OLcontest, modified light: 20cm fresnel lens thrower

Flashlight Modding and DIY Parts
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I bought it a few years ago actually, on aliexpress. They are cheap (under 10 dollar for a 20cm diameter lens) and pretty good, here is a link, I expect it to be the same quality as the ones I got. I chose 200mm focal length as a compromise between the amount of light catched by the lens, and image quality (a very short focal length lens will catch/transmit a large percentage of the light but also show a lot of image distortion at the edges which will negatively affect the beam and throw).

https://m.aliexpress.com/item/32650652778.html?spm=a2g0n.productlist.0.0.19d315a3EZSPBz&browser_id=66b1ef171b05438fb64eff5ede7df8ad&aff_trace_key=8a9fcaee55ca4f97ad04c20e01d01302-1603223217706-05977-UneMJZVf&aff_platform=msite&m_page_id=uwt5f3ysax4carj3175b3e1b8271a9c5879ed5cc9b&gclid=&*imgsrc*=ae01.alicdn.com%2Fkf%2FHdaa45cc53f114786a1a4c40ca2433fd0A.jpg_640x640Q90.jpg\_.webp

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Thanks.

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That is amazing, very well done djozz :+1:
Now that is thinking outside the box ! I never thought a Fresnel lens could do that !
You could do a Batman thingy in the clouds too.
No doubt this years competition is heating up :smiling_imp:
BLF has other forums beat easily :wink:
.

64

This is very cool
. something to think about

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I tried a bat stencil, sawn out of thin aluminium with a fret saw, but I made it too big, the edges of the wings do not receive enough light so they appear not sharp.

So it must be made tinier, not sure if that can be done nicely with a fret saw. And I’m not sure about batman either, maybe I will end up with something entirely different :partying_face:

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Cool! :beer: :+1:

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Jeff51 just posted about a batman projection contraption that uses a 100,000 lumen Imalent flashlight as a light source, and a 25cm fresnel lens with fairly long focal length. Pretty cool too, but not as silent, and maybe a bit less throwy than this one.

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The sky is the limit :sunglasses:

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Looks pretty good actually! :smiley:

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:laughing: :+1:

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Good effort djozz. :smiley: :beer:

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Tnx.
Today I got the 14AWG wire in so I could finish the battery carrier. I chopped the front section off the flashlight head 4mm above the shelf and sawed two grooves in the remaining rim to lead the ledwires to the side. Had to ream the holes in the shelf to 4mm diameter for these quite massive wires. Smoothed everything with sand paper so there were no sharp edges to cut into the wires. The wires were fixed in position with a good bit of kapton tape, does not look extremely profi but you are not going to look inside the lamp daily.
In the picture I show the old 18AWG wires too, so that you can see that 14AWG is a whole lot thicker.

I was lucky because with a 40T at 4.12V I measured 19.85 amps now, precisely what I was hoping for :slight_smile:

So now that the battery tube was shortened, I could check the maximum flood setting of the lamp, with the slider towards the lens with the battery tube touching it.

In the picture the flood looks a bit less wide than in reality because of the wide field of my phone camera. Trees are at 25 meters as always. (it looks like I borrowed Flahoholic’s van for the beamshot :slight_smile: )

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:slight_smile: Nice

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WoW

The beams are really awesome

Regards Xandre

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“The outside received a base-paint first, and then after some slight sanding, bright red!”

I missed the last update from a few days ago but “Wow, nice work, sir!” (Mooi rood is niet lelijk, toch?) :+1:

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mooi rood is niet lelijk herinner ik me uit de jaren 70 volgens mij, zegt iets over je leeftijd :slight_smile: :stuck_out_tongue:

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Nice beam djozz. Ever have trouble finding a car park?

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Not sure what you mean, but I do not have a driving licence, never needed one over here. (I can park a 20 meter steel barge though)

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I guess MRsDNF was referring to your “spotting light” to spot a place for a car! It guess it could apply to the barge too :smiley:

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Speaking of which, ships often have great spotlights, my cycle trip to work is along a small part of the Amsterdam port and I’m always jealous of those marine mirror lights. They cost a fortune though