The A-AA2, my second version of the battery vampire - picture heavy

Most of the raw materials needed to make this light

From the upper left to bottom, left to right - wquiles Joule Thief driver, XP-E, 17mm reflector, V10 glow powder, assorted O-rings, 5/8" brass rod, 3/4" clear acrylic rod, 7/8" clear acrylic rod, 3/4" 7075 T6 aluminum rod, 1" 6061 T6 aluminum rod


I decided to start with the tailcap since this is easier to make than the head and the body should be done last.
First, chuck the 3/4" 7075 in the lathe


Face the end


Lightly turn down the outside



Turn down the threaded portion


Cut it down to the target diameter of 16mm


Using the threading cutter, debur the sharp edges



Cut a groove where the threads are going to end



At this point I didn't like the amount of threads that I was going to end up with so I decided to cut the shoulder back and give it more threads



Cut a new groove for where the threads are going to end



Using the parting tool, cut a groove for the O-ring



O-ring installed


Cut threads



The setup for drilling out the tailcap


Starting the drilling with a centering drill bit


Moving onto a 1/8" drill bit then a 1/4" bit and eventually the 3/8" bit



Chucked a 3/8" end mill in the drill chuck and squared off the corners inside the hole


The next three operations uses three M10X1 taps, the first being a standard tap, the second being a modified one that is almost bottoming, followed by a bottoming tap. Only about three threads are cut





Using the parting tool, start parting, but,stop after a few millimeters so that I can bevel the edge then part it



Reinstall the turning cutter and rotate it 15 degrees to put the cutting edge at a 45 degree angle


Cut a 45 degree bevel then finish parting the tailcap



Remove the 3/4" aluminum and chuck the 5/8" brass then center it


After a quick facing operation turn it down to 10mm then cut half of it to 3/8", about 9.4mm



The tailcap slides onto the narrower part, but, not the wider part


Cut a groove to differentiate the two parts I'm making


Using the center drill again, start a hole, followed by a 1/8" drill then a 7/32" drill



Using a 1/4"X20TPI tap, tap the hole



Part off the internally threaded retaining ring



Using the centering drill, clean up the edge so that the drill bit goes in centered



Using the threading cutter, bevel the hard shoulder for clearance before threading



The tailcap threads onto it


Part it off


Reposition the brass about 7/8" further out, face it then turn it down



The left-most part is cut to 14.5mm. The right part will be cut down to 1/4"


The externally threaded retaining ring slides right on


Mark where I want the threads to end and thread it to 1/4"X20TPI


The internally threaded retaining ring screws on


Taking advantage of the handy retaining ring holder, I cleaned up the excess brass left from parting


The relationship of the three brass parts and how the tailcap attaches



Bevel the sharp edge


Next, cut a groove for the O-ring using the parting tool and install it



Using the turning cutter, cut a bevel


Part it off



The plunger assembly assembled. The internally threaded retaining ring is locked down using Loktite


Reposition the mill head assemby at 60 degrees, install the tailcap in the four jaw chuck, then center it on the Y axis



One notch every 60 degrees


Reposition the mill head assembly at 30 degrees, rotate the tailcap 30 degrees and cut another series of notches 60 degrees apart




Remove the chuck from the mill and attach it on the lathe


Face the tailcap. Shiny finish


Cut grooves into the face of the tailcap



Ready to assemble, but, the spring is too long



Tailcap assembled showing the fully extended length and the compressed length



After the last picture was taken I adjusted the spring length and that allowed the plunger assembly to have a longer travel, about 1/8" total.

Tomorrow, the head...

Wow. That is so cool. I
Wish I could mill and build stuff like that. It's s lot more complicated than I ever imagined.

That notched piece is beautiful.
Oh the possibilities!

I think I'd have custom tailcap, battery tube for all my lights but let the companies do the R&D for the business end.
Very skilled.

Now this is the kind of build log I'm always wishing CPF had more of. Great documentation PCC, this one goes into my subscribed threads.

After giving it some thought I had realized that I had made a mistake: the diameter of the aluminum tailcap is too close to the diameter of the O-ring and the O-ring will contact the threads of the body. To test this I took a scrap of acrylic rod and made a piece that will mimic the body.

The scrap acrylic


Chucked in the lathe and faced






Drilled it, first with the center drill then with a 1/2" bit






Using the small boring bar, opened it up to 15mm


Cut threads until the head fit (removed the plunger assembly for fitting)




Cut off the end of the threads for the O-ring and flare the end to allow the O-ring to slide in






Just as I had suspected, the plunger is too large and the O-ring groove is not deep enough. You can see that I'm putting pressure onto the tailcap trying to force it into the body and it's not going.


The plunger itself needs to be redone so it's not a total loss. The remaining pieces can be reused. Since the steps to make the replacement plunger are essentially the same, just using different dimensions, I won't document it here. Needless to say, I'll be using a smaller O-ring in addition to the plunger with a smaller diameter. Flying by the seat of the pants has its ups and downs...

Wow, amazing to see how many steps it takes just for a single tailcap.

Tailcap side indentations look awesome BTW. Great job!

I just love the flashlight name: "THE BATTERY VAMPIRE!"

The honesty in the name floors me. And, it rings strikingly similar to my friend's now defunct Home Building venture, named, "The Wallet Vampire Builders" LLC.

Looking forward to more of your Vampire Diaries.

Nice build log! Eagerly awaiting your next update :thumbsup:

Finished the plunger. It now works the way I had wanted it to.

Picture shows the finished tailcap, the slug of 1 1/8" 7075 T6 scrap that I found, and the temporary piece to test the threading of the head and tail. Mind you, this scrap piece was what was in the chuck while making something else and that other part was finished, leaving this piece of aluminum.


The aluminum is installed in the centering four-jaw chuck that was installed in the lathe. The saw marks on the back of the slug needs to be cleaned up.




It didn't need to be completely cleaned up just yet. The small contact area where the chuck holds the piece had me worried that the piece would pop out of the chuck so I cleaned it up with skimming cuts and it took quite a few passes to get to this stage and I wanted to cut the other side to get more contact area


Reversed the piece and started removing material. I centered it around the smaller diameter part






Using the threading cutter, removing the sharp edges


Now that there's a longer shoulder for the chuck to grab onto I flipped the part again and turned down the outside to match the diameters then turned it down further to 22.7mm. The target diameter is going to be 22.2mm, which coincides with 7/8"




Now that the diameter is closer to where I want it to be, I can finally finish facing it




Rotate the facing tool 45 degrees and cut a bevel


This is as far as I was able to get to today. Tomorrow I should be able to start the pocket for the reflector and emitter. The other end still needs to have the diameter reduced to 16mm, the 0-ring groove cut, threads cut, and the pocket for the driver. After that the positive contact and some other things made to get the head finished.

Really nice work there PCC, and you made it look easy :thumbsup:

Maybe it's time to finish this one...