Converting Surefire KX4 head to accept P60 drop-in

[Flashlike]

If I remove the innards of a Surefire KX4 LED head can I use a P60 drop-in (or better yet a Malkoff M61 drop-in)?
Or are there additional modifications I would need to do before the drop-in would fit and work properly?
I found this "tutorial" online how to disassemble and remove the components on the KX4 head:

Tutorial: Disassemble Surefire KX4 Head - LumenZilla

Surefire KX4 is a great LED conversion kit for P60 flashlights. I want to be able to upgrade the LED but unfortunately the head is not designed to be taken apart. Read my successful method below.

lumenzilla.com

Not a whole lot to doing that, actually. Basically a matter of removing the bezel then everything comes out the front side.

 

[yazkaz]

If I remove the innards of a Surefire KX4 LED head can I use a P60 drop-in (or better yet a Malkoff M61 drop-in)?
Or are there additional modifications I would need to do before the drop-in would fit and work properly?
I found this "tutorial" online how to disassemble and remove the components on the KX4 head:

Tutorial: Disassemble Surefire KX4 Head - LumenZilla

Surefire KX4 is a great LED conversion kit for P60 flashlights. I want to be able to upgrade the LED but unfortunately the head is not designed to be taken apart. Read my successful method below.

lumenzilla.com

Not a whole lot to doing that, actually. Basically a matter of removing the bezel then everything comes out the front side.

I strongly oppose taking the KX4 apart. AFAIK the KX4 host is slightly shorter than the native Z44 such that a standard D26 module may not be able to fit in. Your discretion is advised.

 

[WarriorOfLight]

If I remove the innards of a Surefire KX4 LED head can I use a P60 drop-in (or better yet a Malkoff M61 drop-in)?
Or are there additional modifications I would need to do before the drop-in would fit and work properly?
I found this "tutorial" online how to disassemble and remove the components on the KX4 head:

Tutorial: Disassemble Surefire KX4 Head - LumenZilla

Surefire KX4 is a great LED conversion kit for P60 flashlights. I want to be able to upgrade the LED but unfortunately the head is not designed to be taken apart. Read my successful method below.

lumenzilla.com

Not a whole lot to doing that, actually. Basically a matter of removing the bezel then everything comes out the front side.

If you would like to use a KX4 for P60 dropins you must modify the inner of the head.

The easiest way is seeking for a Z44 and use this Z44 with the Malkoff dropin, and let the KX4 in the way it is.

 

[yazkaz]

If you would like to use a KX4 for P60 dropins you must modify the inner of the head.

The easiest way is seeking for a Z44 and use this Z44 with the Malkoff dropin, and let the KX4 in the way it is.

Such modification, does it involve additional machining to the inside of the KX4 host? If so then juet leave it as is. Meanwhile the only possible way to upgrade the KX4 is via LED swap.

BTW the Malkoff dropin actually does not work all great with the Z44, as its slightly elongated heatsink design means the gap between the bezel (head) and the body is unavoidable (even though good electrical conductivity is guaranteed).

 

[WarriorOfLight]

Such modification, does it involve additional machining to the inside of the KX4 host?

Yes that is necessary. For better understanding. When you remove the bezel of the KX4 the "dopin" will fall apart, means reflector and LED / Electronics part.
Also the lens has a different size in compare to the Z44. If I remember correctly the dropin parts are needed to keep the lens on the correct position.
The KX4 is not like a Z44 bezel. Even if it looks like it from the outside. Therefore again, my recommendation is using a Z44 or something compatible (liky Cryos Cooling bezel, ...).

Btw. this gap problem you mentioned exist with a lot dropins, that is also the case if i.e. the overardy P60 dropins are used, or even the cheap Solarforce ornot that cheap Sportac.

 

[yazkaz]

Yes that is necessary. For better understanding. When you remove the bezel of the KX4 the "dopin" will fall apart, means reflector and LED / Electronics part.
Also the lens has a different size in compare to the Z44. If I remember correctly the dropin parts are needed to keep the lens on the correct position.
The KX4 is not like a Z44 bezel. Even if it looks like it from the outside. Therefore again, my recommendation is using a Z44 or something compatible (liky Cryos Cooling bezel, ...).

Btw. this gap problem you mentioned exist with a lot dropins, that is also the case if i.e. the overardy P60 dropins are used, or even the cheap Solarforce ornot that cheap Sportac.

No offence but perhaps the sadder thing to note is the quality of flashlight enthusiasts these days (especially the younger generation ones) which are declining from era to era. In fact this is the first time I hear about some dude trying to gut a KX4 host to accept D26 modules -- a question that nobody would ever ask before. Why? Because older (and more experienced) folks know it's just not possible, knowing that the completely different design (and dimensional discrepancy) on the KX4 construction means it's not to be treated as a Z44 alternative. And if Z44s could still be procured easily (back then), then why bother breaking a KX4 in the first place?

Yet some inexperienced "Joes" would only judge a flashlight component by face value, and think that any mod could be possible. Sooner or later some dudes might even ask, "How am I going to replace a 6PX's internals and drop in a D26?" Very said indeed.

As for the bezel/body gap, many seem to live through it, but just not everyone (myself included). This is a challenge to some mfyers like Lumens Factory in that the D26 module's (ahd heatsink's) height is to be maintained at optimal level, for exact fit inside the C-head setup without yielding the dreaded gap, while ensuring effective electrical conductivity is guaranteed within the flashlight setup.