Monday 1 April 2013

Bugsy MYOG


I always carry some kind of bug protection on 3 season hikes, a head net and bivy are the norm. The head net comes on at breaks and can also be worn when hiking if the buggers are particularly bad. A bivy offers overnight bug and additional weather protection. Problem with the head net is that while it does provide good bug protection when hiking, it isn't ideal for breaks. Even basic chores, like eating, are hard. You are also still vulnerable to being bitten elsewhere with the minimal protection offered. A bivy can offer good protection once zipped up in camp, but you have to choose between the maximum ventilation of a full net bivy, or the weather protection of an enclosed bivy. Few offer both features, and if they do then they are heavy. Mesh head areas can help you ventilate in an enclosed bivy, but you will still overheat on a hot night. With the PCT coming up, with it's wide range of conditions, I thought that there had to be a better way.

Bugsy setup for maximum ventilation
My wants
  1. It should be spacious (for a bivy).
  2. Offer full protection from all bugs.
  3. Act as a standalone shelter to protect from windblown sand in the Desert. 
  4. Ventilate like a net bug bivy but provide the weather protection of an enclosed bivy.
  5. Wearable at stops so that I can rest, eat or study the map in peace.
  6. Work with all tarps/shelters.
Wants 1 and 2 are easy. If it is sealed, and uses no-see-um netting, then it will be bug-proof. If I’m making it myself then I have total control over size. 


Large and bug-proof

Wants 3 and 4 are a bit harder. I wanted maximum ventilation when it’s hot, but good protection from the elements when cold and wet. I rarely pitch my tarp in the Desert but still want a barrier from the wind and dust. I needed a standalone bug shelter that could be pitched quickly. I could have added removable solid panels over the no-see-um netting, but that would have added unnecessary weight and faff. I chose to make my bivy from two equilateral triangles so that I could have different options on each side, and just rotate the bivy until I had the best option for the conditions. As I couldn't have a dedicated floor in the bivy I would need to use a separate groundsheet and, to prevent condensation, make the solid walls out of the most breathable materials. 

Bugsy can be a standalone Desert shelter, here pitched as a sand/windbreak
Rotate Bugsy and you have protection from drips
Rotate again for maximum ventilation
Want 5. Making it wearable was simple. A drawcord was added to seal the foot when used as a bivy and allow it to be opened up, so that it can be worn. The foot drawcord is now used to hold, and seal, the bivi around the waist. Wearing the bivy works best if you are wearing a hat and the upper bivy has an internal clip to secure it around the neck, which holds everything in place. I can now rest in a totally bug free environment for as long as I want. The windproof panel at the back offers lots of protection and add a surprising about of warmth on windy breaks. This bivy isn't meant to be worn when hiking and I don't think the mesh would hold up to shoulder straps for long.


Bug free breaks :-)
Bugsy offers loads of room to eat or read

Want 6. Depending on your shelter you can have the rear panel vertical or angled. Most shaped tarps need it angled so that it does not catch the sloping shelter walls. A vertical rear gives more space and is the preferred option if you have the choice.

Vertical ended bivy offering side/end wind protection
Sloping tarp end needs an angled bivy. Bugsy is offering side/end wind protection here.
The top picture shows a standard "A" frame pitch so a vertical ended bivy works well and gives maximum internal space. Because of the sloping end of the tarp in the bottom picture it’s not possible to have a vertical end, and it needs to be angled. This is easily done by added additional attachment points, at 15cm intervals, along the seams and threading the cord through them, so that they are bunched up as one. Depending on how many loops you thread through determines the angle of the bivy slope.


Standalone shelter offering sand/wind protection and showing the loops for changing the end panel angle.
Materials

I used the lightest nano-no-see-um mesh and tough, highly breathable but water resistant, Momentum 90 for the solid panels. The groundsheet is 1.2oz Cuben FibreThe bivi attaches to the groundsheet with mitten hooks (head end) and shock cord and mitten hooks (foot end). A half length No. 3 YKK zip is used for access. The groundsheet is fitted with linelocs to take up any slack and the groundsheet also converts into a rain skirt. Finished weight is 230g which is slightly more than my large sized enclosed bivy that it replaces. I'm happy with the weight for the extra protection and comfort it offers. 


Offering wind protection from the side/front