Hound Dog 18650 XT V2

aznsx

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One last check - make sure the high/low switch is not loose, it needs to be fully tightened.

Thread slop certainly can be a factor and must be considered to the degree that it exists.

That aside though, in my opinion, and based on my limited experience, that "tightened" above should be emphasized even further. This design is not 'optimal' (which, in fairness, is often the case in the real world), but I think it can be made to function reliably; however that is dependent on the application of more torque when tightening the H/L ring in the head than I initially thought - quite a bit more. I found I had no tool handy that I could comfortably do it with, so I bought the Malkoff bespoke 'spanner' to use. Yes, I know it's somewhat expensive, but high quality tools usually are by their nature. I may only use it occasionally, but it's paid for itself. Note there's a hole through the body of the wrench to implement a 'T handle' of sorts. I just hand tighten with my hand set to 'max' torque wearing a nitrile-coated glove and that does it, but the point is that hole is there for a good reason. That ring must be VERY snug to have things function reliably. After properly torquing mine, it has functioned reliably. I'll see if that holds true with further use.
 

F89

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The high/low ring is potted in place on the Hound Dog. There is no tightening (or loosening to be done).
Mine appears to be tight as you'd expect.

My light is defective. I've investigated and trouble shot, and beyond.
From what I have gathered there is a problem with the high/low mechanism and/or driver (the spring loaded pin retracts and springs out as it should).

Whatever it turns out to be, a contact issue within the high/low mechanism or an issue with the driver, the problem won't be user serviceable.
 

aznsx

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The high/low ring is potted in place on the Hound Dog.
Roger that. I had no ideas some were 'affixed', as my experience is only with MD2. No time wasted though, as perhaps others might benefit from my experience.

You're on track, and I hope the situation is easily resolved to your satisfaction! Given all I've heard of the outfit, I'm fairly confident that will be the case.
 

NH Lumens

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Sorry, lost track that you are using the HD head, which indeed comes with the switch potted in place.

With the MD heads, a user installed switch can loosen unless it's cranked down tight.
 

F89

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At this stage I'll just have to wait to hear back. I've likely tried and checked all that they'll want to know, so I'd say it'll be a matter of the return and wait process (may be a while as I'm overseas).
 

md17

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So I have 3 newer Md bodies and I really think the supplies o rings could be thicker or tighter so they don't spin when using the high low switch. Has anyone tried a bigger o-ring. If so, what size?
 

mk2rocco

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So I have 3 newer Md bodies and I really think the supplies o rings could be thicker or tighter so they don't spin when using the high low switch. Has anyone tried a bigger o-ring. If so, what size?
I don't recall the size I use, but all my Malkoff bodies have a thicker oring to make turning the head harder.
 

md17

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At this stage I'll just have to wait to hear back. I've likely tried and checked all that they'll want to know, so I'd say it'll be a matter of the return and wait process (may be a while as I'm overseas).
Hello. Have you made any progress on this issue? I believe I just ran into the same problem, however I am convinced the issue is not the head, but rather the body. I bought an old style md3 body and was using a hound dog xpl head and had very erratic hi/lo operation. I didn't have any issues with 2 other types of new style bodies. I spoke to Gene and he made some suggestions that seemed to help. Taking it a step further and reading more than I ever thought was possible about o-rings, and getting suggestions from other members here, I think I found a plausible solution…

So what Gene suggested was to remove oxidation with high grit sandpaper. I used 400 grit with a layer of rubbing alcohol on a flat surface, and very carefully "wet sanded" the top contact surface until I saw a little material come off. There's no doubt it was oxidized from sitting in a warehouse for a long time. That fixed most of the issues.

He also suggested to use Deoxit Gold on the hi/low contact spring. I Purchased it on Amazon for $7. I do not know what difference this made, but it can't hurt and it was only $7.

DeoxIT® gold Mini-Brush Applicator, 100% Contact Conditioner, 1.6mL - G100L-16BX https://a.co/d/8acMX70

So, I still had thread wobble when loosened and the yellow Teflon tape made that better, but I do not want to have to replace that every several days as I can't leave things alone, so I will definitely mess with the flashlight and change the heads, Swap batteries (ocd adhd blah blah blah I've heard it all)

So, I ordered 3 types of o rings with a hardness rating of 90 versus the typical 70 which I am waiting to get in the mail.
They have the following measurements:
Inner Diameter: 15/16
Outer Diameter:1-1/8
3/32 cs. I am assuming that means circumference

But while at Home Depot I also grabbed standard off the shelf #105 o rings. No hardness rating details were provided, but they measured:

Inner diameter: 3/4 inch
Outer diameter: 1 inch
Cs:1/8

These work great and make the head almost as tight as if it was wrapped with teflon, but without being wrapped with Teflon. I think the problem with the standard size o-ring that comes from the factory is that they slide when turning the head and these new ones are much tighter, but can still be removed with a plastic pick tool.

Hopefully this helps and it not something you may have already tried. IMG_5486.jpeg
 

F89

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Ok, so I've got this sussed now. Didn't think I was going to get there but I've sorted it out.

I made contact with Gene, who was prompt with communication (via email) and offered trouble shooting advice. It quickly became evident that I wasn't getting anywhere so he sent me a new head with body that he'd prepared.
Gene was certain that it was the oxidisation of the body contact surface causing the issue. The new body appeared to be pre sanded.
The new head worked initially (on both new and old body) but I was still getting the flicker whilst rotating, although it would settle on a consistent low when stationary.
After a while it started doing what the old one did, an inconsistent low which would either flicker, be a very low low or not come on at all.
The first head got to the point where it would hardly light up on low at all, as in likely not light at all.

At this point I was certain the body had nothing to do with the problem and that the pin/resistor was the issue.
I tried Deoxit (red cleaning solution and yellow conditioner), this achieved nothing.
I was certain there was a bad batch of these heads. So I went away and thought about it.

I didn't want to hassle Gene so close to Christmas so I thought I'd give up on the project for another couple of weeks or so.

Then I thought some more. No problem with my old Houndog, but it runs on lower amps and higher voltage.
This made me think of trying the last thing that I hadn't bothered with so far as I was convinced the problem wasn't the body or oxide layer.
I rigged up some wires and connected them to a battery and the head. No issue with low operation. Not a flicker, a moonlight, or a fail.
Interesting, I thought to myself.

I then took the body and lightly sanded it with 2000 grit (much smoother finish than Gene had done). I wasn't stopping there though, so I then polished it with a Dremel. Nice and shiny, smooth.

Works like an absolute charm! No flicker whilst rotating even. Consistent and reliable low operation every time.

This problem will be more likely with high powered single cell models with the high/low switch. With such a tiny surface on the little, rounded brass pin, if that contact surface isn't good then, like me, you'll likely have issues.

On another note regarding the head wobble in low position. The new body has way less wobble to the point I'm happy to use it without plumbers tape. There is still some play, but nothing major like I had with the old style body.

Some other points of interest. The replacement head has a less than optimal focus, the first one is much better. I'll be sticking with the first head now that I've solved the riddle.

I'm really happy with this light and relieved that I won't be looking for an alternative.

I have to say that Gene was excellent regarding his attention, solutions, options and prompt responses. Malkoff devices provided me with the service and support I would like to expect but in practice find less often.
I'm sure that if I hadn't sorted out the problem that Gene would have gone through the motions to work out what's next.
Thanks Gene.
 

md17

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Ok, so I've got this sussed now. Didn't think I was going to get there but I've sorted it out.

I made contact with Gene, who was prompt with communication (via email) and offered trouble shooting advice. It quickly became evident that I wasn't getting anywhere so he sent me a new head with body that he'd prepared.
Gene was certain that it was the oxidisation of the body contact surface causing the issue. The new body appeared to be pre sanded.
The new head worked initially (on both new and old body) but I was still getting the flicker whilst rotating, although it would settle on a consistent low when stationary.
After a while it started doing what the old one did, an inconsistent low which would either flicker, be a very low low or not come on at all.
The first head got to the point where it would hardly light up on low at all, as in likely not light at all.

At this point I was certain the body had nothing to do with the problem and that the pin/resistor was the issue.
I tried Deoxit (red cleaning solution and yellow conditioner), this achieved nothing.
I was certain there was a bad batch of these heads. So I went away and thought about it.

I didn't want to hassle Gene so close to Christmas so I thought I'd give up on the project for another couple of weeks or so.

Then I thought some more. No problem with my old Houndog, but it runs on lower amps and higher voltage.
This made me think of trying the last thing that I hadn't bothered with so far as I was convinced the problem wasn't the body or oxide layer.
I rigged up some wires and connected them to a battery and the head. No issue with low operation. Not a flicker, a moonlight, or a fail.
Interesting, I thought to myself.

I then took the body and lightly sanded it with 2000 grit (much smoother finish than Gene had done). I wasn't stopping there though, so I then polished it with a Dremel. Nice and shiny, smooth.

Works like an absolute charm! No flicker whilst rotating even. Consistent and reliable low operation every time.

This problem will be more likely with high powered single cell models with the high/low switch. With such a tiny surface on the little, rounded brass pin, if that contact surface isn't good then, like me, you'll likely have issues.

On another note regarding the head wobble in low position. The new body has way less wobble to the point I'm happy to use it without plumbers tape. There is still some play, but nothing major like I had with the old style body.

Some other points of interest. The replacement head has a less than optimal focus, the first one is much better. I'll be sticking with the first head now that I've solved the riddle.

I'm really happy with this light and relieved that I won't be looking for an alternative.

I have to say that Gene was excellent regarding his attention, solutions, options and prompt responses. Malkoff devices provided me with the service and support I would like to expect but in practice find less often.
I'm sure that if I hadn't sorted out the problem that Gene would have gone through the motions to work out what's next.
Thanks Gene.
So I received more o rings in the mail and I have come to the conclusion that the best size that eliminates 90% of head wobble when on low mode is:
Inner diameter: 3/4 inch
Outer diameter: 1 inch
Cs:1/8
 

F89

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Joined
Mar 15, 2014
Messages
1,413
So I received more o rings in the mail and I have come to the conclusion that the best size that eliminates 90% of head wobble when on low mode is:
Inner diameter: 3/4 inch
Outer diameter: 1 inch
Cs:1/8
That could be useful on my old style (knurled) MD2.
The amount of wobble I'm getting with the new style body isn't worth worrying about for me.

Edit:

After using my old Hounddog XML2 then playing (comparing) with the XT, I've gone back to using a little plumbers tape on the XT.
The old Hounddog is perfect with no tape, only the tinniest, insignificant amount of play. The new body on the XT is way less wobbly than the old one and pretty well fine, but with a little tape it has zero play and a good, smooth action I can still change modes with one hand in either position.

The light hasn't skipped a beat since polishing the body.
I haven't emailed Gene back yet, I'll give him a shout after we're well clear of Christmas and New Year's.
 
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