Background--this last year I've been working on bridge hammock systems that let me close up one end of the tarp, for heavy weather. I reduced the spreader bar at the foot to 18" , and was successful last winter in pitching a JRB 11'x10' tarp with one end completely buttoned up, facing into the wind.
As warmer weather came on I wanted to have that kind of protection when needed, but with less tarp. I remembered one night at the spring 2008 MAHHA where I had my hammock under a MacCat Deluxe, and wind-blown rain was coming at me from an open end. I put a DriDucks poncho into service and it worked well.
Well I don't carry the poncho normally, and so I thought I'd cook up a DIY removeable beak out of silnylon. Carry it only when the weather forecast suggests it is prudent. The finished dimensions are below. Think of it as two identical trapezoids that are attached to each other. The outside edges are simple roll seams, and the seam that connects the trapezoids is a flat fell seam. The four corners each host a tab of 1/2" grosgrain for connection purposes, as do the two ends of the connecting seam.
Just to illustrate it's size, I've hung it over the tarp suspension in the picture below.
Here the flat long edge is away from the tarp, and the angled sides are on the tarp side.
The dimensions are cut assuming that the tarp end that takes it is pitched close. The picture below has the foot end pitched close to the ground while the head end is wider (as it needs to be for the head end of a bridge hammock).
The beak is attached to the tarp suspension using with a clip that attaches to a moveable loop of cord on the suspension. The picture below is how the tarp attaches to the ridgeline, the beak attaches in exactly the same way, with a loop that is just an inch or two further up the suspension cord from the one seen below. (Also, deployment of the beak does not require a separate ridgeline).
The beak slides over the tarp. At the bottom, one set of lower corners connect to the tarp corners with minibiners, and the others come together (have loops of shock cord in their tabs, and are fastend at a common stake. On top the "away tarp" tab passes just a few inches over the tarp's ridgeline tab. The "on tarp" tab can be secured (although I'm not convinced this is necessary) with a bit of shock cord that extends from it along the spine of the tarp and connects to the D ring on the tarp ridge at the other end of the hammock.
I've sewn 6 overlapping tabs of Omnitape to secure the edge of the beak. Each tab pair is 2" in length, and these are spaced every 8 inches.
Various views of the beak in use. The hammock involved here is a BMBH with a foot end speader bar that has been shortened to 20".
I weighed this at 5.5 oz, including the spine bit of shock cord and three minibiners. Added to the 11.8 weight of the MacCat Deluxe, that brings the total close to what a JRB or Speer winter tarp weighs, and so from that standpoint one might well wonder why bother. I can think of three reasons
- this beak works with the Spinntex version of the MacCat, indeed one could make the beak from Spinntex to knock the weight back farther
- I can just leave it behind when I'm sure enough I won't need it, and bring it when I might.
- When I do bring it, I can press it into dual use as a gear hammock.
While motivated by the needs of a bridge hammock, the design clearly might be used by other hammock types. It is not so clean a design as the various doors people (including me) have built for tarps, but is driven more by the desire to have the flexibility of removeable doors but without having to modify the tarp. So in that I think this is potentially useful design.