Hound Dog XPL Lego

[NH Lumens]

Well, it does have a Lumens Factory tailcap so I guess the "Lego" designation fits;




I received the Hound Dog XPL head yesterday and configured the light as planned;

• MD3 body
• XPL head
• LF UM00 Tritium Slotted Momentary Tailcap
• LF Z26 lanyard ring and finger loop
• Powered with a pair of NCR 18500A 2000 mAh flat top cells
• Run time on high - approx. one hour; run time on low - approx. 12 hours
• AOL = 6-13/16" (7" with switch boot projection)
• Weight with cells = 10.6 ounces

The XPL head uses a diffusion filter in back of the acrylic lens. Without the filter in place the candela is visually higher but the overall beam is not as smooth. I prefer leaving the filter in place.

The XPL is rated at 950 lumens and 44,000 candela. In visual comparison with my other lights, these specs appear to be correct. Compared to the M91T, the beam hot spot is not as wide but much brighter, and a little less light in the spill.

At about 70 lumens / 3,200 cd, the low setting is very useful: it's more than enough to walk the dogs or to take a stroll down the street after dark. In the photo the Malkoff markings on the body and head are aligned, this being a perfect reference for the low setting. It only takes about 1/8 turn to get high. I think I'll add a tritium tube on the tailcap to align with those markings to reference my preferred switch sensitivity.

The O-rings on the body serve as grip rings when holding the light with an ice pick grip, preventing the light from sliding forward in the hand when activating the switch with the thumb. At least for me they help immensely.

At seven inches long and 10.6 ounces, this is not what I would consider an EDC light. But it can ride in a cargo pants or coat pocket, so if I know that a light will be needed it can be carried on those occasions without much fuss. It fits in the right-front zippered pocket of my relaxed-fit Duluth Foreman's Pant without issue.

For its size, weight and performance, a good combination IMO.

 

[NH Lumens]

The LF UM00 Tailcap




This is a "twisty" tailcap based on the long-gone Surefire Z14/Z31 design. This no-shroud design is optimized for momentary operation, giving excellent control of the light using an ice pick grip;



The LF version uses a copper plunger, which when pressed contacts the rear edge of the body to complete the circuit. This makes for an extremely reliable and robust switch!

For constant-on operation, the tailcap is tightened to the body. What I like about this LF model is that the tailcap is easy to twist with one hand due to its larger diameter, and the grooves provide good traction for the thumb and index finger to operate;




Due to the design of this switch, the length of the cells directly impacts the compression of the springs, which in turn controls the pressure required to depress the switch. So the overall length of the cells must remain consistent to provide consistent pressure to activate the light. In this case with the use of the MD3 body, three CR123 batteries or two 18500 flat top cells are the same OAL and provide consistent switch pressure. Note: I find the plunger spring supplied by LF a little too soft so I change it out with one of these.

The downside of the unprotected cells from an operational standpoint is that I need to remain cognizant of run time. Due to the 5.5 - 12 voltage range of the head, the cells will reach maximum discharge level before there's any fall off in light output. The upside is that the light won't suddenly die in a time of dire need due to tripping the protection circuit.

I'm finding the low output of the XPL is really useful. According to the specs it produces at least 70 lumens on low, and candela calculates to about 3,200 which provides plenty of throw to illuminate objects 50+ feet away. Current draw on low is .15 amps, providing about 12 hours of run time on a set of 18500 2040 mAh flat top cells.

The XPL/MD3/UM00 combo is quickly becoming my favorite "full size" light!

 

[etc]

Go for the MD4 body, you will gain minimal length increase but double the runtime. I am exaggerating but you get the point.
But you already knew that.
Although I get it. MD3 you can EDC but MD4 is a real challenge.

 

[NH Lumens]

Go for the MD4 body, you will gain minimal length increase but double the runtime. I am exaggerating but you get the point.
But you already knew that.
Although I get it. MD3 you can EDC but MD4 is a real challenge.

I appreciate the suggestion!

For the way I use lights, keeping the size of the light manageable is a higher priority for me than run time. I can drop this very capable XPL Lego into a cargo pants pocket when needed where it rides mostly unnoticed (as does a MD4 with a M91T or B head), but due to its size and weight it's not a light I regularly carry ("EDC").

 

[etc]

I used to EDC a Surefire 9P loaded with a Malkoff. Or was a FiveMega 9P clone? Anyway, that fit into my pocket but barely. I moved onto to the MD2 format for EDC. And anything outside of EDC gets the MD4 body.

 

[Alaskantinbender]

The LF UM00 Tailcap

View attachment 49445


This is a "twisty" tailcap based on the long-gone Surefire Z14/Z31 design. This no-shroud design is optimized for momentary operation, giving excellent control of the light using an ice pick grip;

View attachment 49446

The LF version uses a copper plunger, which when pressed contacts the rear edge of the body to complete the circuit. This makes for an extremely reliable and robust switch!

For constant-on operation, the tailcap is tightened to the body. What I like about this LF model is that the tailcap is easy to twist with one hand due to its larger diameter, and the grooves provide good traction for the thumb and index finger to operate;

View attachment 49447


Due to the design of this switch, the length of the cells directly impacts the compression of the springs, which in turn controls the pressure required to depress the switch. So the overall length of the cells must remain consistent to provide consistent pressure to activate the light. In this case with the use of the MD3 body, three CR123 batteries or two 18500 flat top cells are the same OAL and provide consistent switch pressure. Note: I find the plunger spring supplied by LF a little too soft so I change it out with one of these.

The downside of the unprotected cells from an operational standpoint is that I need to remain cognizant of run time. Due to the 5.5 - 12 voltage range of the head, the cells will reach maximum discharge level before there's any fall off in light output. The upside is that the light won't suddenly die in a time of dire need due to tripping the protection circuit.

I'm finding the low output of the XPL is really useful. According to the specs it produces at least 70 lumens on low, and candela calculates to about 3,200 which provides plenty of throw to illuminate objects 50+ feet away. Current draw on low is .15 amps, providing about 12 hours of run time on a set of 18500 2040 mAh flat top cells.

The XPL/MD3/UM00 combo is quickly becoming my favorite "full size" light!

Very interesting combination. I wonder if or how the XPL head will run on a single cell on the 21700 body?

 

[NH Lumens]

Very interesting combination. I wonder if or how the XPL head will run on a single cell on the 21700 body?

I would use the 18650 Hound Dog on a single Li-ion cell, just bear in mind that you're stuck with the proprietary tailcap on the Malkoff 21700 body.

My favorite by far remains the Wildcat 18650 with a 5-degree diffusion lens installed on the MD2 body and LF tailcap;

 

[Johnny Ryall]

Very interesting combination. I wonder if or how the XPL head will run on a single cell on the 21700 body?

I run that set up all the time, I got the 18650 HD and WC and put them on that body usually for camping trips cause I know I won't need an extra battery if I also have smaller lights, you get good run time outa the 21700 body, as for carry I have an old open end belt holster that it can ride upside down in if needed, camping I'm in swim trunks a lot so that light just hangs in the van unless we're talking a walk at night.

 

[thermal guy]

I would use the 18650 Hound Dog on a single Li-ion cell, just bear in mind that you're stuck with the proprietary tailcap on the Malkoff 21700 body.

My favorite by far remains the Wildcat 18650 with a 5-degree diffusion lens installed on the MD2 body and LF tailcap;

View attachment 59131

I like me that! Think I might order me one.

 

[Monocrom]

Very nice Lego.

 

[Dicaeopolis]

I would use the 18650 Hound Dog on a single Li-ion cell, just bear in mind that you're stuck with the proprietary tailcap on the Malkoff 21700 body.

My favorite by far remains the Wildcat 18650 with a 5-degree diffusion lens installed on the MD2 body and LF tailcap;

View attachment 59131

What degree diffusion lens is in the Wildcat 18650 stock? ( I see on his site it is 10 degrees). I am guessing 5 degrees makes it diffuse less. What changes does the 5 degree diffusion lens make to the beam? Is there a hot spot at all? I like the lanyard ring too. Nice setup.

 

[NH Lumens]

What degree diffusion lens is in the Wildcat 18650 stock? ( I see on his site it is 10 degrees). I am guessing 5 degrees makes it diffuse less. What changes does the 5 degree diffusion lens make to the beam? Is there a hot spot at all? I like the lanyard ring too. Nice setup.

The WC comes from Malkoff with a 10-degree diffusion lens over the TIR lens, which turns a beam that is VERY similar to the HD into a 5k cd flood beam. The 5-degree diffusion lens splits the difference, making it into a smooth 20k cd beam without rings or artifacts.

 

[NH Lumens]

Just a heads up, I have this HD XPL head for sale in the flashlight parts forum.