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Solar powered wood burning

  1. Aug 8, 2007 #1
    Hi, I'm new to this forum, and from what I've seen so far, there are some very intelligent people posting here, and I'm hoping someone will have an answer for me.

    It's a two part question basically boiling down to one point.

    I've recently become involved in wood burning as a hobby, particularly with using a small magnifying glass (2x mag). I've developed a potential application for more precise wood burning this way, but I don't want to have to rely on the weather to be able to do any work, ie: a nice sunny day. Sadly, my limited experience with light or optics has me baffled.

    First part is...what is the wavelength of sunlight that when focused is responsible for generating enough heat to burn, or is it a full spectrum kind of thing?

    And the second part is....is it possible to generate and focus enough light artificially (of whatever part of the spectrum) to burn without having to wait for a nice sunny day?

  2. jcsd
  3. Aug 8, 2007 #2


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    It's basically the power not the wavelength.

    As to what you would use for a source, other than an industrial CO2 laser, I'm not sure. It would be difficult to put enough power into something you could easily move around - it would probably have to be fed down a fibre into the tool used to draw the pattern.
    You would probably be better looking at some sort of hot wire type device.
  4. Aug 8, 2007 #3


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    Welcome to PF, Helios.
    I agree with Mgb. By the time you get finished sucking up enough electricity to run a major light-producing device (be it an arc lamp or a laser), then use it to burn your pattern, you'll find that it isn't worth the effort and expense. Just use a regular soldering iron type burning tool when the sun's not co-operating and your magnifying glass when it is.
  5. Aug 9, 2007 #4
    That's what I was afraid of. I was hoping for a fully non contact method, and as cheap as possible, but it looks like I'll have to go the laser route.

    Thanks guys.
  6. Aug 9, 2007 #5


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    You're quite welcome. Be aware, however, that it takes a pretty powerful laser to burn things. While the effect upon the target is similar, the method of delivery is different. If you go that route, make sure that you take all necessary safety precautions, including the use of goggles. Even reflected laser light can cause severe eye damage. In some jurisdictions, you even need a special license to own and operate that class of laser.
    I appreciate your desire to do things 'hands off', but I'm not exactly sure what your parameters for that are. I have an alternate suggestion, but it might involve too much physical contact for your liking. I'm thinking of you painting your design on the wood with an exothermic chemical (something like thermite) that you can then activate with a lower powered laser.
    On the other hand, and much simpler and cheaper, you could do it with a pin-point torch similar the the cigarette lighter than W bought me. You can solder with the bloody thing, but the flame point is about the size of a regular pencil.
  7. Aug 9, 2007 #6
    glycerin and potassium permanganate combust nicely by themselves
    have you tried using elliptical mirrors? they might be more effective and cheaper
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