Desktop version
A place to chat about gear and the philosphy of ultralight. Ultralight bushwalking or backpacking focuses on carrying the lightest and simplest kit. There is still a good focus on safety and skill.

Forum rules

Ultralight Bushwalking/backpacking is about more than just gear lists. Ultralight walkers carefully consider gear based on the environment they are entering, the weather forecast, their own skill, other people in the group. Gear and systems are tested and tweaked.
If you are new to this area then welcome - Please remember that although the same ultralight philosophy can be used in all environments that the specific gear and skill required will vary greatly. It is very dangerous to assume that you can just copy someone else's gear list, but you are encouraged to ask questions, learn and start reducing the pack weight and enjoying the freedom that comes.

Common words
Base pack backpacking the mass of the backpack and the gear inside - not including consumables such as food, water and fuel
light backpacking base weight less than 9.1kg
ultralight backpacking base weight less than 4.5kg
super-ultralight backpacking base weight less than 2.3kg
extreme-ultralight backpacking base weight less than 1.4kg
Post a reply

No cost,super easy mat inflating bag

Sun 04 Jan, 2015 9:18 am

This is to reduce the amount of moisture introduced inside your sleeping mat compared to inflating by mouth.
Essentially it is a DIY Instaflator/Schnozzle whatever...
You need :
1x large light plastic bag. (One of your friendly clothing-collecting charity will put one in your mail box).
1x heavy duty rubber band . (Your postman will drop it along his way).
1x piece of clear tape. (any tape really...)

Put a largish piece of tape onto the area where you want the mat valve to go through.
(black dot in my first photo)
Cut a somewhat round hole large enough for the valve ; it does not need to be tight.
Insert the open valve into the bag, put the rubber band around the plastic bag over the valve and inflate.
Image
Image
Image
The version in those photos is about 30g, folds down to a C batt size.

Re: No cost,super easy mat inflating bag

Sun 04 Jan, 2015 9:25 am

Nice one Franco.

Re: No cost,super easy mat inflating bag

Sun 04 Jan, 2015 10:33 am

Thank you.
It was meant to be posted in the Make Your Own forum but somehow I was here instead.

Re: No cost,super easy mat inflating bag

Tue 06 Jan, 2015 7:54 pm

I did see something similar on a Facebook group many months ago. Brilliant idea.

Re: No cost,super easy mat inflating bag

Tue 20 Jan, 2015 9:25 pm

No brainer. Nice one!

Re: No cost,super easy mat inflating bag

Wed 21 Jan, 2015 9:41 pm

Another idea for easy, dry air mat inflation:

http://theportablebackpack.blogspot.com.au

Go down to the saving weight by saving money entry.

Skibug

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 9:29 am

I usually use my pack liner, but just scrunch the mouth of it over the nozzle of the mat. This is pretty nifty though...

If you put the hole 20cm down from the top you could even still use the plastic bad as a waterproof sleeping bag cover.

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 10:28 am

Skibug,
I tried the balloon pump about 10 years or so ago.
Next door to where I worked there was a Magic Shop selling those pumps , several types.
The best compromise between size and performance was this , but still much larger , heavier , much slower as well of course more expensive, than just using a bag :

Image

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 11:08 am

Yours is a nice, simple and cheap solution Franco. I guess it saves your lungs but I do wonder though how real is the danger of mat deteriorating due to moisture from the breath?

I have a number of mats and have always inflated them by mouth without any problems but I would be interested to hear if others had mats fails as a result.

Interestingly I just bought the latest Sea to Summit mat which guarantees that it is safe to inflate by mouth due to the anti microbial sealants they use.

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 11:28 am

I don't use that bag or the Instaflator or the pump , just my mouth with the Thermarests mats.
However if I did not have a built in pump in my Exped, I would.

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 11:45 am

Well that does not address the question Franco. Why not use your mouth on the Exped? Is it a fact breath will deteriorate it or just perception? Are you just erring on the side of caution? Keen to know because I have a Neoair which takes a lot of breath to inflate and I have not had success with the bag inflators.

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 12:04 pm

It is one of those things that I don't personally lose sleep over it.
It just makes sense to me that inflating with my moisture laden breath it could affect down, if it really does or not it honestly isn't important to me .
The reason I posted this simple bag thing is for people that also either are cautious or find it difficult/tedious to blow up their mats particularly the thick type.
Takes me over 20 breaths to blow up my Neo Air but only 3 bags of air , still as mentioned I can't be bothered taking that balloon thingo with me.

Anyway for you , from Exped :
We strongly advise against inflation by mouth as this can lead to the accumulation of moisture inside your mat and a reduction of insulating efficiency.

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 12:36 pm

Fair enough. I have heard the warnings often enough but never any concrete evidence as to whether it was a actual problem rather than an urban myth.

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 1:34 pm

I am a skeptic so typically I can smell a rat particularly when it smells fishy...
( OK , I'll stop now)
Seriously the theory (moisture inside causing bacteria build up) sound correct to me and I do know that moisture does collect inside, just ask someone that has a translucent mat (like the Exped UL or Big Agnes Clear)

Image

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 1:54 pm

No doubt moisture gets in from breath but it will also get in from air in general - meaning from an inflation bag. Compressors are notorious for trapping water. I guess the question is, does it matter. Is the smelly old air from your breath (and moisture contained therein) any worse that moisture from air in general? I guess your breath is a fair bit warmer and contains more bacteria.

Maybe gargle a little Listerine before you blow up your mattress just to be safe!

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 2:50 pm

Listerine is a single use item, single malt whisky is multi purpose.

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 3:00 pm

I suspect there's a reason that Xtherms are supplied with a pump sack.

The mat also gets heavier with moisture inside and who knows what bacteria you be releasing into the air every time you deflate the mat.
A big pump sack is also faster than blowing it up by mouth.

The problem is that breath air is at ~36°C and fully saturated with water. As it cools in the mat water condenses out of the air and into the mat.

With a compressor it's more about the changing pressure. If you halve the volume of a set amount of air at 50%RH, you double the pressure. Compressing it will warm it up slightly but by the time it reaches it's original temp it will now be at ~100%RH. Compressing it any more will lead to condensation. Ditto for cooling it.

Similar principles; neither change the fact that moisture is't great inside a mat. It probably degrades the insulation and increases thermal conductivity even in mat that have been designed to not fail if they get wet.

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 3:05 pm

Franco wrote:Listerine is a single use item, single malt whisky is multi purpose.


I'm sensing some disparity in our salaries!

Re: No cost,super easy mat inflating bag

Thu 22 Jan, 2015 4:25 pm

OK ,I'll settle for what I can afford , bottom shelf brandy...

Re: No cost,super easy mat inflating bag

Thu 19 Feb, 2015 10:05 am

Empty wrote:I have a number of mats and have always inflated them by mouth without any problems but I would be interested to hear if others had mats fails as a result.

My Mountain Designs 3/4 length self inflating mat recently started to fail. The outer skin has started to separate from the inner foam at the top near the neck and I now have growing bulge that is spreading rapidly.

Normally, I unpack it, let it inflate itself for a few minutes, then add a few puffs from my mouth to get the pressure up a bit more.

I'm not 100% sure if the failure is due to condensation from my breath causing the foam to deteriorate, or if I over-inflated it and took it 'over the limit'. I'll cut it open to have a closer look.

I've gotten almost 6 years out of it and it was a great price, so I can't whinge too much.

Re: No cost,super easy mat inflating bag

Thu 19 Feb, 2015 10:39 am

Sorry to hear about your growing bulge :shock:

I am guessing it is not the best practise but am inclined not to be too worried. Even a $300 mat over 6 years is only 50 bucks a year which is a fair bit cheaper than a motel room.

Re: No cost,super easy mat inflating bag

Thu 19 Feb, 2015 12:58 pm

Empty wrote:Even a $300 mat over 6 years is only 50 bucks a year which is a fair bit cheaper than a motel room.


Well, the mat was a lot cheaper than that. It is currently on sale for $60 http://www.mountaindesigns.com/store/eq ... eeping-mat

That's $10 a year! Bargain.

Re: No cost,super easy mat inflating bag

Thu 19 Feb, 2015 2:09 pm

Since I got a large neo-air xlite I use one of the little grey battery pumps. Works well. 30g with no batteries that can be swapped with head torch.


Ride On

Re: No cost,super easy mat inflating bag

Thu 19 Feb, 2015 8:27 pm

I am not saying that inflating by mouth doesn't put moisture into the mat but I have an original Thermorest from the early 80's which I used exclusively for 20 years. I once used it for six months straight inflating and deflating every third night on average. It is still working fine. Moisture and bacterial/fungal growth have had no effect. But it is a Thermorest and they built them tough.

Gordon

Re: No cost,super easy mat inflating bag

Wed 04 Mar, 2015 8:01 am

I shot a video on how to make it (sort of..) and how it works including how not to do it...
here it is :
https://www.youtube.com/watch?v=nux8bZ- ... ex5BMVK4vw
[youtube]nux8bZ-bJV8&list=UU0PuLUKvG7Fxxex5BMVK4vw[/youtube]
I have a low res version too for slower connections.
This was an excuse to try out my new video camera and the endless compression (quality settings) possibilities...

Re: No cost,super easy mat inflating bag

Wed 04 Mar, 2015 8:18 am

I think the moisture issue can be remediated by proper storage, that is leaving it with the valve opened and in the fulled expanded condition whenever it isn't being used. And I think I'm going to get one of those battery operated pumps, my ancient lungs seem to have lost the capacity they used to have; they also have a secondary use in blowing air into a reluctant camp fire I think
Post a reply