6th Annual Scratch Made Light Contest - Flashy Mike's machined project

Flashy_Mike · 2018-11-27T23:40:34.000Z

Well, the circular 20x2 mm magnets are still missing. Yesterday I ordered other ones locally from Amazon, they should arrive tomorrow. These are smaller though, only 15x2 mm. Dependent on which batch arrives first (if any), I have to reprint the bottom plate.

Managed to finish the copper disc. Not too beautiful but functional. Was a pain, hands and arms do still hurt. Only minor injuries though …

I borrowed a step drill from a friend for the 28 mm center hole. For the small holes and the first steps of the center hole I used a small hand drill until it’s cells were empty. Didn’t want to wait for charging, so I took my fat and heavy hammer drill for the last steps. Both without drill mount and bench vise (which I don’t own). I screwed the copper disc on top of a wooden block before in order to be able to keep it in place with one hand.

There are still some smaller parts to print, I hope I’ll finish printing today.

DavidEF · 2018-11-27T23:13:04.000Z

Flashy Mike:

Managed to finished the copper disc. Not too beautiful but functional.

Must look worse in person. It looks fine to me, in the pic. In fact, I can’t find anything wrong with it. It looks like a manufactured part.

How much filament does it take for the bottom plate? If it isn’t too costly, you could go ahead and print the other plate, so that when your magnets arrive, you will be all ready to use whichever size you get in hand first.

Flashy_Mike · 2018-11-27T23:44:45.000Z

DavidEF:

Must look worse in person. It looks fine to me, in the pic. In fact, I can’t find anything wrong with it. It looks like a manufactured part.

Well, my sense of self is somewhat damaged after watching too many of CRX’s builds (which are pure perfection).

DavidEF:

How much filament does it take for the bottom plate? If it isn’t too costly, you could go ahead and print the other plate, so that when your magnets arrive, you will be all ready to use whichever size you get in hand first.

Its not a question of costs, less than 50 ct for the plate. But I don’t know how strong the magnets are. I would rather like to check first how many of them I need for the lantern before I do the redesign and printing.

CRX · 2018-11-28T00:07:19.000Z

Well, not quite but I am getting better
Copper plate looks good, hope them Neo’s arrive soon
N35’s? 15mm x 2mm should be fairly strong.

Flashy_Mike · 2018-11-28T23:32:03.000Z

Not much time left, getting somewhat nervous …

Finally got the locally ordered magnets. Designed and printed a new bottom plate and the disks which cover the magnets. Glued magnets and disks in.

And I assembled the upper part of the housing.

I married upper and lower part. The clear battery holder is - like the green components - made of ABS. All parts touching the hot copper disk are printed with ABS filament now which should withstand temperatures up to 100 °C. All other parts are PETG with a heat tolerance of up to 70 °C. The RGB status LED and the USB-Connector are glued in and sealed and should provide water protection.

I checked driver, bluetooth transmitter and charging board, everythings works well of so far. Tomorrow I will put the electronics in the housing, too tired now, its after midnight here. Hopefully the lantern will be completed tomorrow, I need the last day of the contest to make a video showing the remote function.

MtnDon · 2018-11-28T23:57:30.000Z

Way cool!!! Looking forward to seeing the finished product video

Makes me want to get a 3D printer.

MRsDNF · 2018-11-29T01:37:01.000Z

MtnDon:

Makes me want to get a 3D printer.

You dont need a printer Don.

Its amazing the parts that marry together to make your lantern FM. Looking good.

FmC · 2018-11-29T09:17:05.000Z

Keep going, almost there!!

pinkpanda3310 · 2018-11-29T09:32:46.000Z

Looking good seeing some parts fitted together

Flashy_Mike · 2018-11-29T17:54:39.000Z

I’m using a 5mm RGB LED (common anode) to display charging status (red and green) and bluetooth activation (blue). This is ok with the charging module since it pulls down the LED’s cathodes with open collector circuits. Unfortunately my bluetooth module is powered directly by an output port of the Attiny85, and I have to use this pin also to drive the blue LED since all other ports are in use. So I quickly soldered this open collector circuit with a NPN transistor I had lying around. Do you notice the little 603 resistor between base and emitter?

… and wrapped:

The driver PCB in place with a printed spacer. The space under the PCB is filled with heat conducting cubes to ensure a good thermal connection between driver and copper disk, both for cooling the 7135 and thermal regulation.

The bluetooth board sandwiched on top of the driver with another spacer on top.

Inserted cells and the charging PCB which sits firmly in grooves. Soldered a lot of wires …

Before screwing in the botton plate this blue printed part is plugged in, it fixes the cells in axial direction and presses the boards sandwich firmly to the copper plate.

And - finally - my camping lantern is finished!