Misc. tips using the triple XPG V3 in a Surefire 918FA.
1) I had to make a ring out of 12ga copper wire to put between the lamp assembly and the "flashlight" body before it would work (trick seen elsewhere on CPF but I don't have a source).
2) The "shock" head on the 918FA doesn't put enough pressure on the lamp assembly for it to make positive contact after sitting over night. I did purchase the spacer, and that would probably work, but it crushes the shock material to the point I suspect it would probably deform over time.
Short term I stuck a G2 head on there and that works fine, so I've ordered a Z44 to replace the shock head.
3) The 918FA is a 3x123a configuration. Since it holds two cells in the "tube", or body of the light, and one cell in the fore-arm, it isn't really practical to go to a bored configuration. Since it doesn't look like I can run 3x123a, I decided I would go with 2x17670. Of course to get there I need to extend, so I ordered an A19. I guess I could have replaced the existing 2x123a length body with a 9P body and have one-piece, but the A19 is a fair amount cheaper.
Later, I found Dereelight has an extention tube that might work and is cheaper, but I had already ordered the A19 and I don't know for sure if the Dereelight part would mate correctly. It is EXT500 and $10. Shipping is like $2, so it is a good deal. I actually ordered a full CL1H V4 host with tubes, so I'll see if it fits when it gets here.
4) I had to order some protected 17670 cells because of #3.
So this was a bit more painful (and more expensive!) that I had anticipated, but now the 918FA is as bright as it deserves. Quite an upgrade from 200lm and 19 mins. runtime on 3 cells!
-john
Edit: One remaining outstanding item is my concern about recoil using the 2x17670s. Surefire actually sells a "battery pack" of 3x123a cells shrink wrapped together with some sort washer between the cells to prevent crushing. I figure I might need to do something like that to prevent the buttons (and possibly the protection circuits) from being crushed. If anyone has ideas about this, I'm all ears. Thanks.
1) I had to make a ring out of 12ga copper wire to put between the lamp assembly and the "flashlight" body before it would work (trick seen elsewhere on CPF but I don't have a source).
2) The "shock" head on the 918FA doesn't put enough pressure on the lamp assembly for it to make positive contact after sitting over night. I did purchase the spacer, and that would probably work, but it crushes the shock material to the point I suspect it would probably deform over time.
Short term I stuck a G2 head on there and that works fine, so I've ordered a Z44 to replace the shock head.
3) The 918FA is a 3x123a configuration. Since it holds two cells in the "tube", or body of the light, and one cell in the fore-arm, it isn't really practical to go to a bored configuration. Since it doesn't look like I can run 3x123a, I decided I would go with 2x17670. Of course to get there I need to extend, so I ordered an A19. I guess I could have replaced the existing 2x123a length body with a 9P body and have one-piece, but the A19 is a fair amount cheaper.
Later, I found Dereelight has an extention tube that might work and is cheaper, but I had already ordered the A19 and I don't know for sure if the Dereelight part would mate correctly. It is EXT500 and $10. Shipping is like $2, so it is a good deal. I actually ordered a full CL1H V4 host with tubes, so I'll see if it fits when it gets here.
4) I had to order some protected 17670 cells because of #3.
So this was a bit more painful (and more expensive!) that I had anticipated, but now the 918FA is as bright as it deserves. Quite an upgrade from 200lm and 19 mins. runtime on 3 cells!
-john
Edit: One remaining outstanding item is my concern about recoil using the 2x17670s. Surefire actually sells a "battery pack" of 3x123a cells shrink wrapped together with some sort washer between the cells to prevent crushing. I figure I might need to do something like that to prevent the buttons (and possibly the protection circuits) from being crushed. If anyone has ideas about this, I'm all ears. Thanks.
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ing for a very good thread: the idea of actually really using these bad boys.
Just got my TorchLAB L1N XPG the other day. This is just completely awesome, flawless beam, perfect color tint with the 4500K Neutral XPG. It lights up my whole front yard. I'm really impressed, worth every penny. Words just can't describe it!