Taking apart a recalcitrant 3 D cell Maglite

TD-Horne

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I'm having a hell of a time getting the rear cap off of a 3 D Cell Maglite flashlight so it may have had an alkaleak disaster. I was going to apply 2 large channel lock pliers to it and find out if it is salvable. I decided to ask if there are strap wrenches or another wrench type that could do the twisting without the likelihood of marring the tube? Does the gaffers tape wrap thing actually work for this purpose or does anyone know of another suitable approach.

Tom Horne
 

ampdude

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Strap wrench would be my choice. But there might not be enough surface area on that small tailcap. Or some leather gloves is most likely what I would use. You could try freezing the light, and then running boiling water on the body as well to expand it. Might make it easier to get the tailcap off with doing that and some leather gloves.
 

ABTOMAT

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I typically would first gently clamp the body in a padded vise and use a strap wrench on the tailcap. Rubber strap wrenches are grippier, but the canvas ones usually have strong metal handles you can really crank on if it's He-Man time. More often than not I end up tightening a heavy duty metal band-clamp/hose clamp around the offending part with a layer of tough rubber to protect the finish. This gives a lot of purchase that a wrench or vise can bite on without damage. Depending on the severity of the corrosion it'll either come off with a firm twist, or you'll need a 3' pipe wrench and that's all she wrote.

At least in my experience, tape wraps can help add friction to a strap wrench or something, but they won't protect the light from a metal tool.

Attacking the problem from the other side is often productive. If you can disassemble the switch and pull all that stuff out the other end, you can get vinegar in there and let it soak for a couple weeks to loosen the corrosion. If that doesn't work I'd heat it up again and spray some penetrating oil in there and let it sit for another <period of time>.

Like ampdude said, heat can work. I've sometimes gotten the body good and hot with a torch and quenched the tailcap in cold water. Sometimes helps, sometimes not.
 

bykfixer

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I've had luck using WD40 or other penetrating oil recently. Give it a good soaking for a few days picking it up once a day and tapping it on a wood surface. I read that here not long ago and thought "nah, that'll never work" but it worked on two minimags so far.

After that then try the he man stuff.
 

ABTOMAT

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tapping it on a wood surface. I read that here not long ago and thought "nah, that'll never work" but it worked on two minimags so far.
This is a great suggestion. I completely forgot. Hitting the body of the light around the threads and on the end of the tailcap can break the corrosion free if it's not too bad. Anything that causes the threaded joint to flex just a little. I've gotten pretty aggressive with this but no harm done if you use soft wood. Don't hit further up on the body-- you don't want to risk a dent.

But then some days you just can't win.

corosion.jpg
 
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ABTOMAT

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@ABTOMAT, Man, that thing looks like it sat in bilge water.
Your photo got me checking my flashlights, and I just did a couple weeks ago!
It would have been mint if the batteries weren't original to the early 70s. Whole thing was completely dissolved from the inside. Only managed to save the tailcap.
 
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TD-Horne

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Strap wrench would be my choice. But there might not be enough surface area on that small tail cap. Or some leather gloves is most likely what I would use. You could try freezing the light, and then running boiling water on the body as well to expand it. Might make it easier to get the tailcap off with doing that and some leather gloves.
Leather Gloves! Why didn't I think of that. I have some of the rescue extrication gloves from when I was still an active firefighter. Those have a great gripping surface. Since the tail cap is already "Knurled" I can take the Channellock plier to it without much concern.

Tom Horne
 

ampdude

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After watching a lot of this guy's videos over the years, I'm pretty much of the opinion that ANYTHING can be restored with the right tools, knowledge, and skills. :D

 

michiganstud

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Blowtorch. That's your only option. Report back with your findings.










******Disclaimer: I am not responsible if you actually do this********
 

735

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Did a similar restoration recently on a jade 3D. Took it to work, tried all sorts of soaks to free up that tailcap but it wouldn't even budge with 6' Stilsons.

I ended up cutting it off close to the body and hammering the threaded part out. I debated machining it back to a 2 cell size and re-threading but there was just enough to hold a new tailcap so I kept it original.

Removed the switch retaining ring with 2 long seal picks and got the switch out from the top. Drilled all the way through with increasing sizes then held the barrel and drove a 1" solid steel bar against an anvil for far too long. The body was so thin in places it ended up with a tiny compression ripple. Cylinder honed it as best as it will ever be and now it enjoys continued life.

Good luck!
 

knucklegary

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To aid in stuck battery removal, which has happened to most of us, would it help beforehand applying a thin coat of silicone paste inside tubes?

Not expensive Nyogel, but the stuff used when performing brake jobs. Such as Mission brand Silicone paste (dielectric) Sold in large tubs, i use it liberally on threads and orings, and as precaution wipe the bores just in case of a disaster

Thinking of something to use as a non stick preventative. Silicone paste, or grease, might assist when catching alkaleaks in early stages, before major corrosion

Just a thought..
 
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chillinn

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The best way to help with alkalines that leak and get stuck is by compromising. If the cells are brand new, and have not been used at all, critically not even a little bit, I personally would risk leaving them loaded in the light up to a year before pulling them. But if the cells have been used even for a minute, when storing the light even overnight I would remove the cells.

Though brand new and unused alkalines have been known to leak, it is far less common than slightly used alkalines that have been left to sit.

Just don't leave cells in the light if the cells were used at all, and I suspect the problem will be mitigated away entirely.

Also, I highly recommend Acculoop C & D sized NiMH. They are awesome. Conversely, there are C & D adapters available for Eneloop AA.

This thread makes me so sad. Those poor lights. My God, ABTOMAT, could put a NSFL warning on that image. :'(
 

alpg88

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do not bother with a Vaseline too messy , just roll a tube out of wax paper, and put it inside the battery tube, so any leak will not come in contact with the metal, or use a parchment paper for baking, or thin plastic film, but none of it will save from swollen battery that fused with walls.

If you manage to get the tail cap off, then remove the switch from the front, to do that get a small alen key, or a t8 key, iirc, and loosen the screw inside the switch, than knock on it lightly to see if you can move it back just a tiny bit, so you can grab that stop ring and remove it, once the ring is out, the switch falls right out. now you can knock cells out from either end,
 

alpg88

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50/50 mix of acetone and automatic transmission fluid works a lot better than wd40.
 

knucklegary

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do not bother with a Vaseline too messy , just roll a tube out of wax paper, and put it inside the battery tube, so any leak will not come in contact with the metal, or use a parchment paper for baking, or thin plastic film, but none of it will save from swollen battery that fused with walls.

If you manage to get the tail cap off, then remove the switch from the front, to do that get a small alen key, or a t8 key, iirc, and loosen the screw inside the switch, than knock on it lightly to see if you can move it back just a tiny bit, so you can grab that stop ring and remove it, once the ring is out, the switch falls right out. now you can knock cells out from either end,
Protective roll sounds like a good idea, a plastic tube would be perfect. But like mentioned depending on how flashlight is standing, and which battery leaks, it's good-bye switch or so-long tailcap threads.
For now, the only alkaline batteries I leave loaded are in a couple ML25LT. During this time of year they're getting used often enough, so I'm keeping my eyes on them. After storms pass, in a few more weeks they'll get unloaded
 

TD-Horne

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Will using lithium primary D cells prevent all of this in lights that are standby units? By that I mean lights that you want in complete readiness for use but are not used often.

Tom Horne
 
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