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I think it would actually be quite difficult to start a fire with this. Speaking as a former boy scout who had to build a fire with a magnifying glass for wilde

by ythn 9y ago

I think it would actually be quite difficult to start a fire with this. Speaking as a former boy scout who had to build a fire with a magnifying glass for wilderness survival merit badge - it's really easy get smoke, it's quite difficult to get a flame. The article claims that he "set a piece of newspaper on fire" using the bowl, but after watching the video I just saw some smoldering paper - no flames. I'm betting the grape stem just smoldered a bit as well. You have to have very good airflow with dry, fine tinder in order to start a fire with a magnifying glass or parabolic mirror... unless of course you build a lens or mirror of monstrous proportions.

dekhn 9y ago
I can set a piece of cardboard on fire with visible flames in a few seconds. I carry a small fresnel lens, https://www.amazon.com/3-Pack-Credit-Card-Pocket-Fresnel/dp/B00NWMUK0I https://www.amazon.com/3-Pack-Credit-Card-Pocket-Fresnel/dp/...
- ythn 9y ago
  I still maintain that it is much more difficult to start a fire with a lens or mirror than people seem to think. Post a video of using your fresnel lens on different material types (paper, cardboard, wood, pine needles) and see how quickly you can get a visible flame. I'm betting you won't be able to easily get a visible flame on most materials you try.
  - cr0sh 9y ago
    > I still maintain that it is much more difficult to start a fire with a lens or mirror than people seem to think. I'd have to agree with you. When I go hiking, I carry around 3 or 4 different kinds of "fire making" things, just in case I need them for any reason. I also practice with them on occasion to know what to do when I really need them. It isn't easy to start a fire from scratch. It takes a bit of work, a bit of knowledge, and a ton of patience and perseverance. If you don't have any of that, you'll have a hard road ahead of you. Even using good tinder plus magnesium bar shavings and a flint striker isn't as easy as you'd hope. In fact, it can be very frustrating. But once you get it going, it's very satisfying. This is why I also carry a Bic lighter, strike-anywhere matches (in a waterproof container), esbit tablets, and a fresnel lens - all as backup fire sources.
  - dekhn 9y ago
    it's not hard for me for any of these. But then, I build telescopes and microscopes in my spare time and so I'm quite familiar with getting a good focus.

by ythn 9y ago

dekhn 9y ago

I can set a piece of cardboard on fire with visible flames in a few seconds. I carry a small fresnel lens, https://www.amazon.com/3-Pack-Credit-Card-Pocket-Fresnel/dp/B00NWMUK0I https://www.amazon.com/3-Pack-Credit-Card-Pocket-Fresnel/dp/...

ythn 9y ago
I still maintain that it is much more difficult to start a fire with a lens or mirror than people seem to think. Post a video of using your fresnel lens on different material types (paper, cardboard, wood, pine needles) and see how quickly you can get a visible flame. I'm betting you won't be able to easily get a visible flame on most materials you try.
- cr0sh 9y ago
  > I still maintain that it is much more difficult to start a fire with a lens or mirror than people seem to think. I'd have to agree with you. When I go hiking, I carry around 3 or 4 different kinds of "fire making" things, just in case I need them for any reason. I also practice with them on occasion to know what to do when I really need them. It isn't easy to start a fire from scratch. It takes a bit of work, a bit of knowledge, and a ton of patience and perseverance. If you don't have any of that, you'll have a hard road ahead of you. Even using good tinder plus magnesium bar shavings and a flint striker isn't as easy as you'd hope. In fact, it can be very frustrating. But once you get it going, it's very satisfying. This is why I also carry a Bic lighter, strike-anywhere matches (in a waterproof container), esbit tablets, and a fresnel lens - all as backup fire sources.
- dekhn 9y ago
  it's not hard for me for any of these. But then, I build telescopes and microscopes in my spare time and so I'm quite familiar with getting a good focus.