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Tim Marshall
(MarshLaw303) - MLife

Locale: Minnesota
thin & light insulation question on 07/19/2008 07:19:31 MDT Print View

I am a big man and in the summer i sleep very hot. I am looking for an insulation layer to give me just the most minimal amount of warmth.

I got rid of my XP 2.5 quilt-too hot in only 60*

I have some combat 2oz but can already tell from another bag i made that it will be too hot too.

I don't see any reason to try primaloft 1.8, i'm sure it will be too hot.

Is there a way i can get my hands of just 2 layers of scrim?

I just want this for my mid summer's trips where it doesn't even touch 60* at night.

I would just use a layer of nylon, but i do want a little air trapped between 2 layers to insulate me from any wind i catch under my tarp and give me that cozy feel of a quilt/blanket.

Any ideas?

Edited by MarshLaw303 on 07/19/2008 07:20:25 MDT.

Ulrika Dahlin
(ulrika) - F
thin & light insulation question on 07/19/2008 11:47:51 MDT Print View

There will be a primaloft 40g (1.2oz) avalible in August, but I don't know if anybody is going to sell it for MYOG...

Check this thread for more info:
http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=12296&disable_pagination=1

David Wills
(willspower3) - F
Re: thin & light insulation question on 07/19/2008 12:02:38 MDT Print View

100 weight fleece maybe- it would be a tad heavy, but seems to fit the bill. You could also try a layer of nylon with a layer of silk or coolmax sewn to it. 4oz microfiber feels great, but would weigh as much as a 2oz combat quilt.

Michael Mangold
(mkmangold) - F
Re: thin & light insulation question on 07/20/2008 00:06:02 MDT Print View

Tim: I have a cotton (yes, cotton) sleeping bag liner that I used to layer my 40 deg bag last winter. I got through a 7 degree night with the liner, bag, and regular clothes in February. Now, approaching the dog days of Wisconsin, the cotton liner works just fine at night and I don't sleep particularly hot.

Tim Marshall
(MarshLaw303) - MLife

Locale: Minnesota
Re: Re: thin & light insulation question on 07/20/2008 09:16:37 MDT Print View

maybe the primaloft 1.2 is worth a shot. I can't bring myself to take cotton. I have drilled into my students for years that cotton kills and i would feel like a big fat Judas. Fleece is probably a good option, however i don't think i could bring myself to carry a bag that wasn't as warm as one 3-4 oz lighter. I want to be comfortable when i am hot but i also want to keep it as light as i can.

I really would consider, if i knew how to obtain it, making a bag with 2 layers of scrim inside. I just don't know how to get my hands on that.

Do you think a local craft shop would have some ultra-thin polyester batting? I might check that option out.

Tim

John S.
(jshann) - F
Re: thin & light insulation question on 07/20/2008 16:33:08 MDT Print View

nm

Edited by jshann on 07/20/2008 16:34:50 MDT.

Colin Krusor
(ckrusor) - M

Locale: Northwest US
scrim/batting on 07/20/2008 19:26:05 MDT Print View

Tim,

You could try polypropylene row cover. I've used it for bug netting, sleeping bag baffles, and a handfull of other things. It comes as light as 0.3 oz/yd (you could use several layers). It's basically the same composition as Thinsulate (very fine, soft spunbonded fibers). I bought a big bolt of it online awhile ago and it came out to 13 cents a yard.

Tim Marshall
(MarshLaw303) - MLife

Locale: Minnesota
Re: scrim/batting on 07/20/2008 19:56:04 MDT Print View

hmm, i'll have to look into that. where can it be found? I am not familiar with what exactly it is.

Colin Krusor
(ckrusor) - M

Locale: Northwest US
row cover on 07/21/2008 10:38:04 MDT Print View

Just google Agribon, Covertan, Reemay, or "floating row cover." It comes in many different weights. The "Reemay" stuff tends to be heavier (about 0.6 oz minimum) and made of polyester, and the Agribon and Covertan are polypropylene. There are a large number of online suppliers, but most nurseries and garden centers carry it as well.

The polypropylene varieties are just tyvek, but a little fuzzier and much lighter in weight.

David Erekson
(finallyME) - F

Locale: Utah desert
thin & light insulation question on 07/21/2008 13:18:06 MDT Print View

I have a 65 degree bag from slumber jack ($45). I don't think it has any insulation, just two layers of fabric. You might want to try no insulation, just two layers of fabric.

Tim Marshall
(MarshLaw303) - MLife

Locale: Minnesota
Re: thin & light insulation question on 07/21/2008 16:03:50 MDT Print View

i may try that. I am planning a sewn through down bag. Before i baffle it and add down i will sleep under it to see what i think.

i will check out the row cover options too, sounds interesting. Will it be comfortable draped over me?

Rog Tallbloke
(tallbloke) - F

Locale: DON'T LOOK DOWN!!
Re: Re: thin & light insulation question on 07/21/2008 16:21:06 MDT Print View

Very nicely finished quilt you put on gear swap Tim, I'm surprised no-one snapped that up yet. I was fingering some of the very thin insulation referred to above which was wrapped round the statuary in Hampton Court in London in February. Seems like a good option.

Tim Marshall
(MarshLaw303) - MLife

Locale: Minnesota
Re: Re: Re: thin & light insulation question on 07/21/2008 20:16:39 MDT Print View

i'm surprised that quilt is still around too.

Are you talking about the row cover stuff? Any idea what weight you saw? I know it's a long shot.

Tim

Just got to thinking. If i use the row cover stuff will i need to stabilize it more than on the edges like i do with cliamshield? I guess i could use ray's yarn loops or sew it down on the inside layer only. i just don't like to do that, it doesn't look and feel as nice i think.

Edited by MarshLaw303 on 07/21/2008 20:28:19 MDT.

Aaron Sorensen
(awsorensen) - MLife

Locale: South of Forester Pass
Re: thin & light insulation question on 07/21/2008 20:47:42 MDT Print View

Hey Tim,
You should use the prequilt from Thru-hiker.
it has a double scrim and is exactly what you are looking for.

http://thru-hiker.com/materials/insulation.php

Tim Marshall
(MarshLaw303) - MLife

Locale: Minnesota
Re: Re: thin & light insulation question on 07/21/2008 20:55:55 MDT Print View

no it is much more than i want. I just want the scrim, not the scrim in addition to the insulation. I am looking for a bag for only the warmest sweaty nights.

Tim

Colin Krusor
(ckrusor) - M

Locale: Northwest US
thin, light insulation on 07/21/2008 22:35:27 MDT Print View

Tim,

I second Rog's compliments on your quilt. I was impressed when I saw it.

I found an old photo of a summer sleeping bag (with me in it) that I made using the row cover about four years ago. It was four layers (outside --> inside): aluminized PE (like heatsheets), 0.3 oz row cover, aluminized PE, and another layer of row cover on the inside, against my skin (it's soft). It was fragile but warm (even through some frost and light snow one night on a grass pile without a pad), and it rolled up to about the size of a heineken can.



Polypropylene has both the lowest density and the lowest solid thermal conductivity of any textile fiber, and it's water absorbtion is essentially zero (a little less than polyester and a lot less than nylon). Also, the very tiny fibers in spunbonded polypropylene (less than 1 denier) make for a lot of tiny air spaces, and excellent insulation for the weight. Tensile strength is poor, though, and I've found that it has to be replaced about every year.A nap in the Olympic Mountains

Tim Marshall
(MarshLaw303) - MLife

Locale: Minnesota
Re: thin, light insulation on 07/21/2008 22:56:04 MDT Print View

i'm going to have to give it a shot. This looks like the perfect option for me.

Aaron Sorensen
(awsorensen) - MLife

Locale: South of Forester Pass
Re: Re: thin, light insulation on 07/21/2008 23:14:40 MDT Print View

Tim,
I used this during a 10 adventure race in Utah.
It's right up your alley of what you're looking for and know stronger and lighter as well.

http://www.buckscountyoutfitters.com/store/product/32308/Adventure-Medical-Thermolite-Emergency-Bivy-Sack/

Franco Darioli
(Franco) - M

Locale: Melbourne
thin & light insulation question on 07/21/2008 23:15:35 MDT Print View

How about just two silk liners , one inside the other ?
Franco

Rog Tallbloke
(tallbloke) - F

Locale: DON'T LOOK DOWN!!
Re: thin & light insulation question on 07/22/2008 00:28:57 MDT Print View

Franco:
You'd need a knife to escape in the morning!

Colin:
I like the heat sheet idea. How was it bonded - spray glue?

Tim:
Don't know the weight, I was going to steal some off one of the statues but my girlfriend shooe'd me away :o)

Edited by tallbloke on 07/22/2008 00:34:02 MDT.