Solar Furnace/Forge/SDR with a Fresnel Lens

[SolarStar !aO5Mv7EC6. No.179639]

An ex-coworker gave me a super fuzzy rear projection TV. Inside I scored tons of components including 3 really nice 3.5" lens and a 28"x33" Fresnel lens. I just got around to making a wooden frame for the lens. The next step is to make a holder and stand for it so I can turn it on both axis. That way alignment, with the sun, will be perfect. However, I couldn't resist testing it out with the new frame.

I took a penny, painted it black on one side with a marker, and set it on a rock. I aligned the Fresnel lens with the sun and nearly vaporized the penny. Had the zinc not run away at an angle it would have vaporized it. the copper coating was vaporized. I also scarred the rock with it and it popped and chipped away in the heat. This thing lights wood on fire instantly and chars it to nothing. In order to even use this I have to wear a welding helmet and look through dark lens. Otherwise, it would blind me like a welder.

Video of the carnage, too bad you can't see anything for the massive blinding light,
>35.61MB - no audio
>DSCN9576-1.m4v
http://www.mediafire.com/?syf0x5e5oyrcl0a

I really would like to try melting small amounts of metal with this and casting something small.

[Anonymous No.179773]

get a breathing mask if you're going to be melting zinc. the stuff's horrible for metal poisoning.

if you start to feel like you've got a bad cold or the flu, get to a doctor fast.

[SolarStar !aO5Mv7EC6. No.179837]

I just completed the stand for this. It rotates on 2 axis. I'll be moving the center cross bar down lower and putting more corner braces for that too. It hinges on nails and all the wood is repurposed scrap 2x4s. It brings the focal point up to at least waist level and should make things lot easier.

>>179773
Thanks. My welding helmet has positive pressure ventilation so I could be in a room of smoke and not once breath it. So long as the intake is elsewhere, it is fine.

[Anonymous No.179869]

>179837
I really want to build something like that for my Fresnel, did you build it from a design or did you just throw it together?

[SolarStar !aO5Mv7EC6. No.179966]

>>179869
i just threw it together, but I recall something similar from a few years ago from someone's SDR. I've also seen a couple pics of Fresnel lenses with frames like that. I think I may add holes on the ends of the boards on the bottom. That way I can drive spikes into them and into the ground to make it more wind proof. I also want to install something for the hinges that allows my to set them with tension.

Here's a hot-to video,

>FRESNEL LENS STAND HOW TO MAKE YOUR OWN STAND
http://www.youtube.com/watch?v=vTkUyJ7OHPk

I used a single table saw to do all the cuts.

[Anonymous No.179984]

>>179966
awesome thanks.

[Anonymous No.180011]

Why isn't this thread bumping. I had to dig to page 5 to find it after posting.

[Anonymous No.180134]

How hot does this thing get, like what container could you even use to melt metal

[Anonymous No.180280]

>>180134
A ceramic crucible is was is normally used for melting metal in. To melt the zinc in pennies it needs to be at least 787.15 °F, the boiling point is, 1665 °F.

Here's a video of a Fresnel lens melting a pad lock,
http://www.youtube.com/watch?v=YoMjBkKOkPc

Melting a pile of pennies,
http://www.youtube.com/watch?v=GcL7s9aX494

Melting glass,
http://www.youtube.com/watch?v=_lG1GfKVoYE

Melting rocks,
http://www.youtube.com/watch?v=zCxJziNScUU

Melting steel,
http://www.youtube.com/watch?v=_5NyZCu2d_c

[Anonymous No.180283]

Here's a video of one made with plastic and water,
http://www.youtube.com/watch?v=eeSyHgO5fmQ

Best used around noon it seems.

[SolarStar !aO5Mv7EC6. No.180454]

I had time to test the stand and lens today by making breakfast. I fried sausage patties. Pics related.


Here's a video of it,
http://www.youtube.com/watch?v=dGhj3JHzEbU