Polar Bear Tubes

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About: I'm just a guy that likes to fish, hunt, and be outdoors. Hope you like my ibles.

Do you go fishing or camping. Then this project is for you.

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Step 1: Materials

1. 2" PVC pipe

2. 2" PVC pipe cap

3. PVC Cleaner

4. PVC Cement

Step 2: Cleaning

Clean the inside of the cap and the outside of your pipe. Attach the cap to the pipe with some PVC cement.

Step 3: Filling

Fill the pipe halfway up with water. Then attach the other cap to the other end of the pipe and let it dry for 5 minutes.

Step 4: Freeze

After the cement drys put in the freezer until frozen then you're good.

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21 Discussions

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waltbosz

3 years ago on Introduction

This ible came from http://www.sheltonproducts.com/Coolertips.html , which is a site run by a guy named Bill Shelton. His intention for the tubes is as a substitute for ice in your fishing cooler. I suppose it may work to keep your drinks cool also.

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Jack A Lopezwaltbosz

Reply 2 months ago

Hey, nice find! It looks to me like this 'ible is a bad copy of that web page,

http://www.sheltonproducts.com/Coolertips.html

appropriating without attribution many parts of that page, including: the main image of the finished tubes inside an ice chest, with little polar bear images pasted to each tube, and also the name, "Polar Bear Tubes."

That page also answers some of the questions in the comments here, regarding the number for the max fill volume. Currently (2019) that page recommends a water fill volume of not more than 88% of the interior volume of the pipe.

Although if I use the Internet Archive's Wayback machine to look at archived volumes of this page, the earliest archived version (2006) of that page said 90%, for the max fill volume.

https://web.archive.org/web/20060115030238/http://...

By the way, the density of water ice is about 0.917 g/cm^3, compared to the density of pure liquid water, 1.000 g/cm^3, at temperatures near water's normal melting point, 0 C. That is according to the data sidebar of the Wikipedia page for, "Ice"

https://en.wikipedia.org/wiki/Ice

So the expected volume change, for a mass of liquid water, freezing into ice, is (1.000)/(0.917) = 1.0905

In a simple analysis, for which the volume of the pipe is constant, and the water volume changes by this ratio (r = 1.0905 = constant) upon freezing, compressing the trapped air, the compression ratio for the trapped air is:

R = (initial air volume)/(final air volume) = (1-p)/(1-p*r)

where p is the fraction of the pipe's volume filled with water initially, and (1-p) is the volume fraction initially filled with air.

So that is a simple expression for the compression ratio R for the trapped air, as a function of p, the initial volume of the pipe filled with water.

The punchline to this joke, is that R increases asymptotically at at the point,

p = (1/r) = 0.917 = (density of ice)/(density of water)

In other words, (1-p*r) = 0 corresponds a point at which the air has been compressed into exactly zero volume, and the ratio between its initial and final volume is infinite.

Anyway, I am guessing this is the math behind the Bill Shelton's recommendation for a max water fill volume of 88%, which was previously recommended as 90%. Both those are less than this asymptotic value of 91.7%

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SteveR300

1 year ago

Wonder if you could use the stuff in the (blue) soft ice packs to increase the freezing temp and duration. Especially if you had one break on you. Frozen water bottles work as well and you have water to drink when they thaw. These might be good as a bottom of a cooler since they are more durable than most water bottles.

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zaakoc

2 years ago

I like it! Elegant, simple and effective.
Addon ideas:
Put scrap rebar or other dense metal, stones or sand in with fluid to dramatically increase it's thermal mass and therefor it's cooling capacity.
Alcohol would be useful in a prepper way.

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jo'dell1

3 years ago

ok um way to many negative comments on this it is actually a very great IBLE! Well Done. A few ideas

A.) instead of water you could use an inexpensive but high proof alcohol. or isoprofol(sp) the fluid would then stay liquid and you might have a fuel source if for some reason you needed to make a fire in a hurry.

B.) instead of PVC you could just use hose barbs and caps and use flexible tubing so that you could bend the ice pack into different shapes before freezing.

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lmason1

3 years ago

I've seen these elsewhere, filled to 90%. I'm sure someone has written the expansion size of water somewhere :)

Also saw some recommendation for salt water, as it apparently freezes lower and takes more energy to melt.

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travisma

3 years ago on Introduction

You can custom fit them to your ice chest so they wouldn't waste as much space.

The only disadvantage that I see, is there isn't as much mass? as a jug, so I would think they would melt faster/not last as long?

Also, if you fill them with a salt water mixture they should stay frozen longer.

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waltboszjkimball

Reply 3 years ago on Introduction

I think the advantage is that you can cut the tubes to custom fit your cooler.

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BIVS2000

4 years ago on Introduction

I like it - very makeable. But what is it's main purpose and what does it do better?

Thank you!

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gator235

4 years ago

Intruiging..... However, you didn't state the purpose of the device. What is the purpose?

3 replies
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NeightRgator235

Reply 4 years ago on Introduction

These are heavy sticks that you can use to defend yourself against a polar bear or grizzly bear attack.

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RustonReds99

4 years ago

If you liked this Project please vote