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

Giveaways and Contests
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As built the back plate ended up being a little thicker than I wanted. I do not have a thickness planer so I elected to re-saw it from the inside surface, then re-sand that face. The thinner back makes for better interior clearances.

Here is the back with the heat sink assembly fitted…

A chisel was once again used to square up some corners, this time in the body where the back plate is mounted.

Now back to the front side. That gap under the window frame needs a filler piece. I cut some more wenge…

The perf board needed some support to provide its final setback from the padauk window frame. Some thin pieces of wenge were cut and glued inside the body.

On the left of the next shot, which is the top of the body, a narrow strip can be seen added to the interior. To the right in the image, near the lower end of the body are two strips, one on each side.

The perf board sits against the strips…

This seemed like a good time to finish off the body. In preparation for gluing the corners I cut off the exposed finger tips.

I used a small Japanese made, very fine toothed pull saw. The teeth have no set to them. The blade is 0.012” (0.3mm) thick and very flexible. Even though the teeth have no set I use a strip of masking tape as protection just because I want to. After cutting and gluing the fingers the corners were sanded smooth using the bench belt sander. I used CA glue and accelerator.

FYI, the teeth on one side of the saw blade are designed for cross-cutting softwoods, the other side with the smaller, more closely spaced teeth are for cross-cutting hardwoods.

At this point, there were a few glue line imperfections. These were filled with medium-thick CA and hit with the accelerator. Sanding with a 240-grit belt cleaned up the remnants of glue here and there.

…These pieces are ready for further work…

That does it for today. Thanks for checking in.

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A reverse clicky switch will be used. It could be mounted in the top to be in a convenient easy to use position. Or a side. I had planned to place it in the upper surface of the battery box I was originally thinking of using. I have decided to place the switch in the back plate, near the top. That way the light has a cleaner appearance from the front side and should still be easy to operate.

Two switches are pictured, both Omten 1288 types. Only 1 will be used but so far I am unsure of with bent tabs or not. Probably bent tabs…

I first drilled the 1/2” hole part way into the back from the inside. This is to fit the outer rim on the silicone switch boot. The inner hole was drilled with a 5/16” bit.

An additional block of wenge was used to make the switch body holder. That is a 15mm hole, drilled through the wenge.

That block will be glued as shown below. The switch with bent tabs will be pressed inside the 15mm hole. The ‘nub’ inside the silicone boot had to be shortened a bit to allow for proper switch operation, btw.

A groove was cut and chiseled out to provide passage for the switch wires. The lighter colored striped wood is bocote. That is a cover plate that will secure the switch in its mount.

Wires were soldered to the switch tabs. A small piece of redwood was cut to be a spacer block between the back of the switch and the bocote retainer strip.

Here’s a view of the rear of the body with the rear cover plate fitted.

That was one of the more complicated switch mounts I have devised for my scratch-made lights.

A back plate would usually be secured to the body with 2 or even 4 screws. I wanted to use as little visible hardware as possible. So the next step was to make a one screw system work.

After a bit of trial and error, I cut and sanded a small piece of hard maple. In conjunction with a small finger of wenge, this will make a catch for the upper end of the back plate.

With the maple strip and the finger of wenge both glued in place, the top end of the back plate is held in place as the back is inserted and slid upwards. There will be a single screw located near the lower end of the back.

Thanks for looking. That’s all for tonight.

34

That is a lot of work and thanks for sharing your detailed progress, Sir :beer:

35

It looks very nice and professional level.
Don’t forget to test the circuit during each step :slight_smile:

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With the upper locking assembly completed the next step is to make what is needed to use a screw to secure the back plate to the body. I use whatever scraps and cut-off pieces I have wherever I can. So here I used a larger block and a thinner strip to glue up a spacer block. Once again I used a couple of drops of medium-thick CA plus the accelerator.

With those glued together that assembly was glued to the body.

With that block assembly glued together another thin strip of wenge was sanded to just fit between those blocks and the back plate with minimal clearance. That strip was CA glued to the inside face of the back plate, positioned to be aligned with the block that was glued into the body. This is to reinforce the three glued up back pieces across the padauk glue joint. I intend to drill a hole through the back plate at the narrow band of padauk. It seemed wise to reinforce that.

Here’s the screw hole being drilled.

The hole was countersink for the flat head screw. It is a regular S/S wood screw. A pilot hole was drilled in the block n the body to make insertion of the screw easier and less likely to split the hard wenge.

The next step was to make a slot for the USB-C charger port. Two 3/32” holes were drilled and a chisel, a carving knife, and a small round file were used to enlarge the slot.

I’m holding the port in place in its mounted position for a trial fit. Looks okay to me.

I soldered the driver inside the copper mounting ring. That secures it and completes the circuit from the negative outer ring on the driver to the copper heat-sink unit.

The charger board is TP5000 based. It is a 1 amp version. I affixed the board to the heat-sink tab with a small bead of Arctic Silver epoxy. I have a half tube left and it still works well. I keep it refrigerated.

Then I tested the charger once again just to be certain it worked. I had also tested the driver after soldering it into the mounting ring.

Here are two images showing the assembled heat-sink with the driver, charger, USB port and wires attached.

The next photo shows the trial fit of the heat-sink assembly with the USB-C port connecting wires soldered. The bi-color charge indicator led will be fitted into a 3mm hole I drilled in the back plate. After the wood parts are all clear coated the electronics will be installed and the final wiring done at that time.

Next the wood parts need to be clear coated…

37

Very nice build, (as always :) ).
I would add some extra isolation between the positive tab and the cell since the tab is usually sharp and this shrink wrap is very thin.

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That is a good idea YuvalS. Thank you.

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After a light sanding with 320 grit paper the wood surfaces had a water based clear finish applied. The finish I used is made by Varathane. It is an exterior finish, chosen because it has UV inhibitors. These exotic woods usually darken after a while when exposed to UV light. They also usually darken when exposed to air; oxygen is the culprit. A good clear coat with UV inhibitors drastically slows or stops the darkening. This wenge is different. It can get lighter when exposed to oxygen and UV. This finish is only available in a brush on. Most clear coats do not have the UV inhibitors.

For the final coats I prefer a spray finish as that eliminates any chance of brush marks. I prefer lacquer as it dries fast and does not require sanding between applications.

The clear coat does deepen the colors of the woods a little. Five thin spray coats were applied. Lacquer dries for a re-coat in 30 minutes or less; more like 15 to 20 minutes with the generally low humidity where I am. It is best to let it sit for a day before handling very much.

Time to begin the final assembly. First up is the heat-sink unit. I cut some narrow strips of double sided heat resistant tape.

The heat-sink unit was pressed in place. In the past I have somehow managed to mix up the connections for the bi-color indicator led’s. That is a real pain to unsolder and re-do. This time since I have room to add a perf board pin header P did so in order to use plugin connections. The next image shows a three pin strip ready to be soldered to the charger board. The white wire had a terminal on each end; one to fit one of these pins and the other to connect to a leg of the bi-color led.

Here are the three connector wires hooked up. The led is about to be glued in place. It tests as being wired correctly. The USB-C port was also glued to the back plate.

Next the padauk window frame was fitted with a small piece of the Warlon Washi Shoji paper. It is a remnant from a previous project. It is made in Japan for use in Shoji screens. The paper is laminated with a thin plastic sheet for durability. It is affixed to the shoji frames with a thin double sided tape that has excellent grip.

The tape is 5mm wide. There are a couple of varieties for thinner and thicker papers. The instructions are quite detailed.

Here I have started the installation of the shoji material. After sticking the main strips to the window frame I trimmed the width with an X-Acto knife. The center strips of adhesive tape were trimmed before installation. The paper has been started by stripping off the protective layer of the single end piece of tape. Then the paper was aligned and pressed in place. It has been rolled back to expose the other tape pieces which still have the protective covering in place. If this was a larger frame I would also apply tape to the horizontal center rail.

…With the shoji paper held back the covering was removed from the tape…

The paper was firmly pressed into the tape and this is what it looks like from the front side…

On to the PCB board. It fits inside the box with very little slop. I cut two thin strips of scrap maple to act as retainers for the pcb. I used more of the double sided heat-sink tape to adhere the maple to the sides of the box. If I need to remove the pcb for some reason the maple strips can be pried off using a thin blade. I did not use the shoji tape as it is very difficult to pull loose.

On a suggestion by BLF member YuvalS I added some tape to the ends of the cell to help protect against the tabs cutting through the cell wrapper. I used kapton tape. I soldered needed wires to the tabs on the 18650 Samsung 35E cell…

Here everything is wired up and ready for the back plate to be installed…

The window frame is to be secured to the body of this light with two small pieces of the heat-sink double-stick tape. Test have shown me that this tape will come loose before the shoji tape in case I need to remove the window frame. However, it grabs enough to prevent falling apart on its own.

Several images of the completed and assembled light will be posted soon

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Here are five images of the completed light.

Front 3/4 view with 18650 cell for scale.

Lamp only

Lamp turned on with low brightness setting

Rear view

Rear view with USB cord plugged in. Red = charging.

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And finally, here is a video clip…

(It appears at the end of this video that Youtube automatically advances to one of the video clips of the logging feller/buncher machine.)

42

It’s amazing that so much work goes into something with such simple and elegant lines. Well done Don, as usual. Another beautiful light!

43

She’s pretty. Once again nice work.

44

Beautiful light. Great job.

45

Don, what a beautiful project. That turned out great! Following along, I must confess that it wasn’t until you papered the window that I finally understood what form the lantern would be. :slight_smile: It has such a classic heirloom look to it…the kind of thing like old desk and mantle clocks that could be found on top of furniture in every home. Wonderful job, really.

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Thanks for all the kind comments. I truly appreciate them.

This is going to be gifted at Christmas.

47

I love this. Want to build something similar for my wife to keep near the bed.

48

MtnDon, I have to say this: you are an inspiration! Not only because of this build, but because of the others you’ve been doing throughout these years!

I love the concept, I really liked the heat sink driver mount, and it is a classy and good looking build :wink:
Well done :+1:

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I want to take a moment to note that after operating on maximum output for an hour or so the body of this light does get warm to the touch. However, it never develops a hot spot and never gets more than warm to the touch. Not warm enough to get out the IR thermometer and take a reading. Same thing for the temperature at the heatsink while re-charging the cell. Warm, but that is all.

Thanks to everyone who had a look at what I did.

1 Thank
50

I appreciated the numerous fabrication related tips and tricks you shared with us in this build thread. :+1:

51

Aw shucks :blush: … thank you.