MtnDon's 10th Annual Old Lumens Challenge Entry - Hand Made Category

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MtnDon
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MtnDon's 10th Annual Old Lumens Challenge Entry - Hand Made Category

Here we go, off to a quiet start.

More to come as things take shape or at least I try to make an idea take shape.

MtnDon
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Some days one must simply give into a crazy notion and go ahead just for the fun of it….

It’s a triangular scrap of glued-up wood, a cut-off from some old project, a 2032 cell and a 5mm led from rngwn in 1900K and 95+ CRI. A couple of minutes with a Dremel tool cutting a slot for the cell and a little sanding and we have a hand-made light.

Perhaps one of those parts may make it into my completed entry?

Scallywag
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MtnDon wrote:
Some days one must simply give into a crazy notion and go ahead just for the fun of it….

It’s a triangular scrap of glued-up wood, a cut-off from some old project, a 2032 cell and a 5mm led from rngwn in 1900K and 95+ CRI. A couple of minutes with a Dremel tool cutting a slot for the cell and a little sanding and we have a hand-made light.

Perhaps one of those parts may make it into my completed entry?


I love a good chuckle. It makes light – who knows if my entry will ever get that far this year!
MtnDon
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Images are clickable to enlarge them….

My idea is more along the lines of a lantern than a conventional flashlight. But even then my idea differs from what would be expected for a typical lantern. Lanterns generally spill light in a circular pattern, all around the globe. The plan here is to have the light aimed in one direction, but not so focused as would be with reflectors or optics.

I have built or modded lights with single emitters, quite a few triples and some quads, a couple of six emitter lights and one twelve emitter light. As far as the number of led’s this will beat all previous efforts in the number of emitters, if not the number of lumens output or distance of throw. Forty emitters will be used.

The emitters are 5mm leds purchased form rngwn. They are 1900 K high CRI. They are nominally rated at 2.7 volts and 20 mA. Rangwan has a page where these may be bought. djozz tested some of this type in 3400 K and there is a report with graphs re lumens, amps, CRI and so on.

Here’s the bag they came in…

The leds will be mounted on a piece of single sided prototype perf board, 6.5 cm x 14.5 cm (2.5 inch x 5.75 inch). The copper traces are laid out to be continuous down the length but they do not connect to each other.

After a bit of diddling about with my mental concept I came up with a 5 × 8 grid of leds. The size grew out of making something of a physical size that I liked and was compatible with some of the materials I have already, as well as compromises between driver maximum amps and how that would work with the leds. The tests djozz performed indicates these leds can take much more current than 20 m, but like most or all leds there is a point when more heat is made than light. I hope I have reached a happy medium. I anticipate that mostly the light will be run on a low setting, likely no more than 20 mA per led.

Here is a representation of the 5 × 8 grid. The leds will all be wired in parallel, so there will be some jumpers at the ends of the rows.

And the other side of the perf board with led positions marked.

A close up of the perf holes which are approx 1mm in diameter on the standard 2.54mm spacing. The long leg is +.

The first row of leds are positioned to get a “feel” of what this may be.

Here’s the row with the wires bent to hold the leds in place.

Next, I need to get out to the workshop and turn on the soldering station and make a commitment.

Yes, I am excited! But we’re going away so there will be no updates for a week or more.

Scallywag
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I’m excited, too! Interested in what you come up with for the housing.

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Looking good so far Don. See you in a week!

MtnDon
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I laid out rows of the 5mm LED’s 8 at a time. After applying liquid flux with a flux pen each wire leg of the LED was soldered to it’s copper trace. Before soldering I checked each row by jumping a 2032 cell to the pair of traces to check the polarity.
Then on to the next row of 8. After the LED’s were all soldered in place, short copper wires were used to form jumpers between all the positive lines and all the negative lines.

A further check with a 2032 cell has them all light up.

Now to build something around that.

1Peter1
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Very cool! Cool

Rdubya18
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Looking good Don !

MtnDon
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Today I did some wood stuff.

This is Wenge, (WHEN-ghay). It is quite hard and can be splintery. I’ve never used it before, in part because of its splintery nature and that it is expensive. I got a piece of it at a sale price a while back. So far I haven’t had any splinter issues, but then I have been watchful. I re-sawed this from some thicker stock. These pieces are just over 1/4” thick. That is a Samsung 35E 18650 cell for size comparison. This cell was purchased some time ago for a project that did not happen and has solder tabs spot welded to the terminal ends. I have two and may decide to use them both in a parallel configuration.

Wenge, like a few other exotic kinds of wood, blunts tool edges quicker than some woods. I decided it might be a good idea to cut the notches with a new 1/4” solid carbide bit in my router, rather than an older and much-used bit.

Those are called finger joints or box joints.

These will be glued together to make a box, which will hold a 18650 cell plus some other components. This is still a concept that will likely undergo some changes.

At present, the sides are 1-1/2” high. They will probably be cut down, but I am not certain how much yet. The corners will be glued with hide glue and once the glue has dried the fingertips will be sanded off. That is something I strive to NOT do to my own fingertips. That hurts.

I’ll see how this works and what it looks like with other parts I need to make to bring this to fruition.

Scallywag
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Hey Don you must have a little practice with joinery! I could ruin a lot of wood trying to get that right.

MtnDon
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I have had a little practice. Wink

grin
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Nice timber the grain makes the surface look like is has ridges.