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Sub 1 lb. Intellectual Exercise


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  • #1436676
    Huzefa @ Blue Bolt Gear
    Spectator

    @huzefa

    Locale: Himalayas

    same here. This summer has been has been very hot -with temp crossing 90F during day.

    But today evening it rained for the first time. hooorraayy! I have already made hiking plans for the second and third weekend this month.

    #1436681
    Jay Wilkerson
    BPL Member

    @creachen

    Locale: East Bay

    Nice!!!! Put all that Intellectual brain power to use. Where do you backpack in India? I would like to check it out on good map. Thanks

    #1436685
    Huzefa @ Blue Bolt Gear
    Spectator

    @huzefa

    Locale: Himalayas

    Hi Jay.

    I hike in sahyadris – also known as western ghats. Its a pretty long range spanning six states. nearby trails are just 2 to 21/2hour train ride from my home. Fort, caves, temples, wild life, lovely water falls, all make it a fun exprience!

    #1436737
    mark henley
    Member

    @flash582

    And Tigers …. don't forget the Tigers.

    #1436823
    Huzefa @ Blue Bolt Gear
    Spectator

    @huzefa

    Locale: Himalayas

    lol

    Tigers exist only in sanctuaries and national parks. Trails are safe.

    But I did forget to mention that most trails are still unmolested and the views from the top make the effort worth it.

    #1436831
    Huzefa @ Blue Bolt Gear
    Spectator

    @huzefa

    Locale: Himalayas

    I bought a 3mm LED yesterday. Its 3v but the seller assured me that its alright to use 3.7v mobile battery. Well it works!

    While looking for 10mm superbright led online I also found some ultra violet LEDs. UV water purifier??

    Ultraviolet purification
    Ultraviolet (UV) light destroys DNA and thereby prevents microbes from reproducing. Without reproduction the microbes become far less dangerous. Germicidal UV light in the range of 240–290 nm acts on thymine, one of the four base nucleotides in DNA. When a germicidal UV photon is absorbed by a thymine molecule that is adjacent to another thymine within the DNA strand, a covalent bond or dimer between the molecules is created. This thymine dimer prevents enzymes from "reading" the DNA and copying it, thus neutering the microbe. Hydro-Photon introduced the portable UV water purifer, with the brand name SteriPEN. These UV water purifiers are lightweight and work very quickly.
    (wikipedia)

    The UV LED I had found earlier were 385-405 nm. So I googled 270nm and found company selling 250nm, 270nm, 280nm leds. They have these in flat and ball lens windows to produce Lambertian and focused emission, respectively. I think we need lambertian effect -light falling on it is scattered such that the apparent brightness of the surface to an observer is the same regardless of the observer's angle of view (wikipedia).

    I have never used UV purifier but I suspect it is as simple as placing a UV bulb on top of a 16oz bottle.

    #1436858
    Derek Goffin
    Member

    @derekoak

    Locale: North of England

    I think you would be better immersing the led to avoid reflection off the surface. The steripen would be so much better (lighter) with led technology. All the rest of the steripen is about containing the uv so it does not burn people and ensuring a reliable dose of UV in the field

    #1436862
    Roger Caffin
    BPL Member

    @rcaffin

    Locale: Wollemi & Kosciusko NPs, Europe

    Hi Huzefa

    > I bought a 3mm LED yesterday. Its 3v but the seller assured me that its alright to use 3.7v mobile battery. Well it works!
    Risky! Shortens the life of the LED a fair bit unless the battery voltage drops. If you can put a small resistor of 4.7 – 10 ohms in series that would be safe.

    > The UV LED I had found earlier were 385-405 nm.
    Very little germicidal properties. Pity, I agree.

    > I googled 270nm and found company selling 250nm, 270nm, 280nm leds.
    Yes, but check the price of the LED. Last time I looked they were about US$80 each.

    That said, I do agree with the idea. I can assure you that the Steripen company are impatiently awaiting the price on these LEDs to come down far enough to make a UV LED version commercially feasible. You will find this very desirable outcome mentioned some time ago in my review of the Steripen Adventurer here at BPL.

    > I suspect it is as simple as placing a UV bulb on top of a 16oz bottle.
    Emphatically NO (if I understand you correctly).
    The UV source must be IN the water, for two reasons. One is surface reflection. The other is consumer safety. Trust me, you do not want that UV-C light bouncing around into your eyes!

    Cheers

    #1437174
    Huzefa @ Blue Bolt Gear
    Spectator

    @huzefa

    Locale: Himalayas

    Thanks Roger, Derek.

    My internet connection wasnt working since last 3 days so couldnt reply earlier.

    I just finished reading 'Ultraviolet germicidal irradiation' at wikipedia and Steripen FAQ. Both interesting read. Now I understand something about UVC purification.

    I also checked pricelist at the manufacturer's website of that UV Led I was looking at. too expensive.

    Basically my idea is to multiuse lighter Li-ion batteries in UV purifier and LED flashlight.

    Roger, I think you are right. Its better to use a resistor.

    #1437191
    Richard D.
    BPL Member

    @legkohod

    Locale: Eastern Europe / Caucasus

    I have been going in a somewhat different direction with my ideas. I am finishing up my design of a 1.5 oz silnylon backpack. Next, I am going to look for lightweight silk to sew a narrow, body-fitted sack for sleeping in (probably 3 oz). My sleeping shelter will be an emergency blanket or emergency bivy. I can take a 2-person blanket that weighs 3 oz, trim it and glue it to itself to create a narrower bivy than the standard American Medical one, and use the extra material to create pockets on the outside of the bivy where dead leaves, pine needles and grass can be stuffed.

    For my sleeping pad I am looking at a 1/8 inch GG pad trimmed a bit narrower that would reach to my upper thighs and fold under itself for the shoulder area for 1/4 inch of padding there. Then I would make a 6 inch diameter disk out of some thicker padding in Glen Van Peski style for my hip bone or tailbone, depending on how I sleep. That will amount to 1.5 oz.

    In my theoretical calculations I am at about 13.5 oz, so that leaves me some spare weight to work with. I have considered getting some insulation material such as polarguard and sandwiching it between the silk bag and the emergency bivy (without sewing it to anything. Something like that might provide comfort down to 50 degrees or lower.

    #1437283
    Richard D.
    BPL Member

    @legkohod

    Locale: Eastern Europe / Caucasus

    Well, here is my finished silnylon backpack, at 1.58 oz. (guess what I spent the past 8 hours doing?)

    backpack view 1
    backpack view 2
    backpack view 3

    The pack is similar to Mark's (there's not a whole lot of variety at these weights), but some details may be different. For instance, there is no back pocket, and the entire body of the pack is made from one 75 x 75 cm piece of silnylon without cutting any of it. I have to get two toggle locks somewhere for it. It's sewn sloppily in places, but I think it'll hold 10 lbs. for a 3 or 4-nighter going with a sub 1 lb. baseweight.

    #1437325
    Huzefa @ Blue Bolt Gear
    Spectator

    @huzefa

    Locale: Himalayas

    looks really good. 1.58 oz for silnylon pack is cool.

    I am wondering if the convex back is a little unncomfortable? May be you can put some cord from the lid -back- to the bottom tightening which would give you a concave back frame.

    #1437327
    Richard D.
    BPL Member

    @legkohod

    Locale: Eastern Europe / Caucasus

    Thanks. What I can do is fold my sleeping pad rather than rolling it up. This will create a flatter and more comfortable surface against the back. If I did what you're saying, I think it would take a lot of tension to affect the back shape, and the pack seems pretty frail to me right now:) One thing I did do is make a hook at the top draw closure that hooks onto the string that you see going around the back, but in between the shoulder straps. This pulls the load closer to the shoulders and you get less load sag than you typically see with UL packs.

    #1437374
    mark henley
    Member

    @flash582

    Fantastic!

    Looks great.

    #1437953
    Huzefa @ Blue Bolt Gear
    Spectator

    @huzefa

    Locale: Himalayas

    I started a thread in the gear forum -'lightest technique to improve water taste?'. While thinking about different ideas people posted I remebered Bill's Cuben Amigo H2O Water Filter.

    Cuben Water Bag – 0.54oz
    Fittings – 0.176oz
    Hose (25") – 0.95oz
    Modified Hiker Pro Filter – 1.9oz


    Total Weight – 3.6oz

    my idea is to remove the filter instead fill activated carbon directly in the hoze and close the end with mesh. Also you dont need that long tubing.

    You collect the water in your bowl/cup. Once it fills the to the brim you UV purify it and pour the water into 2 liter platy bottle.

    Any thoughts on multiusing the cuben water bag? pack lid? rain hood? stuff sack? ??

    #1437954
    Huzefa @ Blue Bolt Gear
    Spectator

    @huzefa

    Locale: Himalayas

    I just finished reading reviews of Meridian Design mUV at backpackgeartest.org. This thing is amazing! 2.4 oz for an UV purifier + LED. Weight includes internal rechrageable battery which can be directly recharged by solar panel. I found some comments while searching the forum about people having some problem with the design. if the redesigned model is as good as it promises to be then its perfect!

    #1439382
    Aaron Sorensen
    BPL Member

    @awsorensen

    Locale: South of Forester Pass

    Hey Rick,
    Can you give us an explination of how you made the pack?

Viewing 17 posts - 126 through 142 (of 142 total)
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