QTC Puck for Surefire C/P/Z Lights

[Tofty]

Have you ever wanted variable output on your Malkoffs or other single mode P60 drop-ins?
Yeah me too, that's why i set out to try and make a QTC puck that fits into the tailcap without having to modify the light.
I wasn't able to acheive this but i came close enough....for now.

 

 

The puck is made from delrin plastic and brass with the anti-rotation pins made from carbon fibre as they have to be quite narrow, strong and insulating (i just discovered that carbon fibre can be quite electrically conductive but due to the way i glued the pins into the top brass plate, the low contact area on the bottom plate and the relatively low conductivity of the pins due to their thick resin outer surface it turned out they don't interfere with the pucks operation).
I used three QTC pills to decrease the stress on any one pill and to reduce the amount of rotation needed to go from off to highest output. The pills are also isolated from rotaion on their faces which should reduce wear and tear as the pills can become fragile.
I added a bypass screw in the puck's centre to allow the bypassing of the QTC to achieve 100% output or if the qtc fails completely.
The o-ring stops the puck from coming apart when changing batteries and the puck is easily disassembled without needing any tools.

The installation requirements for this puck are that the Z44 (or similar) tailcap has a mcclicky switch convertion with the spring cut down leaving the spring retention plate as the contact face and that some of the anodising is removed from the threads inside the tailcap to create an electrical pathway. THe puck did work in my MD2 with no modifiction but it's mcclicky spring got bent while tightening the tailcap so not wholly successful.
With the puck installed the cap will sit about 2mm further out than normal which leaves the tailcap's edge quite close to the torch bodies o-ring.

This puck is an evolution from my original QTC system i made for my Ti Dive torch after learning some important lessons.
It does not put increasing pressure on the batteries when tightened, instead compression occurs between the torch middle section's base and the tailcap switch with the batteries lightly pressed against the drop-in's spring with unchanging force.

This puck does not fit into the G series bodies and even if it did it still wouldn't work os it needs a metal tailcap.

I'll do an operational video when i'm fully happy with the pucks performance.

[jzmtl]

Want one! 

[Styerman]

Do want , sadly my remaining Surefire is an E series .

Chris

[Tofty]

I like the E series but the bodies really too small to mod (bore) and compared to the P60 hosts like the P/Z/Cs they're not as popular.
For this puck to work in the real world it will need a tailcap designed around it so stay tuned.