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Turk
2005-03-10, 21:05
Hey hammock folks,
Being relatively new to hammock camping, perhaps some of you have found other solutions to this problem, or have built other inventions to combat this problem.

The problem: Your butt gets cold in a hammock because your sleeping bag is so compressed. The Sarge mentions this several times in his site, and it was based on some of Sgt Rocks comments that made me want to build this idea.

I call it the "Bummock". Basically it is a small down-filled pad, that velcros inside your sleeping bag to add a double layer to your down bag from your lower back to the back of your calves.


http://www.geocities.com/roleplayingt2t/bummock.JPG

The idea is, you velcro the pad in when you need it. And when you dont, you fold the padded flaps that are sewn into your sleeping bag over so you are not sleeping against the velcro strip.

It entails alot of sewing, but my sister is a good seamstress. Please tell me what you think of the idea. Particularly if you see anything about it that might not work, or is not practical, or if you do not think it will solve the problem at all.

Based on the feedback, I would like to come up with a final design before the weekend so I can get it sewn up and try it out.

wentworth
2005-03-10, 23:27
If the down filled pad was inside the hammock, it too would be compressed. It would work if you put it on the outsude of the hammock though. Or is this what you meant and wrote "inside" by mistake?

Lanthar
2005-03-11, 11:51
If the down filled pad was inside the hammock, it too would be compressed. It would work if you put it on the outsude of the hammock though. Or is this what you meant and wrote "inside" by mistake?
That's what I was about to say

deadeye
2005-03-11, 13:40
How 'bout filling it with open-cell foam instead of down. OC foam is light and fairly compressible for packing, but not as compressible as down so it would still provide the needed insulation, and in this application won't be in a position to soak up moisture.

Lanthar
2005-03-11, 16:09
How 'bout filling it with open-cell foam instead of down. OC foam is light and fairly compressible for packing, but not as compressible as down so it would still provide the needed insulation, and in this application won't be in a position to soak up moisture.

that would be better, but it still wouldn't be the greatest as it will still compress and lose a good bit of it's insulating properties. If you're using an insulation that relies on loft, it really needs to be on the outside of the hammock. if you are bound and determined to have it inside the hammock it needs to be noncompresible or be non dependent on loft for insulating properties (aka closed cell foam / evazote / bubble wrap insulation / etc)

deadeye
2005-03-11, 16:45
True that, Lanthar, and on further pondering, it's not usually my butt that gets cold in the hammock, 'cause I do have the closed-cell evazote pad already in there. The chill usually comes from around the shoulders where the typical 20" wide pad, which works great on solid ground, is not wide enough when wrapped in the hammock cocoon. It's still plenty cold up here, maybe I should go pitch the HH in the backyard and test some things in real winter...

Lanthar
2005-03-11, 18:09
you're probably losing heat from wind penetrating the fabric. try shoving a trash bag in there as a wind block.

Turk
2005-03-11, 18:18
Well you guys certainly seem versed on the subject. Perhaps I am approaching this whole thing in the wrong light.

Let me start again, before I go enlisting my sister for hours of sewing.

What should I be using to get some increased warmth in my hammock.

I've had trouble with pads because they slip around so much and by morning I always end up half off of them. Pads also start to get permanent creases in them after only a couple of nights. So allow me to ask the right questions here.

Is a pad the way to go? And if so, what is a really good pad to use? $$ no concern.

Is there some other prefered method? I am not necessarily looking for a project to 'make something'. I just had a feeling that there was nothing specific on the market and I would end up having to rig something up.

Share me your expertise and I shall be much appreciative.

wentworth
2005-03-11, 18:54
The best outside-insulation for the hammock seem to be the down filled coverings. For the Speer/open top type hammock, the down filled Peapod sleeping bag.
For the hennessy hammocks, the Jacks r better underquilts.
Neither of these options is cheap, but have both received good feedback. I have the Nest by jacks r better and am very happy with it.

SGT Rock
2005-03-11, 21:23
Go look at www.thru-hiker.com, they have the Canoe Blue hamock under quilt that is not multi-use like the JRB, but it is a little lighter.

deadeye
2005-03-11, 23:17
Every now and then, I try to slap some sense back into myself and say things like "hey, stupid, don't get so complicated" (I say that to myself, not to others). When I do that, I come up with things likethis:

1) My HH weighs 30-32 ounces, and is very comfortable, unmodified, in mild temps.

2) My Tarptent Squall weighs 30-32 ounces, and is very comfortable, unmodified, in all but the coldest temps of full-on New England winter.

3) In the coldest temps of full-on New England winter, weight of gear is almost a non-issue - keeping warm & dry is number one

4) Conclusion: to every season, there is a thing

blackdog
2005-03-12, 05:02
Is a pad the way to go? And if so, what is a really good pad to use? $$ no concern.
WARNING! The below link is not for the cash-strapped or for those of a conservative disposition.

If money's no object then go for an aerogel underquilt:
http://www.aerogel.com/footwear.htm

disclaimer: Hey! Somebody had to say it... ;)

Iceman
2005-03-13, 02:40
Blackdog, why did you do that to me? Now I have to save up and buy something made out of Aerogel. Thanks a bunch :biggrin: (cool link)

blackdog
2005-03-13, 06:13
Here's some more info about the material I'm talking about:
http://stardust.jpl.nasa.gov/photo/aerogel.html

This is as close as you can get to the emperors new clothes today. It's a material that's almost not there at all...

Aussie Nutter
2005-03-14, 02:40
Aint an underquilt just half a cut up sleeping bag hanging under the hammock so that your body cant compress the fill? and wouldnt half a sleeping bag compress and weigh similar to a foam pad.
What about half a cheap sleeping bag some string and some plastic to waterproof it?
Only one seam to resew to keep the fill in the bag and you can re-use the zipper so u can play with the amount of fill you require from the other half of the cut up bag. Sounds dumb? tell me so!

icedancer
2005-04-04, 15:19
Sorry, but you'll have to wait. I used their web request last week and got a nice reply saying that it will be some unspecified time before any products are available commercially. It sounded like "Dont' hold your breath" to me.

climber11
2005-04-04, 15:50
Hey all,

I just finished up making an Jardine inspired underquilt yesterday. I used sil nylon for the bottom, and 1.1 for the top, lightloft synthetic insulation 1.5". Total, all weighed in a stuff sac = 17oz. It was super easy to make, and I even made a head hole and collar in the middle for me to wear it as a poncho/vest thing during cold camp evenings. I got in it last night and it was sooooo warm! I am not going to use a pad anymore for the inside. Just seems silly to me due to their inherent uncomfort.

Also, note that my pad/reflector combonation was 20oz, so I saved some weight. compresion is down to about 8x8".

Scott

icedancer
2005-04-04, 16:09
Climber11, Care to share your design? I've been thinking about doing the same thing. How are you suspending it?

climber11
2005-04-04, 20:54
Ok, so start off with a suitable rectangle for your size. mine was about 48" by 60". The bottom was Sil-Ny, top-regular 1.1oz Ny. I then layed the 1.5" insulation, in my case lightloft, on top of both pieces of nylon and sewed them together ins. side up around th perimeter save about 12" on one end. This 12" was going to be velcro so I could add more insulation later if needed. After turning everything inside out, nylon in the right place, I sewed up the final seam, put tabs on the corners, and tied on shock cord. With my fiancee in the hammock, I simply looped it to the rain fly hook from both sides and test fit. Once I figured out where to take material out for a better fit, I cut away and Voila, underquilt success. I initially slit one end all the way to the middle like the Jack's R Better stuff, but decided this was a waste later on and sewed it back together. The head hole was really easy. I sewed it straight through all layers, cut, and shock corded it. I did end up putting a collar on it to help with wind, and to help seal the hole up tight. It works awesome so far.

I'll try to post some photos tomorrow.
Scott

climber11
2005-04-05, 12:30
Ok, here's my first try at photos.

Lanthar
2005-04-05, 13:05
nice, very nice

icedancer
2005-04-05, 15:30
Thanks! How important is it to do the fitting? What I see from Jacks R Better and other folks who have done under quilts is a basic rectangle, with maybe what appears to be a drawstring to tighten up the ends. I assume that the sides of the quilt snug up with the hammock as the ends are attached. Is it a problem having extra air space between the hammock and the quilt? If you do try to cut the quilt to fit, will simple curves like this be suffcient?

climber11
2005-04-05, 15:49
Fitting the quilt was pretty easy. I made the simple rectangle first. Had someone lay inside, and then gathered material with clothespins to help subtract the extra space. I paid less than $40 for the whole setup including the shock cord.
Scott

GregH
2005-04-05, 16:41
Was it difficult to sew the silnylon? How small does it roll up to? Do you have any guidance/tips you could share? Down to what temperature have you used it?
Your design looks great and is inspiring even me!

Rage in a Cage
2005-04-05, 18:00
Am I correct in assuming that the Liteloft comes in a sheet? Where did you buy the Liteloft? And one more question, Does it compress to reduce volume or does it roll up like a pad? I use a pad all the time but hate the volume issue.
I have a down bag that I no longer use and have been thinking about converting a piece of it into a under quilt and maybe using the remaining down for an over quilt. I just hate having to sew in baffles. I take that back, my wife hates sewing in baffles. :bawling:

NiteShiner
2005-04-05, 18:04
Then take a hint! :) My mom taught my ex more about sewing than she ever taught me. He was pretty good at it.

Rage in a Cage
2005-04-05, 19:21
My wife does the "sewing" so she doesn't have to go to the field and do the "sowing." :biggrin: Actually an Eskimo friend of hers does most of the sewing for me. :fisheye:

GregH
2005-04-05, 22:13
4) Conclusion: to every season, there is a thing

...turn, turn, turn. (with apologies to The Mamas and the Papas)

climber11
2005-04-06, 12:23
Howdy,

For what it's worth, my fiancee can't sew at all. I have learned through trial and error only within the last few weeks. It's really not all that difficult to sew the silnylon. As long as you go slow, pin your seams, use tape, or clothespins...things go fairly smooth. I give myself a 1" seam allowance so I have plenty of error room, and can then trim, or fold over. The lightloft was from Seattle Fabrics. I had never heard of it until I walked in and they showed it to me. It is at least as light as the 3D I used, but maybe a bit less dense. The compression is about 8" square, though I could go smaller with one of those ultra cool compression sacs. I am a bit afraid of those however. I did keep it in a sac for awhile, and then tested how fast it returned to shape. Pretty quick. Good luck!
Scott

Mutinousdoug
2005-04-06, 16:52
... I sewed up the final seam, put tabs on the corners, and tied on shock cord. With my fiancee in the hammock, I simply looped it to the rain fly hook from both sides and test fit. Once I figured out where to take material out for a better fit, I cut away and Voila, underquilt success.

Scott,
So if I understand your description and your pictures, you cut away only insulation once you'd determined where the excess was, and left the cover more or less a rectangle?
Then I assume you shock corded the ends, not the sides,(and neck hole) only. You say you tied on the shock cord... do you mean you ran it through the hem?
Great project incidently, and thanks for sharing.

climber11
2005-04-06, 19:20
I ended up sewing loops of webbing to the corners and stringing the cord from them. I may end up running a cord from side to side to tension the ends, but so far it's not been a problem. Thanks for all the inquiry!
Scott

Rage in a Cage
2005-04-06, 19:48
I realized, after reading futher, that I have heard of it before and had even considered using it in a couple projects. At least I think it is the same stuff, Check out the link and let me know.
http://cms.3m.com/cms/US/en/2-147/crzucFY/view.jhtml

climber11
2005-04-07, 12:36
Yup, that's the stuff. Looks like I did ok in my selection. Actually, that's all they had, and I got the end of the roll. If I remember correctly, it was less than ten dollars a yard.
Scott