Field report - HH overcover - it works

[kwpapke]

Also, I can't wait to see your results with the down jacket on top of the pad. It seems this would compress the down too much ( as oppose to placed in the UC), but maybe not!

It didn't get as cold last night as the weatherman predicted, but still 7F is colder than the prior night:

Clothing worn was almost the same except I did try a balaclava for a few hours, and found it too constricting & irritating. Also added heavy 2nd set of wool socks.

The Exped Multimat was unfolded, so only a single layer but it covered the entire Undercover. Fabric side was up.

Added: down jacket underneath torso & Garlington (stuffed with newspaper) under the legs. I know paper isn't practical in the field, but its what I had on-hand. Both of these were inserted above the Multimat and below the SS OCF pad making an insulation "sandwich".

Results: MUCH warmer on the bottom. I was toasty all night long. The only time my butt or legs would get cold was when I slept on my side in a fetal position causing those extremities to ride up over the sides of the Multimat. My feet were warmer, but still not optimal. Need some down booties or something. Quite a bit of frost on the inside of the Overcover in the morning. The unfolded Multimat does make it more difficult to get in/out of the entryway slit of the HH.

Conclusions: Billybob's fear of the down jacket compression appears not to be borne out in practice in this configuration. The OCF pad is held up off the jacket by the elastics. The Undercover/Multimat beneath present a large enough surface area and low enough tension to prevent compressing the down. The Garlington seemed to help quite a bit on the legs, but it was somewhat difficult to distinguish how much benefit came from the unfolded Multimat versus the Garlington.

Next up: all this is in preparation for a 4-day trip to the Superior Hiking Trail in northern Minnesota next week. I have some trepidation due to the sub-zero lows forecasted for Wednesday & Thursday. This trip may end up being shorter than planned...

--Kurt

[BillyBob58]

It didn't get as cold last night as the weatherman predicted, but still 7F is colder than the prior night:.................
The Exped Multimat was unfolded, so only a single layer but it covered the entire Undercover. Fabric side was up.

Added: down jacket underneath torso & Garlington (stuffed with newspaper) under the legs. I know paper isn't practical in the field, but its what I had on-hand. Both of these were inserted above the Multimat and below the SS OCF pad making an insulation "sandwich".

Results: MUCH warmer on the bottom.................
Conclusions: Billybob's fear of the down jacket compression appears not to be borne out in practice in this configuration. The OCF pad is held up off the jacket by the elastics. The Undercover/Multimat beneath present a large enough surface area and low enough tension to prevent compressing the down. The Garlington seemed to help quite a bit on the legs, but it was somewhat difficult to distinguish how much benefit came from the unfolded Multimat versus the Garlington.

Next up: all this is in preparation for a 4-day trip to the Superior Hiking Trail in northern Minnesota next week. I have some trepidation due to the sub-zero lows forecasted for Wednesday & Thursday. This trip may end up being shorter than planned...

--Kurt

Man oh man, keep up the good work and research, Kurt. You are starting to make me wonder why I left my SS for other options(well, one reason was to try top loading, No Net hammocks).

But please clarify a couple of things which I think I am confused about. You had said : "add in my new down jacket sandwiched between the OCF and Multimat". I was thinking you were on this multimat INSIDE the hammock, laying directly on it. So I took it therefore that you were going to try your down jacket ON TOP OF your OCF HH pad. Which is why I wondered if you would get too much down compression, since the down would be between your body weight and the "snug" fit of the OCF pad.

But instead, it seems that this multimat is used down in the UC? So actually your down jacket is also down in the UC, below the OCF pad and space blanket? In that case, I would not be worried about down compression.

But I am amazed to hear that you are using the multimat down in the UC ( if that is correct) and that it is working. The first night I ever used my SS, I froze. I latter found out one of the things I did wrong was place my pad in the UC, which caused a gap and loss of warm air. But maybe this multimat is flexible enough and light enough per square inch that it can be placed down in the UC without negative results. Apparently so.

I anxiously await to see what Minn. temp is too much for your SS!

[kwpapke]

I was thinking you were on this multimat INSIDE the hammock, laying directly on it. So I took it therefore that you were going to try your down jacket ON TOP OF your OCF HH pad. Which is why I wondered if you would get too much down compression, since the down would be between your body weight and the "snug" fit of the OCF pad.

But instead, it seems that this multimat is used down in the UC? So actually your down jacket is also down in the UC, below the OCF pad and space blanket? In that case, I would not be worried about down compression.

But I am amazed to hear that you are using the multimat down in the UC ( if that is correct) and that it is working. The first night I ever used my SS, I froze. I latter found out one of the things I did wrong was place my pad in the UC, which caused a gap and loss of warm air. But maybe this multimat is flexible enough and light enough per square inch that it can be placed down in the UC without negative results.

Sorry if I wasn't clear in my earlier posts. Indeed, the Muiltimat is placed in in the UC, I am not sleeping on it in my hammock. I gave up trying to sleep on a pad back in March when I first bought my HH for all the usual reasons.

Yes, all the insulation is in the UC. I sleep on the bare HH - well on the bottom of my mummy bag anyway. See my IR on the Multimat on BGT here:

http://www.backpackgeartest.org/revi...0Kurt%20Papke/

The pictures there might make it more clear.

I think what's happening here is if you try and use a stand-alone mat in the UC there just is not enough bulk to hold it in place and snug against the hammock bottom. With the SS pad + SB in place and snug against the hammock bottom, anything crammed in below that just adds to the insulating capability. With a puffy down jacket and Garlington between the OCF & the Multimat held up by the UC, the airspace is pretty well filled so the Multimat pad can hold the warm air in.

There are real downsides to this whole approach. Setup becomes more difficult the more stuff you put into the UC: SB, OCF, Multimat, jacket, kitchen sink... However, what I am trying to do is maximize multitasking of the gear: the Multimat will also function as a sit-pad, the jacket is obvious, the SB can be used for emergencies, etc. The only item that does not multitask is the SS OCF pad.

-Kurt

[hikingjer]

kwpapke:

This is great stuff! Keep it coming.

I just bought a HH overcover to add to the OCF & UC for cold weather but wonder how it'll work at temps about 15 - 20 degrees in high humidity like 80% - 99%. Inside the hammock I plan on using a Speer SPE with foam pad wing inserts and a Big Agnes air mattress with a 0 degree rated down bag and possibly a Outdoor Research Winter Sack bag cover. I want to use this set-up on a cross country ski-packing trip in the North Cascades. Sleeping above the snow seems so much more reasonable than sleeping on or in it, like in a snow trench. A pee bottle will come in particularly useful for long late winter nights in a hammock.

Are you using the stock HH tarp on these experiments? Or, are you using a larger tarp that blocks drafts and loss of radiant heat?

[kwpapke]

I just bought a HH overcover to add to the OCF & UC for cold weather but wonder how it'll work at temps about 15 - 20 degrees in high humidity like 80% - 99%.
...snip...
Are you using the stock HH tarp on these experiments? Or, are you using a larger tarp that blocks drafts and loss of radiant heat?

It should do fine in the high humidity if its below freezing. Look at the stats for my prior night - humidity was near 100%.

Stock tarp - all I'm looking for is something to keep the snow off. For sleeping, I dunno how much more a larger tarp would help my configuration: the OC, UC, etc. takes care of most of the drafts. The major reason for a larger tarp would be for cooking & socializing.

I *do* pitch my tarp pretty steeply in the winter, i.e. pretty snug to the OC. Keeps the snow from building up, and it can't hurt when it comes to wind impact.

--Kurt

[hikingjer]

You used the overcover in 100%, dewpoint reached and survived. That's good news.

Once the days are longer, like in mid-February, I want to go snow camping in a hammock. To be on the safe side I think I'll use the Equinox 8' x 10' silnylon tarp with the HH rig for extra coverage. First trip out will be within walking distance of the car. I plan on digging some snow out and building snow walls around the hammock & tarp to block wind. This will happen anyway for a kitchen and if tent camping. I will report back to this forum on any snow camping trips during XC ski trips and tell you all how it went, what worked and what didn't.

Your reports on using hammocks in MN cold weather are inspiring. Thanks again.

[lazarus]

anybody ever use the stock HH overcover on a top loading hammock? my favorite hammock these days is an ultralight travel hammock with added structural ridge line... i'm pretty short, and it is comfortable for me despite the relatively short length -- and i love its weight. seems like the overcover would work if i just hung a rock or something from the side pull out points and let it drape over the hammock. I've got to say that i've only had positive experiences using the overcover with an HH hammock, but i'm looking for alternatives... just ordered a torso length uq from the Jacks... with the ultralight hammock, an HH overcover and a stock HH tarp i'm hoping to be sneaking up on a comfortable ultralight setup... I do figure there are times I'd add some ccf to the mix. What do you think about the overcover on other hammocks?

[kwpapke]

Just got back from 3 days/2 nights up on the SHT. About 0F Monday night, -2F Tuesday night. Plenty warm both nights, though got a little chill on Wednesday morning I think because my 0F sleeping bag started to get significant ice crystals forming beneath the shell.

Monday night's campsite:


Tuesday morning's temperature:


Insulation was little changed - from the bottom up: SS Undercover, Exped Multimat, Montbell Permafrost down jacket under my torso, SS OCF pad, space blanket. I was much warmer. The big change was I reversed the Exped Multimat and had the EVA CCF side up with the nylon down. My intent was to keep the down jacket from moving around as the CCF foam is stickier than the slippery nylon side, but subjectively it seemed a lot warmer too.

Lots of frozen condensate on the mesh netting and Overcover on Wednesday morning. At very cold temperatures the Overcover almost makes the HH into a single-walled tent. Picture from Weds morning:


I'd say that's getting down there in temperatures w/o an UQ...

--Kurt

[BillyBob58]

It sounds like you may have found a useful add on to the SS UC with the Exped Multimat. Does it have any other uses for you besides in the UC? Sit pad, that sort of thing?

Have you tried the SS both with and without the Multimat in the UC? If so, have you formed an opinion about how much the Multimat helps?

BTW, once again, incredible results! Have you thought about VB clothing to help with those ice crystals in your bag?

[warbonnetguy]

hey all, i'm about to start messing with designing an overcover for the blackbird, i was wondering how large the vent is. it's right above your face correct?