Malkoff in Leef contact problem? Here's a cheap easy fix!

dhwfd46

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Having recently acquired 2x18650 & 1x18650 Leef tubes to use with Malkoffs, I quickly found out I had contact issues.

The issue stems from the difference in the bore between the Leef and Surefire tubes. The SF, which the Malkoff was designed for, uses a tapered bore where the lamp module drops in. The Leef has a straight bore which can result in insufficient contact surface for reliable operation.
IMG%5D


I made a copper contact ring out of a piece of 12 ga solid copper wire. Just wrap it around the module to rough shape it, then trim and work it till it will fit down in the bore. 14 ga will work too; its easier to work with but the fit is tighter with 12 ga and it holds it's shape. I left a gap in the ring to accomodate the small glob of solder on the side of the module. If you're going to use 12 ga you need to form it so it fits snug against the bore, or you'll have a gap when you screw the bezel down.

http://i132.photobucket.com/albums/q10/dhwfd46/DSCF0865.jpg

IMG%5D
Here's the contact ring itself:http://i132.photobucket.com/albums/q10/dhwfd46/DSCF0867.jpg
IMG%5D

I've also read many complaints about tailcap contact. Keep these points in mind. The twisties make contact on the end of the tube, so you may need to clean a little anodization off the end of the tube. Also, the twistie doesn't have electrical continuity until it makes physical contact with the tail end of the tube. This is why the light doesn't come on until it's screwed down tight. If you're using a tailcap that makes contact through the threads, then you need to clean the threads off so you have continuity. The SF threads arent anodized.
 
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LukeA

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Having recently acquired 2x18650 & 1x18650 Leef tubes to use with Malkoffs, I quickly found out I had contact issues.

The issue stems from the difference in the bore between the Leef and Surefire tubes. The SF, which the Malkoff was designed for, uses a tapered bore where the lamp module drops in. The Leef has a straight bore which can result in insufficient contact surface for reliable operation.

I made a copper contact ring out of a piece of 12 ga solid copper wire. Just wrap it around the module to rough shape it, then trim and work it till it will fit down in the bore. 14 ga will work too; its easier to work with but the fit is tighter with 12 ga and it holds it's shape. I left a gap in the ring to accomodate the small glob of solder on the side of the module. If you're going to use 12 ga you need to form it so it fits snug against the bore, or you'll have a gap when you screw the bezel down.

DSCF0865.jpg


Here's the contact ring itself:
DSCF0867.jpg


I've also read many complaints about tailcap contact. Keep these points in mind. The twisties make contact on the end of the tube, so you may need to clean a little anodization off the end of the tube. Also, the twistie doesn't have electrical continuity until it makes physical contact with the tail end of the tube. This is why the light doesn't come on until it's screwed down tight. If you're using a tailcap that makes contact through the threads, then you need to clean the threads off so you have continuity. The SF threads arent anodized.

You had some excess characters around your images.
 

etc

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I made a copper contact ring out of a piece of 12 ga solid copper wire. .

I had that issue with M60 and Leef 2x18650... but not 18500 interestingly enough. I used alum foil to fix it but need a permanent fix such as yours.

Stupid question, but where do you buy solid copper wire in small quantities? Some kind of electronics/audio store? Hardware perhaps? Home Depot?

I see Ebay has some but in large quanties, like 200 ft..
 

etc

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I have a different issue with Leef, it lacks enough thread vs. Surefire 9P body or FiveMega body and thus the Z41 doesn't screw in as far and requires just a bit more pressure to activate the instant-on.

FiveMega 2x18500 + Z41 TC is easiest to activate, even easier than stock SF 9P body..
 

dhwfd46

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You can get single strand 12 or 14 ga solid cu wire at Lowes for about 15 cents a foot. You can do the wire trick with the tailcap too, but you have to use 14 ga, 12 won't fit. This effectively makes your tail threads a little longer.

You could probably use an outer spring that's been discarded from one of the chinese drop-ins, so it will fit in a Surefire's taper bore, to fix the front end contact issues in a Leef tube as well.
 

etc

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I don't have a contact issue with the tailcap, it does turn on, just with a bit more pressure than I would like. It needs to be screwed in another turn but it's out of thread.
FiveMega is closer to spec in this regard.

I think I will just use Leef bodies with Z48 and Z49 tailcaps, which work wonderfully, and keep the Z41 for FiveMega bodies.
 

Bullzeyebill

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I don't have a contact issue with the tailcap, it does turn on, just with a bit more pressure than I would like. It needs to be screwed in another turn but it's out of thread.
FiveMega is closer to spec in this regard.

I think I will just use Leef bodies with Z48 and Z49 tailcaps, which work wonderfully, and keep the Z41 for FiveMega bodies.

Do the wire trick as suggested for tailcap and you will have very good contact without the pressure you are requiring. I use a spacer (washer) in the tailcap when the batteries are too long for the tube, like when using two protected cells. This works good with some of the older SF bodies that are shorter than current.

Bill
 

etc

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Do the wire trick as suggested for tailcap and you will have very good contact without the pressure you are requiring. I use a spacer (washer) in the tailcap when the batteries are too long for the tube, like when using two protected cells. This works good with some of the older SF bodies that are shorter than current.

Bill

I thought the wire trick was for the module, not the tailcap.

Do you have pics of the spacer (washer) you are using? What's it made of?

Are you sure the problem is that the cells are too long for tube? I thought it was the fact that the tailcap doesn't screw far enough.
 

Bullzeyebill

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I thought the wire trick was for the module, not the tailcap.

Do you have pics of the spacer (washer) you are using? What's it made of?

Are you sure the problem is that the cells are too long for tube? I thought it was the fact that the tailcap doesn't screw far enough.

Post 6 also mentions tailcap fix with wire. No pics of spacer, but you can experiment with different size washers and may have to file it down a bit to fit. Mine is just steel, but you can use brass, or copper if you can find it.

Re battery size. Overly long cells tend to cause tailcap switches to malfunction; too much pressure, and you are right, cap won't screw all the way down sometimes. Also bottom of batteries can dent in with excess pressure. Price we pay for using after market parts with SF bodies. Building up the plate in the tailcap that contacts the lip of the battery tube body is a way to reduce amount of turns you need to make contact. Like adding threads to body and ineffect lengthens volume of the body so batteries are not under stress. In your case you get an extra turn or so for good contact without pressure.

Bill

Bill
 
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