Wednesday, 19 May 2010

DIY Hammcok Underquilt - Project

My First Homemade Winter Underquilt For My DD Hammock
(With added hindsight, there's lots of lessons learnt!)
I started off by purchasing a cheap large sleeping bag made by Hi-Gear, called Commando for £20. The only part of the sleeping bag I required was the two layers of Rip-Stock. In hindsight, I wish I'd purchased the Rip-Stock raw materials instead of taking apart a sleeping bag, because there was more work in the preperation than I antisipated!.. a lot more work!
The Sleeping bag first had to be taken apart at the seams without ripping the Rip-Stock. Then the cheap man made lining taken out! (This will be replaced with Hungerian Goose down, which is a lot lighter, and will reduce the overall pack size considerably)
Two tools I used to open up the sleeping bag were a small sharp knife, and a seam ripper.
I found one half of the Rip-Stock was in three peaces, which after removing the internal stuffing, and to be stitched back together again!
Next thing was to insert a foil survival blanket between the two layers. These can be purchased for about £1, and should add about +5c to the overall warmth of the underquilt, reflecting the heat back into the hammock.
Measuring out where the internal baffles will be with chalk first, allowed me to use these as guilds, as to where I would apply the glue for the survival blanket.
Chalked outline and baffles!
I glued the survival blacket to the Rip-Stock, along the internal baffle lines and outer edge with a wooden roller. I used a silicone based Bathroom sealant for the job. It is waterproof, mold resistant, has excellent qualities of adhesion and durability. It allows good flexibility along the seams, as it does not dry brittle, but has a more rubbery silicone finish.
After the survival blanket and one side of the Rip-Stock were glued, the other side of Rip-Stock was then attached by stitching all three layers together along the baffles and outerline. (apart from one end, which is left open for the goose down to be inserted at a later stage!)
All excess Rip-Stock was then trimmed off!
Not quite the finished shape, hindsight hits again!
To be the Winter warmer I wanted, I decided the overall length needed to be longer, to completely envelope my head and feet. So with the Rip-Stock I trimmed off, I painfully added to the ends. This took a lot of work to add on, but was worth it in the end!

My box of goodies arrive from Germany, supplied by

  • 100g of 860cuin Hungerian Goose Down
  • 4 Mini-Cordlocks with side loops
  • 2 Cannon Clips -fluorescent
  • 2 Cannon Clips - micro
  • 10 metres of 2mm black shock cord
  • 10 metres of 2mm Olive shock cord
  • 7 metres of 20mm strong Webbing - green
  • 4 40mm Micro Carabiners - Green
  • Total 64.10 Euro's with shipping.
Adding the Trimmings!
I decided to add a strong edge seam to the entire underquilt. This added extra weight, but gave me some reasurence that the quilt will last a lot longer to the strains and stresses of use!
I ironed a crease along the entire length of the webbing, to create an enveloping seam for the edging. (this will also give me a secure place to attach loops for the hanging of the underquilt!)
Stitching on the webbing edge!
Adding the shock cord to the foot and head end after the goose down was added to the baffles.
(yet another hindsight, 100g of goose down was not enough, it only fluffed up to about 1inch, so with much pain on the wallet, I purchased a 85% hungerian goose down 15% feather pillow from a local bedroom shop. It was cheeper than having to pay for the shipping costs again from Germany. I would estimate it had about 200g)
Finally, I added some orange webbing loops to the sides of the underquilt for the cord to pass through for the hanging of the quilt!
The Finished Product
(Note: Ends not tightened!)
  • Buy Rip-Stock as raw material rather than butcher a sleeping bag
  • Make square baffles to improve warmth
  • Get rid of webbing along outer edge to reduce weight
  • use larger cannon clips and 3mm shock cord for greater strength (reduced weight on these small items is probably not necessary compared with greater strength!)

Overall I am very pleased with the outcome. It is a large pack size, but this 'Is' a very thick mid-winter, full length underquilt, and should take me down to about -10c. With better hindsight for a future design, im sure I could reduce the overall size though.

Weight: 2lb 13oz (with 2 medium size caribiners, all cord and stuff sack) Suff Sack Size: 13in long by 6 1/2 wide (I used my thermarest stuff sack in the photo)


  1. Hey nice design!
    Just wondering if glueing the survival blanket to the ripstop was a good idea as it's not breathable and might leave the down moist over time. Did you experience any problems like that?

  2. A few people have asked this question. I've had the underquilt for almost a year now, and been out in all weathers. So far I've had no problems with any condensation building up, I think this is because the survival blanket is only on the outside, where the inside ripstock is still breathable!
    Cheers for your question.