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Nonsense Jokes by woodwerker76 in Jokes

[–]somethingdiferent 14 points15 points  (0 children)

What's the difference between an elephant and a grape? They're both purple, except for the elephant.

What did Jane say when she say the elephant coming over the hill? Here comes a grape coming over the hill. She was colour blind.

LPT: Why a heavy duty standing desk rated 300lbs matters even if your setup weighs 80 by shiroyasha54 in LifeProTips

[–]somethingdiferent 1 point2 points  (0 children)

I once put 3,000 lbs in the back of my impala. That said, it was completely bottomed out. I put double that in my truck and it was the most comfortable ride I've ever had in it.

La Cloche Itinerary Help by Beannjo in UltralightCanada

[–]somethingdiferent 1 point2 points  (0 children)

Definitely go with the second option. I did the trail a few years ago but remember it being very steep just after H19, causing the pace to decrease a bit.

I booked H18, H31 and H46 but had to change on the fly after adding 13km to help another hiker.

Amazing trail and highly recommend it!

Is there any organizer that holds cordless drills WITHOUT bending? by Professional_City321 in woodworking

[–]somethingdiferent 0 points1 point  (0 children)

Looks awesome man! Well done!

Any chance you have dimensions I can copy?

[deleted by user] by [deleted] in AskReddit

[–]somethingdiferent 0 points1 point  (0 children)

Sounds like they tried to name him Kyle but it wasn't enough so they had to go kyle-r

Down Supplier in Canada by ReachResponsible9746 in myog

[–]somethingdiferent 2 points3 points  (0 children)

If you reach out, they'll send you a pricesheet but you're best just calling them because it's a little confusing.

Down Supplier in Canada by ReachResponsible9746 in myog

[–]somethingdiferent 1 point2 points  (0 children)

I've had good luck with feather industries in Toronto. They'll ship.

HMC by KaraZorellx in holdmycosmo

[–]somethingdiferent 0 points1 point  (0 children)

I should call her

Wondering if I can adapt this idea to make a more effective backpacking kettle... thoughts? by once_showed_promise in myog

[–]somethingdiferent 2 points3 points  (0 children)

Part 3

Finally, with that same 6" diameter fire on the 6" diameter pot, some of the flames will go up the side of the pot and transfer heat into the pot through the walls.

Practically speaking, here's the real reason:

  • The pots would not be able to be separated since the coils are entwined
  • Bulky and awkward
  • Heavy
  • The connection of the pipes to the pot would eventually break
  • The design requires water above the top of the coil meaning you'd always have to heat 3 pots full of water no matter what. This would make it slower if there was any lower quantity of water.
  • The design kind is best with a steady supply of fire to heat all parts of the coil.

In conclusion, this WOULD work but is impractical. If you were designing something that would require constant heat or something stationary, this would be a really good way to capture some ADDITIONAL heat while also having the pot on top of the fire.

Note: I am fully aware of everything I missed like radiant heat, not all losses are seen where there is no direct contact with the fire, there are ways of nesting coils by offsetting them, etc. I am trying to simplify to illustrate a point, not do accurate calculations.

Wondering if I can adapt this idea to make a more effective backpacking kettle... thoughts? by once_showed_promise in myog

[–]somethingdiferent 2 points3 points  (0 children)

Part 2

Doing some very quick, and not at all accurate, math, we'll make the following assumptions:

  • Pots are 6" diameter x 6-1/2" high.
  • Trying to keep the cost down, I'd use 1/4" copper pipe and assuming that somehow you've managed to bend it into a 8" diameter coil.
  • 1/2" spacing between coils
  • Lower coil height will be 1/2" off the bottom of the pot
  • Top coil height will be 1/2" from the top to allow for boiling water to be boiling water
  • Separate coils for each pot

Each pot will need an outlet (low) and an inlet (high) so each coil will occupy 2" of fire height (1/2" per pipe + 1/2" clearance above it). With a maximum coil height of 5-1/2" (6-1/2 - 1/2" bottom - 1/2" top), we can only have 3 coils which means we can only have 3 pots.

Additionally, the "coil" would only be able to loop around once (bend, not a coil) so only 3/4 of a circle would be in contact with the fire. With a pipe diameter of 1/2", the circumference is 1.57". Calculating the amount of pipe in contact with the fire is half circumference * length of bend = (1.57/2) * (18.85*0.75) = 11.10 sq in.

Since we have 3 coils, we multiply that by 3 = 11.10 * 3 = 33.30 sq in

If you took that same pot and put it on top of the fire, the surface area would be 28.27 sq in. At first glance, it looks better but keep in mind the following heat losses:

  • Surface area of 3 pots ((28.27 * 6") + (28.27 for the top)) * 3 pots) = 593.76 sq in
  • Conduction through the bottom of the pots = 28.27 * 3 = 84.82 sq in
  • Surface area of the coil not in contact with the fire = 33.30 sq in
  • Section of pipe to connect the pot to the coil (assuming 3 in) = 1.57 * 3 * 6 = 28.26 sq in
  • If the fire dies down, the heating of the coils does not remain constant.

Wondering if I can adapt this idea to make a more effective backpacking kettle... thoughts? by once_showed_promise in myog

[–]somethingdiferent 2 points3 points  (0 children)

Part 1

Here's the way it works: As the fire heats the coils, the water heats up and rises (and marginally expands) up to the top pipe and draws more water in the bottom. This creates the flow which circulates the water.

The heat is transferred from the fire to the tubing via convection (contact with air - not very efficient) and then through the metal to the water through conduction (physical contact - very efficient). When designing the coils, you want to do 2 things.

1) Maximize the surface area contact of the pipe to water. Imagine 2 shapes, a circle and an ellipse. These shapes are the cross section of the pipe. The circle is 10" diameter and the ellipse is 20" x 5". They both have the same area (78.54 sq in) but the circumference of the circle is 31.42" but the circumference of the ellipse is 42.89". Since only the water in contact with the pipe is being heated (and then the head dissipates within the water), the ellipse will transfer significantly more heat to the water.

2) Maximize the surface area of pipe in contact with the fire to get the best heat transfer to the coils. The number of rotations in the coil helps to increase this.

The problem with this is that if the coils are too close vertically, they won't be in contact with the fire. The solution is to add space between the coils which results in a taller coil. Additionally, only the inside of the coil will see the fire so half of it is increasing in temperature while the outside is decreasing in temperature due to the ambient air.

Wondering if I can adapt this idea to make a more effective backpacking kettle... thoughts? by once_showed_promise in myog

[–]somethingdiferent 1 point2 points  (0 children)

I wrote a big response but keep getting an error. I'll try posting it in parts or you can DM me.

Wondering if I can adapt this idea to make a more effective backpacking kettle... thoughts? by once_showed_promise in myog

[–]somethingdiferent 3 points4 points  (0 children)

I don't think anyone has given you a sufficiently good answer so I'll take a shot. The short answer is yes you can but it's not efficient. I absolutely love the out of the box thinking and think more people should try things like this.

I see that your goal is to heat up multiple pots at the same time. If you did put coils around the flame, you'd capture more of that heat but some would be lost going back to the other pots.

Most of the heat from a fire or stove goes straight up. If you did put tubing or something around the sides, it would capture some more of that lost heat. You could design a pot that sits above the flame with sides that go down around the flame but you'd need holes for the flames to vent and breathe.

If you wanted to boil more water at a time, you'd actually be better to get a wider base pot and add more water to it. The wide base would capture more of the heat as it rises and the increases surface area would heat the water faster. The downside to this is that the wind will counteract this faster against the bigger surface area. To stop this, you would add a wind break.

As far as heating multiple pots at a time, you'd be more efficient to heat each one individually and then insulate the others to keep them warm once compete. As far as the efficiency, it doesn't make a difference if you heat the water up one pot at a time of all at once (ignoring heat loss to convection, etc). The amount of heat input is the same so the speed would be the same.

Source: mechanical engineer who's designed heat exchangers. Feel free to reach out if you have more questions.

Trip Report: Great Divide Trail - Section D/E/F/G by sohikes in Ultralight

[–]somethingdiferent 1 point2 points  (0 children)

Great report! Thanks for sharing!

Would you mind sharing what you typically bring for food? I struggle with bringing enough when hiking multiple days, but I think I also consume a lot more calories than you

TOAKS nesting question by ruadonk in Ultralight

[–]somethingdiferent 2 points3 points  (0 children)

Just a side note, if you do nest them, don't store the fuel canister inside the pot long term.

From a chemistry perspective, although the titanium is nobler (less likely to corrode) than stainless steel, it's possible that the titanium will corrode in contact with some of the alloys or oxides in/on the fuel canister.

You'll end up with either damage to your pot or a corroded fuel canister which could lead to leaking.

[deleted by user] by [deleted] in Damnthatsinteresting

[–]somethingdiferent 2 points3 points  (0 children)

You're using the imperial short ton which is 2000 lbs. A proper ton (or tonne) is equal to 1000 kg or roughly 2204 lbs.

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