simple and reliable Rook Tail-cap Lockout mod.

After reading about ImA4Wheelr’s Rook 18500 Lithium Ion mod, i picked up my Rook to think of some mods to do with it.
The first mod was to convert it with a tail-cap Lock-out to eliminate that parasitic drain plaguing the Rook. I tried the tape cut-away method on the driver contact area, but the tape worn away very quickly after a number of twists from the head.

This tail cap mod works perfectly, and will work for indefinitely.

- First i removed the head, batteries, then the tail Cap, by using hot water and two strap-wrenches to break loose the loctite on the tail cap) Cleaned up the threads, then removed the three screws holding the negative-contact plate to the body tube.

- Next replace the three screws back into the body without the plate and tightened them in.

- Glue a round piece of high-density insulating foam rubber ( approximately 1/8” thick ) on the back of the contact plate to cover the solder spots for the springs.

- Place the contact plate back in the body, so it rests on “top” of the three screws, ( the contact plate will not twist with the cap as it has 3 little “divots” that align up with the 3 indents in the inside surface of the tube along the battery tubes, and always stay aligned when the cap is twisted to lock it out.)

- add some silicone grease to the threads, and the inside surface of the back of the cap to maker it easier to turn against the foam.

replace the tail cap on the tube with the contact plate back in place, ( resting on “top” of the 3 screws.)

put the light back together, and Voila !
A 1/4 turn or more of the tail cap releases the contact plate from contacting the screws on the plate’s board traces when the battery springs pushes it back keeping the foam against the tail cap’s inner surface) breaking the circuit, making the tail cap into a “Twistie Switch” to lock out the Rook eliminating the parasitic drain.

  • Image shows the screws back in the body, and the foam on the contact plate.)

My next mod to this light is possibly boring out the Body to D-Cell size, ( machining it to that dimensions will expose through the lands on the outside) then machining a body sleeve/tube/extender and inner battery sleeves and AA holders, so any cell from a D, C, 32650, 26650, 18650, 3AA, 3-14500, 4-AAA, 4-10440’s can be used, ( similar to a Lumintop SD10 multi-cell capacity.)

But first i have other projects on the plate, including the SRK super Thrower first. :slight_smile:

Very clever and simple solution that anyone can do. The best kind. Thank you for sharing. I like it better than my idea.

I guess Rooks have really fallen out of style. In its hay day, this mod would have caused much excitement. I'm going to do this mod to my wife's Rook (While I work out any kinks that my mod may have).

Hey DenBarrettSAR. If I wanted to bore out my Rook to fit a 26500 using my drill press, what type of bit would you recommend? I know I would have to be very careful since I would not be cutting through uniform, solid material.

Finished my mod on my light and then did your mod on my wife's light earlier this evening. Both worked great!

For insulator/spacer for your mod, I used a big mouth plastic bottle cap (like from a Gatorade or something) cut down to diameter of the battery tube. Used just the slightest touch of oil. Gives a super smooth glide in and out of lock out and allows the tail cap to be completely screwed down.

Dude, I think you have created the most benefit for amount of time and money required mod. Seriously, The mod takes hardly any time and no money. The benefits are huge:

  • No parasitic drain. This is major safety because the Rook will take 14500's to zero volts. Also just a big inconvenience.
  • Even in lockout, this mod keeps the 3 cells in contact with each other and, therefore, an in balance. Another huge safety benefit.

I like your mod better if using 14500's due to the above. I like mine better for single cell due to the lower resistance. I will need to adapt your idea to my mod for that safety benefit.

The only worry is the bit “grabbing” the three lands inside and damaging the tube or causing an injury, ( as standard twist drills have only two flutes.)
Being a machinist myself, i use a 4-flute end mill in a milling machine at higher tool speed of 3000rpm or higher for smooth Aluminum cutting, clamping the body using teflon V-blocks in the mill vise to keep it from moving and held solid.
the size required to fit a 26650 will be very close to the bodys’ outer surface at the base fo the outside lands, so it may risk in breaking-through the body. I haven’t taken measurements with a micrometer yet to determine if it can be safely done with leaving enough aluminum there so it dont break through.
Right now i really like your 18500 mod as the best cell upgrade to do as there is still lots of metal in the sides of the body to be safe there. :slight_smile:
Its nice that all of us here who enjoy “modding” lights, to make them better and more user-friendly. ( the manufacturers should be watching what we do with lights, so they can do it for us. :stuck_out_tongue:

Have a look at the quick drawing draft i did of the Rook body design below,
You can see in grey of the Rook’s outside lands cutaways in the body tube sides, and the inner original 3-AA tube bores.
The green ring being the 18500, and the blue ring being thr 26650, its the closeness to the outside lower lands that i have to measure befoe i bore out the rook body to fit a 26650.

On my 'To do' list. Thanks.

Oh wow. I didn't notice the potential issue with the outside lands. Thank you for pointing that out. Yeah, that mod is way outside my skill level and equipment. I would most certainly ruin the tube and probably hurt myself trying. I will settle for 18500's and 14500's and leave good enough alone.

Thank you again DenBarrettSAR. That drawing really helped me understand what you meant by landings.