Slim 2, my first scratch light

gadget_lover

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Well, I finally finished my first scratch light. My previous attempt was a piece by piece replacement of a Dorcy that I named "slim". This one was made from my own design. I've named it Slim 2.

My objective was a short, thin, light weight EDC with a clickie that could be set on end. It had to run at least an hour and be as bright as my ARC LSH-P. It had to be modular so that as I screwed up each piece I could make a new one.

The light was created from 2011-T3 aluminum. The primary tool used to create it was a Harbor Freight 7x10 lathe. I also did some very minor machining with files and a harbor Freight micro-mill and, of course, I used a soldering iron.

The light is made of 5 machined parts, bezel, head, heat sink, body and tail cap. The electronics were taken from a Dorcy 1AA 3 LED light. The switch and LED were taken from a Costco 2AA luxeon. The LED is a QWOK. The optic is changeble by simply unscrewing the bezel. Right now it's an NX05.

The light draws 475ma on a fresh battery, for a computed 2+ hours on a single CR123A. It weighs in at .8 oz (22g) without battery.

I need to learn how to temper it to T8, which is a nice hard temper.


Here's the light, sitting in front of an ARC LSH. Notice the flush pushbutton.
slim2_1b.jpg



Here's Slim2 next to the ARC LSH with twisty tailcap.
slim2_2a.jpg



And here's Slim2 with his predecessor, Slim. Slim is on the left.
slim2_3a.jpg



This picture shows that I made my objective. It's almost as thin as the ARC AA on the right and is shorter than the ARC LSH with TSP on the left.
slim2_4a.jpg



And last, some other lights for perspective. Left to right; Dorcy 1AA modded to the max, Stock Dorcy 1AA, Slim, ARC LSH-P w/TSP, SLim2, ARC AA, ARC LSH w/twisty.
slim2_5b.jpg



This is a one of a kind light. I will not be building more for sale. I just wanted to show others what can be done with fairly cheap tools and fairly poor skills.

Daniel
 
Wow nice work! I recently caught the single cell light bug and looking at the slim series especially slim 2 makes me drool. Too bad it couldnt have been my first custom light.
 
Good looking light, Dan!

I think you will find machining full-hard aluminum alloys easier than the softer ones.

Larry
 
Thanks for teh nice words, guys!

Pablo, Yes, I've been clicking it all evening. It's a different feel than any of my others. I have to say, I'm more impressed by your NEOCA. That's a very pretty piece of work.

Mags, Yes, the little ones are more of a challenge (in my opinion) AND you can fit more of them on your collection shelf. /ubbthreads/images/graemlins/smile.gif If I ever get a CNC lathe going I'll see about making a run of these.

Larry, I did find 2011 easy to work with. Less digging in, faster cuts and it didn't ding when I dropped it (5 times!) while making it. Now if I only had a set of collets to make it easier to swap the components....

Thanks again.


Daniel
 
/ubbthreads/images/graemlins/thumbsup.gif /ubbthreads/images/graemlins/happy14.gif /ubbthreads/images/graemlins/clap.gif /ubbthreads/images/graemlins/goodjob.gif
 
Outstanding, Daniel. I'm looking forward to seeing at the next get together. /ubbthreads/images/graemlins/oops.gif you canceled out on that one. How about the next Bay Area get together.
 
Dan, I sure hope you can make it to SHOT. (Jim, on the other hand... /ubbthreads/images/graemlins/grin.gif ) Sorry for the OT- it is a nice effort. I'm not familiar with that alloy, and curious how it will anodize.

Larry
 
[ QUOTE ]
tvodrd said:
Jim, on the other hand...
Larry

[/ QUOTE ]

Sorry to dissapoint, Larry, but I'll be there /ubbthreads/images/graemlins/nana.gif

I am, however, having trouble locating my pink hat, but I'm sure Darell won't be hard to miss
bellyemoticon.gif
. That's who you should be worried about /ubbthreads/images/graemlins/crackup.gif
 
I like the 'out-takes' scenes when I watch a movie, so I figured I'd give a quick behind the scenes look at the making of a light.

First of all, the lathe was not the most used tool. The digital caliper was. It was used over and over to measure parts, clearances, depths, etc. It was used before the design, during the machining and at virtually every step. The second most used tool was pencil and paper. By planning each step you avoid little things like boring a 3/4 inch hole in a body that has a spot that's only 5/8 inch thick.

The picture below shows the paperwork that was my design. A hobby grade lathe like mine can actually get to within 1/1000 inch of what I designed. I was able to make duplicates when I messed up a part because I had the dimensions written down.

slim2_8.jpg



The original design called for inside threads for the tailcap like a Mag and a Kroll switch. I gave that up because it would have required a threaded insert for the kroll. The battery is bigger (.655 in diameter) than the kroll (.625) and that mandated that the bore of the body would be just slightly bigger than than the threads of the kroll. I discovered the switch in the Costco AA was mounted on a circular board that was .655 and shorter than the Kroll. That led me to make the tail cap so that the body has outside threads and the tailcap has a skirt that will cover an o-ring. This also allowed me to cut a groove for an o-ring without cutting through the threads.

In the center of the picture you see some parts. Those are 'leftovers', also known as screw-ups. Here's a close up below. The pretty ring on the left was supposed to remain attached to the body. I added an o-ring that was not on my plans, making a spot that was around .625 inches thick .3 inches from the end. I then bored out the end for the electronics. Yup. .625 inches and .330 deep. That very effectively cuts off the ring.

The 'leftover' body is much longer than needed to provide 1) a surface to grab with the lathe and 2) left over material to make a couple tailcaps the same diameter as the body.

The flat disks are leftover threaded material for heat sinks. It was cut off the threaded end just before I bored it.
slim2_7.jpg


Below is the whole light disassembled. Notice that I made 3 mistakes with the LED/heatsink. 1) The LED is centered, but the phosphor is not, so the hotspot is slightly off center. 2) The red wire going from the electronics to the LED had a break somewhere. I had epoxy'ed it on, so instead of tearing it apart I drilled an extra hole and added a second wire. 3) I forgot that you can't solder to aluminum, so I had to add a screw at the last moment to connect the LED to ground. I grabbed a spare screw and threw it in there to keep the ground tacked down. It's too long but I'll trim that down later.
slim2_9.jpg


Daniel
 
Hey Dan, you should see my "screw-up" collection. /ubbthreads/images/graemlins/icon15.gif (Save them, they might prove useful in the future!)

Larry
 
Wow!!! Impressive "behind the scenes" footage... I wish more light makers did this, it really adds the feeling of almost being there... I notice you didn't state the total number of hours involved... I'm betting around 100. /ubbthreads/images/graemlins/smile.gif

Looking forward to seeing it in person at the next get together...

-J
 
Thanks John.

One of the neat things about metal working is that you lose track of time. I built Slim 2 over the course of three weeks, with a 2,500 mile road trip thrown in the middle just to confuse things. It actually sat in the jaws of my lathe for almost a week while I drove to P-hoe-nix Arizona and San Diego. Note to self: Next time check the alignment of anything that sits overnight.

I did the design while watching TV with my wife, measuring things during commercials. Then I let the design sit a day while I review it mentally in idle moments. I don't count this time. /ubbthreads/images/graemlins/smile.gif

The actual metal working was much faster the second time. By then I was sure of what I was doing and able to make bolder cuts. Of course, by then I also had the lathe's gears set up for the right threads, I'd calculated the necessesary thread depths, etc. It was probably less than 30 hours of actual work time.

Once you have all the calculations written down and once you are sure that you are not going to bore though a wall, it's much easier to work. Cutting through a thin spot is a real problem, so the first time you follow a design you find your self being super cautious and deliberately taking extra small cuts.

I bet I could build the next one in 20 hours or less. Maybe I'll time it.

Daniel
 
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