leukos
Flashlight Enthusiast
I had several unused P60 bulbs laying around and was wondering how I could use them without going through $$ of primaries. I also noticed they are selling relatively cheap in the Marketplace, so I thought it would be ideal to have a 4x AA host to run them in guilt free. I have always thought the Princeton Tech 40 was a good candidate for modding. I didn't notice any threads in the archive on this, so I thought I would give it a go. I used an older PT 40, so I have no idea if the newer versions have the same internals. Test host:
First thing I did was remove the lamp assembly.
With a pair of needle nose pliers, remove the negative terminal screw as shown (twists out):
Drill a third hole (as shown on the far right) to make contact with the outer spring of the P60. Insert a screw slightly longer than the screw removed into the drilled hole:
Should look something like this when finished:
The screw should come out in a place that could make contact with the outer spring on the P60 lamp (right side of picture). Use a dremel to remove the plastic cylinder in the middle of the module as shown. Place epoxy over the end of the positive screw (left side of picture) to prevent contact with the outer spring on the P60 lamp:
Purchase a 3/4 inch PVC end cap at a hardware store ($.36 at Menards). Cut off a ring 3/8 inch deep:
3/8" ring with P60:
This ring keeps the P60 centered in the bezel:
Add some glow paint to the ring if you wish (drill holes for tritium, whatever). I get about 1.5 hours runtime on a set of eneloops. I have run the P60 for 3 hours straight, there is no damage to the plastic lens. The twist on/off function still works somewhat with the mod, but may not depending on your screw placement. Enjoy!
First thing I did was remove the lamp assembly.
With a pair of needle nose pliers, remove the negative terminal screw as shown (twists out):
Drill a third hole (as shown on the far right) to make contact with the outer spring of the P60. Insert a screw slightly longer than the screw removed into the drilled hole:
Should look something like this when finished:
The screw should come out in a place that could make contact with the outer spring on the P60 lamp (right side of picture). Use a dremel to remove the plastic cylinder in the middle of the module as shown. Place epoxy over the end of the positive screw (left side of picture) to prevent contact with the outer spring on the P60 lamp:
Purchase a 3/4 inch PVC end cap at a hardware store ($.36 at Menards). Cut off a ring 3/8 inch deep:
3/8" ring with P60:
This ring keeps the P60 centered in the bezel:
Add some glow paint to the ring if you wish (drill holes for tritium, whatever). I get about 1.5 hours runtime on a set of eneloops. I have run the P60 for 3 hours straight, there is no damage to the plastic lens. The twist on/off function still works somewhat with the mod, but may not depending on your screw placement. Enjoy!
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