The Lion Heart is a well machined and feature rich light of surprisingly few components.
The simplicity is great but I wanted to tweak the design a bit in terms of assembly and sealing. Due to some variations in dimensions, my light initially would not provide a seal with the battery tube against the combination seal/ retainer O-ring that seats against the PWM PCB. My light came with a Belleview washer and one of my two Pila batteries was not long enough to make electrical contact. These issues have been addressed with an additional larger sized O-ring as well as a coiled contact spring now being provided. I went ahead and took it upon myself to do some modifications:
1) I exchanged the TW0K Luxeon with a TY0L bin LED. This Y bin has a current of just over 1 amp at 4.2 Vf and a current of about 400 mA at 3.6 Vf. I used Arctic Alumina Epoxy to bond the star to the bulkhead as the reflector no longer contacts and holds the star against the bulkhead.
2) I used insulated lead wires to the LED from the PCB and provided an isolated ground contact for the battery tube lip via a open ring of brass that was soldered to the PCB after removing solder mask from the perimeter of the PCB)
3) I put some small dabs of AA epoxy on the PCB ledge in the areas where the PCB has "break away" "teeth" and this epoxy will retain the PCB as well as provide anti-rotation of the PCB when the battery tube contacts the ground ring.
4) I cut an O-ring groove behind the threads of the battery tube and machined a mating bore/ face seal counter bore in the head to receive the O-ring. Compression of the O-ring occurs prior to the battery tube lip making electrical contact with the ground ring. The electrical path of the ground can be opened with the seal still in function.
5) I formed my own coiled battery contact spring from a silver plated spring I had on hand.
6) I installed a titanium belt clip with lanyard bail for aid in carry and securing the light.
7) I machined a McR-27 reflector to allow it to drop into the head of the Lion Heart and align the focal point with the LED. The reflector extends beyond the head less than the IMS reflector and I found that adding an additional O-ring behind the window more than makes up the gap and seems to allow for a good compression and seal of all areas in and around the bezel. On a partially discharged Pila, I measured 2300 lux from the combination of the TY0J LED and this reflector on full duty level.
