Solarforce L2M flashlight with neutral XP-L Hi drop-in

Sturdy and affordable Solarforce L2 family of flashlights had a numerous worldwide following not so long ago, mainly within hunting/outdoors and flashlight enthusiast communities. L2's "tactical" appeal, moderate pricing, Lego-able design with a set of accessories, P60 drop-in compatibility and general parts interchangeability with a line of flashlights made by a major U.S. manufacturer were additional reasons for owning one. Or  more than one...

Today these flashlights are still being sold online but genuine ones are getting somewhat harder to locate. Company web store has lots of L2-related items on sale with hardly any new products in sight (AFAIK last update to this series went on in 2012). It seems like this brand has seen better days so I couldn't miss the opportunity to order their L2M (Mini) flashlight host which was listed as "deal of the week" offer at the time. To complete a Lego set I also ordered one "1000 lumen" Cree XP-L 3-mode drop-in and pair of Soshine brand 18350 Li-ion batteries from AliExpress, plus one multicoat anti-reflex lens from KaiDomain.

Flashlight body arrived within 20 days from the official Solarforce web store, drop-in and AR lens travelled a bit longer while batteries took a 70-day trip around the world since Li-ions are no longer shipped onboard commercial aircraft so they obviously had to take the slow boat from China...

L2M host (i.e. body kit without drop-in) includes: L2 head with low-profile bezel ring (plain glass lens & O-rings included), M-type short body, 18650 extender tube and a forward clicky switch. As usual,  my "Mini" sported some fine machining and very good HAIII anodization. Aftermarket drop-in has a nicely centered emitter and impeccable orange peel reflector. Both batteries are charging fine on my Nitecore D2 charger. All set for some Legoing!

Normal procedure on all P60 flashlights is to fill the gap between drop-in and flashlight head with a suitable thermally conductive material. I used two copper foil inserts to form a tight fit here and enhance heat transfer from emitter to flashlight body. Maybe that sounds a bit overkill but my old first-generation Solarforce LC-XML single mode drop-in normally created stupenduous amounts of heat, so it got tightly wrapped with paint-stripped beverage can aluminum foil from day one. It's not copper but still does a very good job.

Driver PCB was not properly seated in the drop-in body - it needed a bit of adjustment and additional soldering. So out came my old Soviet-made 40W soldering iron. No big deal, I even rated the item 5/5 on AliExpress.

New lens also received a bit of extra care - I've cleaned it using pure ethanol and a paper towel. Makeshift tool (carefully fitted 3.5mm thick PVC tab) and a pair of pliers helped remove the bezel ring, which sat in its place like it was glued. Small amount of silicone grease helped O-rings and threads operate as they should. As a final touch, surfaces of reflector and lens were dusted off with few blasts of air from a balloon pump.

This is the final product. Note the blue reflection of an AR aftermarket lens:

"Mini" in its stock version is already noticeably shorter than "classic" L2 powered by 18650 battery, but you can make it even more compact if you install the L2-S7 "tactical" switch. Unfortunately this ultra-short version is rather difficult to handle due to small grip surface. Switch shown here is a stock forward clicky. Old L2 models didn't have serial numbers:

"New style" switch boot with a brand name on it (AFAIK it's a 2012 revision). Old style rubber boot had smaller diameter and checkered surface, but this also differed across various L2 switch types:

Exact size reference - a bit less than 105mm (rubber boot included). As previously said, L2 Mini can get even shorter:

Solarforce L2M short version (powered by one Soshine 18350 battery) is my current EDC flashlight and real-life testing proved that it was well worth the effort...


Flashlight specs:

Brand/Model: Solarforce L2M

Description: CR123A/18650 P60 flashlight host, short body with extender tube, tailcap switch

Battery: CR123A (1 or 2); 16340/18350 (1 or 2); 18650 (1)

Body/head material: T6063-T6 aluminum alloy, black HAIII anodized

Emitter: LED, Cree XP-L Hi V3 (factory dedomed), 4300K (neutral white), approx. 700lm OTF

Driver: voltage 3.7-4.2V, 3-mode (Hi>Med>Low), last used mode memory feature, PWM regulated (sourced from AliExpress.com)

Reflector: light orange peel (LOP)

Lens: mineral glass, multicoat double anti-reflex (AR), 28x2mm (sourced from KaiDomain.com)

Switch: tailcap, forward clicky, 3 Amps max.

Waterproof: yes, IP rating n/a

Farewell to an old friend

This old machine has been driven away to its new owner yesterday. Our trusty 27yo Volkswagen Golf II 1.6TD was like a family member to us. I hope its new owner will treat him as good as we did. Goodbye, old friend...

Casio MW-240-1BV On 18mm NATO Strap

Casio MW-240 (module 1330) is a slightly oversized, minimalistic, high contrast easy reader quartz which looks nice and can be ordered online for a mere 16 Euros. Its dedicated resin bracelet fits the 16mm lug width.

This mod is about widening the space between lugs to accomodate any common 18mm bracelet, NATO, Zulu or other one-piece nylon strap. Note: This Casio is brand new so its 2-year full warranty is now void.

Lugs are manually filed down using two grades of round and rectangle needle files. Originally I've planned to use Dremel tool but decided not to since there was a huge probability of messing up the case if the attachment slips. Lugs are inevitably thinned (=weakened) in the process, so their inward surfaces were intentionally filleted and fillets carefully rounded with 600 grit carbide paper to reduce stress concentration and - hopefully - prevent them from breaking (see image below).

Since original lug holes were removed with the excess material, new ones had to be fabricated using the state-of-the-art propane burner & paperclip technique. 17mm spring bars are used here to reduce outward pressure on the lugs, and so far they are holding OK.

Next time I'm going to sand a milimeter or two off the crown guard (shoulder) since crown is too recessed by design and it's quite difficult to pull it out with an average fingernail. This of course requires removing the case back and stem...

New OD Zulu strap with black hardware:

Poljot Alarm Watch

Back in the early Eighties this "Poljot Alarm" was my first "serious" watch. Although the signal buzzer feature was mercilessly abused, watch served me for years as a school-time alarm clock and medication reminder. Later came the plastic fantastic diver Casios...

As far as I know my Poljot features 1. MChZ cal. 2612 mechanical movement with manual winding and 18 jewels,  alloy case and screw back. This is an export version with all-Latin lettering, probably bought new from Polish traders who at the time offered various Communist Bloc goods on flea markets.

When you entrust an elementary school kid with a complex and sensitive mechanical instrument you can't expect it to last long, but this watch is still operational in spite of obvious water damage, some drivetrain hiccups and general neglect over fhe few decades. I currently have no plans for its restoration but my kid loves the buzzing signal just like I did some 35-ish years ago...

Casio Edifice EF-503 Quartz Chronograph

Searching for my brother's Casio LIN-164 that needed a battery change I've found another interesting item: my old and supposedly broken Casio Edifice EF-503 was scraping against some nasty Chinese knock-offs on the bottom of a grocery bag destined for a garbage bin. It was me who discarded this Casio some six years ago, profoundly disappointed in this brand because my beloved watch completely stopped working a couple of days after its first battery change - no-brainer work performed by a well known downtown Belgrade watchmaker. I returned my dead Casio back to the shop hoping it was just a a hiccup, some trivial electrical contact issue or other thing of a sort, but watchmaker kept the watch for seven days and still couldn't find the reason why sturdy and reliable Citizen-Miyota OS10 movement failed miserably after some 2 1/2 years of normal use... Casio's 2-year warranty had expired by then and price estimate for a movement swap was very close to price of  a new watch, so I decided to take my ill-fated EF-503 home and dispose of it. Yet I didn't throw it in a garbage bin as I meant to do in my thorough disgust. Soon I bought a 2010 Seiko SNK803 "Desert pilot" automatic as a replacement,  had some important changes in my life and consequently lost track of a crappy broken Casio, nevertheless a bitter taste in the mouth remained.

Having recently read this tutorial on DIY repair of quartz watches, I was hoping that something still could be done with my Casio, so I've removed the screw back using an old Richter compass instrument, taken out the expired battery, carefully scrubbed off the gunk around the gasket with a wooden peg (highly praised certified watchmaker didn't bother to do any cleaning prior to battery change), removed the stem/crown (has to be fully in before you can unlatch it, pressing a recessed tab), pryed out the white plastic retention ring (four prying points are clearly marked on the mov't back plate) and gently taken the movement out, blew some compressed air around and inside and then installed it again, inserted the stem until it clicked into normal (running) position, applied silicone grease on a clean gasket and finally finger-tightened the lid, as I planned to get a proper new battery tomorrow morning...

I also had luck with my bro's blue dial Casio LIN-164 that day: battery change and gasket cleanup/lubrication went OK, without any scuffs to its beautiful matt gray surface... This watch has an ultralight blast-finished Titanium alloy body and bracelet which is held in place by two split pins instead of spring bars. Its screw back was stuck like it had been welded, but it finally gave way.

EF-503 on a flatbed scanner

Next morning I've bought one Renata 395 silver battery at the local market for EUR 1.40 and installed it without much hassle (you don't have to undo any screws on OS10, just gently pull on the elastic retainer lug with a flathead screwdriver and pop the batt in). Crown was in its 2nd position (fully out) so the movement couldn't start ticking yet. I've pressed the crown fully in (the moment of truth!) and my watch started running right away! Then I tightened the case back, did a chrono reset per factory instructions, set time and date and rejoiced... Chrono worked fine, although I needed factory instructions again to find out how to use the functions correctly. I guess the most probable cause of a dead quartz movement was a tiny particle that remained loose inside the movement after the "dirty" battery change and finally got stuck somewhere between the moving parts, stopping the very sensitive drivetrain. I guess I managed to blow it out using low pressure compressed gas from a can. I know that any pro watchmaker will cringe on mentioning of this "procedure", but I had nothing to lose and it solved the problem with little work. I have yet to check the long-term accuracy, although I don't think it was especially accurate back then while it was new (factory spec says ±20s/month is normal).

That same day I've buffed out one particularly annoying scuff on the mineral crystal (yes it's possible, but mind the heat!) and did some buffing on the stainless steel case, in both cases using Purol polishing paste and solid felt wheel on Dremel 300 rotary tool (in 3rd speed, pressing lightly, changing direction of passes). I suppose it was possible to achieve a mirror finish using chrome green but I decided to stick to a familiar compound even if it wasn't ideal for this purpose. I didn't bother to buff the case back, which is visible here:

This watch originally sported a black faux leather bracelet with white stitching (full model name is "EF-503L-1AV", module 2328). Rigid and uncomfortable OEM bracelet is long gone and new 20mm NATO gray nylon strap is already being shipped to my address. Oddly, this is my only watch that's completely silent: even my thick-cased Q&Q KW68 "Submariner" (powered by an ultra-accurate sample of Miyota 2035 quartz) ticks audibly...


Wears a bit bigger on 18mm strap, also black goes well with almost all imaginable outfits. Shown here with vintage Yugoslav Air Force leather jacket.