Unfortunately I can't lock out my TK40. I have to loosen the cap or the tail to the point it is almost falling off in order for it not to light when I turn it on. In that state it won't fit in the box and left in a drawer the cap or tail are bound to fall off.
there is something you can do to make a Spring have less throw, without altering anything permanentaly.
the back spring, on the cap to the carrier has what? 1/2" of total throw? and you NEED only say 1/4 " of total throw on the spring, to make a good connection still.
so you use a spring tightener.
i saw it used once on a Automobile, where they wanted the full force of the spring, but they never wanted the spring to go Loose, and extend its full distance.
they put some metal wrap or clip on the spring that binds the spring, only from going to a full extention, still allowing it to freely move within the wrap.
so, making sure you dont make any contact , to where it isnt supposed to go, you wrap a copper wire around say 4 coil lengths of the spring, leaving the top and/or bottom coil alone, and twist it down, like a bread twist tie, till the spring is the maximum desired height, then clip off the excess, then test it really well and over and over again, to insure it doesnt make any undesirable contact on the battery holder or light anywhere.
spring still moves, its shorter but you didnt cut anything, it will have the same strength within its now restricted movement, and the copper will bend and flex a few times without breaking and still keep contact if it gets in between the spring and the holder.
then after perfecting the spring throw ammount, and still insuring a good spring contact, far less twists will be needed to do a quick lockout.
if you go to sell it, just cut the "clip" off, and it is back to normal.
this works on excessive spring lengths on mags too, so you can get the threads started easier.
with the lockout you can stop any parasitic draw, but of course the disclaimer of taking the batts out of the holder (long time unused) might still apply, as they are in parellel with the other batteries when in the holder anyways.
