Project Goals:
1. Make a DIY hammock that is comfortable. My approach is to use a suspension that allows a lowered footbox. I will also work to acheive a flatter spread through the shoulder area.
2.Keep the weight about equal to the hammock system now in use. While not losing any functionality (bugnet, pockets, etc.) Any weight increase will need to be justified by additional warmth, comfort, or convenience of use.
Project Description:
I have started with the Byer Mosquito Hammock and made a conversion to a bridge styled hammock. The materials of the hammock; nylon body, netting and zipper were utilized. It may have been cheaper or more convenient to start with the Byer hammock rather than buy these materials, but not by much. Another small advantage was that the hems on each end that the original suspension lines were attached to, were useful for inserting webbing for my end caps. But here again, the time savings compared to starting from raw materials didn't amount to much in relation to the overall work involved.
The suspension design benefits from the long thread on Bridge Hammocks by Grizzly Adams. However, this project explores a pretty radical departure regarding connection of the hammock body to the lateral lines.H3_profile_ sansridgeline.jpg
The Process:
Hammock Body:
This photo shows the body shape. bryer-newshape.jpgNote the orange lines, the material was later cut at those lines (and reattached later). This created a bilaterally symmetrical shape which was easier to work with- less confusing. Notice the four strips of webbing running across the width. The top webbing is at the neck line, the bottom webbing is at the knees, and the middle two are positioned above and below the butt. The idea is additional reinforcement and for more comfortable contouring in the drape of the hammock fabric. The part that extends beyond the yellow tubular webbing gets trimmed off later.
Lateral Support:
The yellow tubing is only at the edge of the material in the center portion of the hammock body. At both ends the webbing begins to veer out wider, while the cut of the fabric is becoming wider still. The tubular webbing stops about 8" before the top of the hammock and stops at the other end over 18" before the bottom hammock edge (foot). This webbing is just over 40" long and is the only area that is rigidly attached to the lateral support lines. A 10" portion of this is detached from the lateral support lines in the area of the shoulders. This creates two good billows that expand around the shoulders- very effective.
In this drawing, you can see the rope has been drawn with yellow highlighter.support_structure.jpg This illustrates how it weaves in and out of the hammock body and does not form a full length rigid attachment to the lateral support webbing- as other bridge hammocks use. This is the key to freeing the footbox to angle down slightly. A side benefit of this design approach is the lowering of the spreaderbars- essentially by raising the middle. This comes at a cost, by having the effect of reducing stability. One way of compensating for that is to make the head spreader bar wider and the foot spreader bar shorter- which I have done.
End Support:
To give supportive structural attachment to the hammock ends that hang out past the rope/webing attachments webbing loops are used. webbing_circle_ends.jpgThey encircle each end cap and are also attached to the lateral lines, but in a way that allows some movement as tensions get distributed. The webbing inserts easily in to the factory sewn hem at the ends. I rolled the hem back over itself and sewed a seam creating a hem loop of double material thickness for added strength.
Bug Netting:H3_profile_ ridge_open.jpg
In an attempt to keep the netting area as small as possible, while not becoming difficult to use the factory provided zippered access, I installed two elastic cords stretching from knee to neck. They form lower netting panel insertss nearly 6" tall. But only when the hammock has weight in it, do the netting panels fully raise up on the sides (similar to the sides of a child's playpen). elastic_crib_detail.jpgThis serves to keep things contained, but it also is designed to take tension off of the zipper when operating from the inside when the hammock is occupied.
I was pleased with the implementation of the 18" aluminum tent pole at the head end of the netting. H3_head_entry_closed.jpgIt keeps the fabric away from my face while keeping the profile low. A side benefit makes it easier to twist the netting out of the way when entering the hammock.
Additional Features:
The closed off foot box allows me to extend two elastic cords in opposite directions to become ridgeline segments. Both attach to the carabiner used to hang the hammock ends- keeping setup more simple. When taking the hammock down, each ridgeline segment is used to wrap the rigging at either end to prevent tangles between setup times.
The hammock is lined on the inside with wickaway fabric. H3_head_entry_open.jpgIt is very stretchy and feels like a high-tech t-shirt material. It serves as a sleeve for my pads (I have the Down-To_Earth closed cell- 4.2 ounces , I have an InsulMat Max Thermo open cel- 19 ounces, and a Stephensen's DAM- 26 ounces; to give a wide spectrum of comfort ranges).
Summary:
So, how well did I achieve the project goals?
1.Comfortable? Yes! It is very supportive and comfortable. However, it is slightly less stable as compared to a HH ULBP (especially noticed when operating the zipper from within). This will need to be worked on. Perhaps part of the solution will come with experience, when I find the optimal tension and tree distance for instance.
Fully Functional? I believe so. The bug netting is working and it's an economical design weight-wise. I will have to see if it feels too confining. I knew that the netting had to flex with the hammock in order for a zipper closure to work very well. In fact, there are two places where the zipper needs to have the fabric held (reducing the local surface tension by hand) for it to close smoothly. These are the places where the zipper makes a big turn twards the midline of the hammock.
2. Weight comparison. My total weight with the straps and a lightweight poncho/fly is just under 3 pounds. The hammock is 2 pounds. and 1 ounce without the fly and straps. Since the liner that holds the pad is integrated in my hammock, it is only fair to compare against the HH ULBP with SuperShelter. Total weight of HH (with Snakeskins and SS) 2 pounds 15.4 ounces. That is about 4 ounces less than my hammock when used with the DTE closed cell pad. And although my new configuration is at least as warm (with the included liner) as the HH with SS. Still I would have to conclude that the weight goal has not been fully met. I do have a few ideas for the next one though...
Final Thoughts:
Would I recommend this conversion project? Only if you have an extra hammock and lots of patience. More importantly, look at the suspension ideas and see if any of them will help you.
BTW making a hammock has been my very first sewing project. It did, however, take me 3 tries to get it to an acceptable level. So be encouraged when you take on your next DIY project. If I did it- you can too.
Reply With Quote
Bookmarks