marlin spike hitches by using 2 x 100mm lengths of aluminium tent pole and then loop the slipk not over the marlin spike hitch.

This obviously sounds overly complicated but it makes setting the hammock with the right amount of sag much easier as it can be adjusted without any un-tying.

With the 'Suspension' sorted I added a tying made from dressmaking ribbon/webbing to the midge netting, to prevent it being pulled through the netting I sewed on a 25mm x 25mm piece of webbing inside and outside the net to attach the tyings to. I also added 3 ribbon ties to the edge of the hammock fabric just benerath the zip to allow me to roll and tie the hammock when not actually in use.

With the easiest parts done I made a mesh pocket/pouch to hang from the inner ridge line to hold bits and pieces. I made the pocket double sided but rather than drive to town to buy some edging tape I made my own by cutting 45mm strips from a piece of ripstop nylon and passing it through a folder before pressing with a smoothing iron to help it keep it's shape.

This was a little time consuming but worked nicely in the end and I'm pleased with the finished pocket.

Finally I removed the fine but tangle prone cord from the midge net suspension shockcord, the thin cord meant that the net could be tied to the trees used to suspend the hammock but I found the shockcord work jus as well looped over the tarp ridge line and fixed with a kind of prusik loop.

I'll more than likely switch to lighter stronger cord/whoopie slings and lighter weebing tree straps at some point if I find I sleep ok in the hammock.

The next project is to make an Under Quilt, I mentioned being cold the hammock I'd borrowed from Ralph as I hadn't any insulation underneath me. While I could just about manage with a CCF mat ofr even a Self Inflate the recommended method of providing insulation underneath is to use a quilt which attaches to and hangs underneath the hammock where it can't be compressed. Again I'll take the cheap and easy option, at least for the time being by converting a cheap sleeping bag. I'm hopefully going to get the cheap sleeping bag tomorrow and can't wait to get started but 1st I'll neeed to clear a space in the garage and fit a coiple of eye bolts so that I can test the fit of the UQuilt before finalising the design.

1 comment:

  1. Sounds like you are getting there. I find it so uplifting when your thoughts are transferred into reality.
    You made a nice job of the gear pockets too. Looks very professional. Wish i could sew.