Surefire Z32 Bezel

Surefire 6P with Surefire Z44 bezel (top), Surefire 6P with Surefire Z32 bezel (bottom)

The Surefire Z32 bezel was used on the Surefire M2 flashlight and currently on the Surefire M951XM07 Millennium® Universal WeaponLight. The main design function of the bezel is to isolate the incandescent lamp assembly from weapon recoil shock. Since the shock mechanism reduces the heat dissipation ability of the bezel, I use aluminum shims or copper tape around the LED drop-ins to help dissipate the heat through the flashlight body.

The Surefire 6P, is to me, what a flashlight looks like (though I have moved on from incandescent lamp assemblies to LED drop-ins, such as this modified Malkoff M61). The stock Surefire 6P is 5.20″ (132 mm) long and the bezel diameter is 1.25″ (~32 mm). I like the current design of the Surefire Z32 bezel as opposed to the original design with the vented ribs. The Z32 bezel is about 1/4″ larger in diameter and about 3/8″ longer than the Z44 bezel that is standard on the 6P. With a Z32 bezel on a 6P body, it looks even more like a flashlight.

Surefire E2E Flashlight Mods

I bought a Surefire E2E because it was a good deal. I didn’t realize until I received it how much smaller it is in comparison to the Surefire 6P flashlights that I have. It’s about the same size as my JETBeam Jet-I Pro.

The E2E uses an incandescent lamp, the Surefire MN03 lamp assembly, with an output is 60 lumens. The output seemed a little low so I started looking for ways to make it brighter.

Fivemega, over at candlepowerforums.com makes two nice incandescent options for the E2E, a bi-pin socket and a Mini Turbo Head.

I’d rather use LEDs and I found that Veleno Designs makes a good option fits in the E2E head. The Veleno Designs E Series LED drop-in is machined from brass, has great heat sinking and uses a Cree XP-G LED. I ordered a 3 mode cool white model and while the output was great, the tint was a little green. The manufacturer said that most people order a neutral tint so they don’t have that problem.

I decided to order some neutral tint Cree XP-G LEDs from DigiKey to replace the LED. After I soldered the LED to the board, I trimmed the board with a Dremel so it was a little larger than 3.5mm x 3.5mm, so it would fit on the Veleno pedestal. It still had a green tint.

In a few discussions on cpfmarketplace.com, it was theorized that the E2E reflector was causing the green tint and it was a lottery whether the factory reflector had the green tint. Instead of buying a new bezel/reflector, I tried re-silvering the reflector. The tint was still green.

Because of the work involved in putting another LED on the Veleno drop-in, I decided to try to find a deal on a Surefire KX2 LED Conversion Head. When I received it after a week, the tint on my new KX2 was also green. I had also taken a very long way to get to a E2L Outdoorsman.

Determined to get the light I wanted, I disassembled the KX2 using a heat gun to release the ample amount of glue that Surefire used on the threads to hold the head together. I unsoldered the leads from the LED board, removed the two hex screws holding the LED board to the drop-in and pushed the LED board out.

I then unsoldered the old Cree XR-E and reflowed soldered in a new Cree XR-E (R2 bin). I reassembled the KX2 using Arctic Silver 5 Thermal Compound underneath the LED board and when I first tried the light the hot spot was off center. I centered the LED and because the threads on the bezel that holds the Surefire Total Internal Reflection (TIR) lens were no longer glued, I was able to focus the beam to a perfect hot spot. And finally I have a neutral tint.

Now that the KX2 is open, I could use another driver, maybe try a McR-19XR reflector or an XP-G LED; but it’s been a long road to get here, so maybe I’ll wait a while.

Soldering High Brightness LEDs

A year ago I saw this Youtube video where Steve Dahl at DigiKey demonstrates a method of soldering high-brightness LEDs to a Metal Core Printed Circuit Board (MCPCB) using a heat gun.

Though I’ve seen an electric skillet used for reflow soldering, I decided to try using the above technique when I wanted to replace an LED on a drop-in. I ordered some neutral Cree XP-G LEDs from DigiKey, some 16mm circuit boards and some LodeStar solder paste.

I don’t have an expensive heat gun – just one for removing paint. I thought if I used my infrared thermometer, I could measure the temperature at the tip of the gun and when it was maintaining the correct temperature, I would hold the board/LED in the heat.

Reflow Soldering LEDs

I put dabs of solder paste on the contact pads where the LED would be soldered and placed the LED on the pad. It doesn’t need to be precise because the solder will only flow onto the contact pads.

The Cree XP-G specs (PDF) have 215 degrees C (~419 degrees F) for Peak/Classification temperature. When my thermometer read that, I put the board in the heat. (In the video, they use 600 degrees, which seems way out of spec and may be the reason the board turned brown). In a few seconds the paste melted and the LED centered itself, just like in the video. I immediately turned the heat off and kept the fan running to cool the board.

In the photo, the bottom board has been soldered. The upper left board shows the amount of paste I used. The upper right board has the LED on it before soldering.

A Brighter 74 Lamp

74 LED Lamp T1-3/4I was having trouble seeing the turn signal indicator in my 1979 Alfa Romeo Sprint Veloce. Though I am relatively old if you’re young, I didn’t want to look that way driving down 101 with my turn signals on.

When the original thermal turn signal flasher gave up, I replaced it with an electronic flasher. With the engine off I can hear it clicking very clearly – I can’t hear it while the engine is running unless the fuse box is open and I stick my head next to it – not a good driving position since the fuse box is just above the floor.

Probably 40 years ago, I made a turn signal amplifier using a 555 integrated circuit and a Mallory Sonalert. It was annoying, sort of like the beepers that some vehicles have when they’re backing up.

Alfa Romeo Alfetta Tachometer

I started looking for a brighter lamp for the turn signal indicator that is mounted below the tachometer. The OEM lamp is a 74 Miniature Indicator Lamp – 14 Volt – T1-3/4 Sub Mini Wedge Base. In bright sunlight, it’s difficult to see if the OEM lamp is flashing. I found an LED replacement lamp that is essentially a SMT LED stuck on the end of a plastic tube with a diode and resistor to drop the voltage. It had the necessary wedge base. I had to file the sides down a little so it would fit in the lamp holder, but it was worth the $5.50. It’s bright enough to see in direct sunlight, but not so bright that it’s too annoying at night.