Jensen567's Entry for the 5th Annual Old Lumens Scratch Build Contest - Machine Made Category

Thanks! Taking my first cuts. I’m just going to start with the 21700 tube light because I’m almost positive I can get that done in time, if it goes quicker than expected I’ll try the scaled up M1 as well.

EDIT: Sorry if I format this all wrong, but I am going to start putting all the pictures in the reserved posts only after this one.

Looking forward to the build Jensen. :beer:

Good luck with your build - looks like you have got out to an early start!

Really all I have done so far turn the outer diameter of the battery tube to see how it looks, I like it so far. Unfortunately the x-axis on the lathe DRO has gone whacky, so I’m back to using the knobs and measuring manually.

I’m also drawing some parts in solidworks and looking around Kaidomain for lenses, reflectors and switches. I’m considering a few different optics too.

Anyone know where I can buy a Samsung INR21700-30T? I realized I don’t even have a 21700 battery to check the tube sizing.

Maybe you can HKJ about where to get the battery! :wink: He did a review of those: Test/review of Samsung INR21700-30T 3000mAh (Gray) .
Good luck with the build!

Been awhile since I updated this. Ordered some tools from China almost 2 months ago, and they finally came in last week. So had a chance to do a bit more work.

As of now, plans have changed, I decided a tube light on this scale just wouldn’t look right with the Khatod quad optics I want to use, so instead it will have a slightly larger head and tailcap than battery tube.

Speaking of battery tube, I finally figured out how to thread on my lathe, so the tube is done! Final dimensions are 25.4mm OD, 21.5mm ID, 75mm long. Threads are a weird mix of metric and inch since I couldn’t get the metric pitches to work right. Its a 25mm major diameter, 22.9mm minor diameter, and 18 threads/inch.

Next I will probably try to get the tailcap machined, and will see how internal threading goes. Now, on to the pics

One side threads about done, first time cutting threads on this lathe.

Shaved to length and threaded the other side, as you can see a 21700 fits nicely.

Sandblasted to clean it off, and because I just like the finish that way.

Its good to see an update Jensen. The threads look real neat. I’m liking the sand blasted look but maybe would of not done the threads.

Good to see more progress :+1:

Any progress is good progress, unless small assistants are involved, then it may not actually be progress.

I thought about that, but I plan to do a bit of hand finishing with a triangle file, then use some nice Teflon grease so it should be OK.

Had a little bit of time today so I made the copper insert for the light engine and started the head. Cut my first internal threads on any lathe ever, and they actually work!

Right now the plan is to have the head be mostly aluminum, then have a press fit copper insert that holds the MCPCB and driver so I can solder the driver in rather than having to make a retaining ring setup. Not sure my tooling could even do threads fine enough for that. On to the pics!

Boring out the driver pocket

Emitter side

Driver pocket

My first ever internal threads. It fits!

Nice work on the threads Jensen. :+1:

Looks good :+1:

Quick update for this morning’s progress. Machined out the front of the head and pressed in the copper insert. It has a 0.01mm ish interference fit, and if I had thought ahead some I would have frozen the copper and heated the aluminum, because holy cap was it tough to get in there. I actually bent the handle on my vice beating it with a hammer. But it’s in, and it won’t be going anywhere. If I were to do it again I would just press a copper slug into the aluminum tube, then do the driver and emitter pockets, and the head threads after, was nervous about messing up my previous work, but it worked out.

Once it was in I made a quick pass with the boring bar to clean up the scuffs and open the hole up enough so the optics can drop in. For the first time I think I can actually see this maybe becoming a flashlight.

Copper insert pressed in, look at those score marks! Thing won’t be moving anywhere, plus thermal and electrical contact won’t be an issue.

Cleaned up and optics dropped in, now I just need to cut the head down to length and figure out the bezel. And of course give it some style. Starting to be able to picture it as a light though!

Lots more progress today. Head is done! Just need to fill it with the electronics. The bezel ended up being deeper than I wanted, which means the optics sit pretty far back from the face (about 3.5mm), but on the plus side it should be more resistant to something breaking the lens.

I’m getting really excited now, it actually looks like a flashlight, and seems like everything should fit well. All I have left is to build the tailcap and switch.

Bezel made and the top of the head threaded. Fitment of everything is good, should hold the MCPCB to the head nicely for thermal transfer. I lost a bunch of pictures between these and the next one.

Completed head! I shaved the outside down to 27mm, and shortened up the bezel as much as I could, then added the grooves. Grooves are mostly just for looks, not deep enough to make a huge impact on heat transfer. Finally I sandblasted it all aside from the bezel threads, and screwed the tube on. Really excited to see this thing light up.

I also did start the tailcap by making the brass insert ring I will solder the driver to. I figured I would employ a classic Old-Lumens method, and make something out of plumbing hardware, so an extra fitting from my bathtub install was used as the material.

Switch is a nice beefy Omten PBS-101 on a 20.5mm board. Bonus of having the larger diameter cell is you can easily use the larger Omten switches. I was originally going to go with a 22mm PCB, but I found this assembly so went with it.

Coming along, looking good!

What Don said. Looks like you are going to finish in plenty of time. :+1:

Yep, coming along fast! You’ll be sitting down having a drink by the time I get mine done. :partying_face:

Well I sort of made the decision to just say forget all the plans and drawings, I’m just gonna build the thing and solve the problems as they come. As a result I’ve spent a lot more time actually making the light and less trying to figure out how I can make it perfect. Along the way I’ve learned a lot, and could probably make a second one much nicer.

I’m hoping to have it done by the end of this week or early next week, then I’m going to enjoy the heck out of it because it’ll have lots of run time and beautiful tint. Plus I may have the only light designed specifically for a 21700 right now.

looking good