CR123 body stuck on Fenix L1T head

I received a brand new CR123 body just yesterday. After screwing it on to the head about two-thirds of the way, it started to become hard to turn. Before that it was smooth as silk, so I'm reasonably certain it's not an issue of cross-threading. Thinking that there might be some machining debris in the threads, I started to unscrew it and shortly thereafter it seized solid. I'm now unable to turn it in either direction even a slight amount.

Has anyone had a similar experiece? If so, were you able to get the two pieces apart again?

Thanks,

Fred

Welcome fredb! I'd contact Fenix Store if that's where you bought it and let him
know about it. He's a great dealer and will take care of you. I haven't had this
experience myself.

fredb said:

I received a brand new CR123 body just yesterday. After screwing it on to the head about two-thirds of the way, it started to become hard to turn. Before that it was smooth as silk, so I'm reasonably certain it's not an issue of cross-threading. Thinking that there might be some machining debris in the threads, I started to unscrew it and shortly thereafter it seized solid. I'm now unable to turn it in either direction even a slight amount.

Has anyone had a similar experiece? If so, were you able to get the two pieces apart again?

Thanks,

Fred

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YES!! I have an L1T and an L2T. I bought two 123 bodies. I replaced the L1 body with the new 123. It works perfect. However, when I tried replacing the L2 body with the other 123, the head from the L2 light will NOT thread onto the 123 body. It goes about a turn and a half and locks up! Tight! It won't go any further.

The head from the L1 will thread onto either of the new123's. No problem.
Both heads will thread onto the stock single AA or the two AA body. No problems.
It's just that the one head off the stock L2T will NOT thread onto the either of the new 123's.

How can this be? Does anyone have any ideas? :thinking:

The best thing I know for getting things unstuck is WD-40...

Just have to be careful how you apply it though!

Once you gall the threads on aluminum you are pretty much done. With my unfortunate experience, after the galling occurs it's down to destruction. WD-40 works on dirty/rusty steel, not galled aluminum. Galling is when two metal surfaces basically fuse together. Good luck. Maybe a machinist can speak up with some advice. Maybe a quick pass or two with a torch may expand the outside threads enough to give you some give. Take all precations with open flames if you decide to try this method. Maybe even the light in a freezer zip lock bag in boiling water may help. Remember though, some things inside are plastic and don't take to heat like the body so short exposure time to heat.

machinist here.

if they got stuck finger tight, they will come lose with just a bit more pressure. I would try wraping the body and head in masking tape, then using a 3 jaw chuck(on the lathe, no power) and a strap wrench.

once you have the two seperated, chase the threads with a single point tool.

if the threads are bare aluminum, I would use a dry lube, like graphite, or teflon/moly.

my $.02

this has happend to me a LOT. The most memorable expierence i had with this was with an ORB. I got it, it siezed up within a few weeks, than i sent it in. Within a few days of recieving it, they got jammed up again! I kept it sitting for about a year, it still woudlnt come out.

I EVENTUALLY got it undone by soaking the tailcap in WD-40 AND by sticking screwdrivers in the lanyard hole, and turning with a LOT of force. One of the screwdrivers snapped.

After i got it working, i traced along the threads with a razorblade, and took off quite a bit of "Messed up thread". It was finally smooth, but it was pretty beat up, and it still had a flickering problem, along with a foggy window.

Also happend to my QIII, where i drew blood trying to unscrew it, without the tailcap moving at all. Later on, i the QIII body was SHEARED by the force used trying to remove the tailcap. I dont think the cap moved at all!

It is a very serious problem.

Thanks everyone for your words of wisdom! Fortunately the supplier said he'd make everything right. Now I just have to be patient and wait, which really is the worst part of this whole ordeal.

Would lubing the threads before putting them together help keep this from happening?

I have similar problems with 123 body and L2T head. I thought that the body was damaged in the mail and not completely round... It is not competely stuck, but very hard to turn.

LifeNRA said:

Would lubing the threads before putting them together help keep this from happening?

Click to expand...

I had the same thought as well. I'm thinking that when I receive the head and body back that I'll use graphite powder on the threads to help prevent them from seizing again. I understand that there might be a bit of abbrasion to the o-ring by using a powdered lube, but removing and replacing an o-ring is far easier than separating the solid metal blob that I have right now.

One tool which might help with this is a jar opener called a "Strong Boy" made by Zyluss. Get it in a kitchen shop.

It is like a lightweight strap wrench, but also has a rubber gripper to help with small things.


They are popular in the film industry for removing stuck delicate things like camera viewfinders or small filters etc.

I've had mine for a week or so with no threading problems and just today installed the o-rings because I had to wait until I got some silicon grease.

After reading this thread I unscrewed the light from the body, cleaned off any silicone from the threads, applied some graphite, and now it's not as smooth as before when twisting from high to low and back. I don't recommend the graphite. It now feels like it's grinding right at the last turn before it's screwed in completely.

Now I'm going to clean out the graphite and put some silicone back on.

Followup:

Well, here's why it's not turning smoothly anymore. Starting 5 turns down you can see the threads start messing up. I hope it's not the new CR123 body doing this as I love this thing. I just won't be unscrewing it any more than necessary.

Be careful with the silicone as it is non-conductive in purer forms and can cause problems with lights, especially if they use the body threads to create a circuit so I have been informed.

Is it possible that the O-ring self destructed? This could cause a jam, if the ring were dry.

Lee1959 said:

Be careful with the silicone as it is non-conductive in purer forms and can cause problems with lights, especially if they use the body threads to create a circuit so I have been informed.

Click to expand...

It's bulb grease.

arty said:

Is it possible that the O-ring self destructed? This could cause a jam, if the ring were dry.

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I'm pretty sure the o-ring isn't the culprit. It is well-lubed and the two parts are practically welded together--I don't think a fragment of rubber would put up the same kind of fight. I could be wrong, of course.

St8kout said:

I've had mine for a week or so with no threading problems and just today installed the o-rings because I had to wait until I got some silicon grease.

After reading this thread I unscrewed the light from the body, cleaned off any silicone from the threads, applied some graphite, and now it's not as smooth as before when twisting from high to low and back. I don't recommend the graphite. It now feels like it's grinding right at the last turn before it's screwed in completely.

Now I'm going to clean out the graphite and put some silicone back on.

Click to expand...

Thanks for the feedback. I've never tried graphite powder with aluminum-on-aluminum and based on what you're saying, I think I will opt for a conductive liquid lube.

I put the silicone grease back on and it's smoother, but refer to my earlier post with the pic of the now mangled threads. It still works ok, but I won't be messing with unscrewing it anymore.

Lite_me said:

It's just that the one head off the stock L2T will NOT thread onto the either of the new 123's.
How can this be? Does anyone have any ideas? :thinking:

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I just got a L2T and a 123 body in the mail today. The head fits on the body fine.

Can you swap heads between your L1T and L2T?

FWIW PB Blaster works great to unstick anything. Much better than WD40. It's vey possible it could destroy the innards of your light though.

My L1T head was rather difficult to thread onto the 123 body but the L2P head went on smooth as silk.

To check for burrs on the 3rd party body, grasp the threads between your thumb and forefinger and twist the body slowly. You will feel any burrs. If there are burrs present, use some 220 to 400 grit sand paper. Wrap a small piece around the threads, grasp with thumb and forefinger and spin the body (not yours, the flashlight body) three or fours times. Not a lot of pressure needed. Then blow off the threads with canned air or wipe clean with a paper towel. That will help smooth out the installation.

Of course its too late now, but for the next time.