Opening heads with heat

Fallingwater

Flashlight Enthusiast
Joined
Jul 11, 2005
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Location
Trieste, Italy
Some manufacturers (I'm looking at you, Fenix) put threadlock everywhere, making heads exceptionally hard to disassemble. For example, I have an old Fenix L1S that I've been wanting to convert to SSC since forever, but I can't because the head is stuck solid.

Now, I know some people boil the head in a plastic bag to soften the threadlock, but I don't happen to have suitable bags, and neither I know where I could get any around here.

I do have a propane torch, however. Considering I really don't care if the Luxeon LED inside the L1S gets damaged by heat, do I run any risk of ruining the rest of the head if I just put it lens-down on a suitable surface and blast away at the sides?
 
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I think that some use a hair dryer on highest setting, moving it around. Boiling water is not too much above 200 degrees, so maybe should be very careful if you use a propane torch, or maybe not at all.

Bill
 
I'm not familiar with the L1S, but the Quarks are assembled with thread lock too, and the Quark Turbos are the biggest pain to crack open. What I do is take an old leather belt and cut two pieces from it, roughly 2 1/2 inches long, then I thread the body into the head to keep from warping the head where the body threads in (if the light has a clip that's close to the head, and if it's removable, it would be best to remove it; I damaged a clip once doing this), get two pairs of Channel locks, then insert one cut piece of belt into the jaws of each one, but put it in so that the leather covers both the top and bottom jaws.

I do the same with the other pair, and proceed to grip each side of the head. Then, while using some profanity and gritting my teeth, all while being careful not to let the jaws touch the anodizing, I make sure the teeth aren't cutting through the leather. Finally, after using a few more choice words, and my knuckles crack a couple of times, I give it one more shot and bam! the head breaks loose:D. I'm not sure if this helps you any, or if the L1S head can even be disassembled like this, but it's an idea I guess. Good luck either way.
 
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Good lord ti-force! :sick2: I'm going to hire you the next time I need someone to get the oil filter off my car which the gorillas at the factory tightened so tight you can't budge it. LOL

I've cracked a few heads lately and some are easier than others - but pateience does pay off. Initially I thought only some heads would crack but then I realized it's just how much glue they put in them.

The boiling method has worked very well for me - and I just use a plain ziplock - but don't boil anything you would want to risk getting wet. And sometimes the first boil doesn't work and it takes 2 or 3 dips.

Other heads (Nitecore, SF and a few others) whic I wouldn't want to risk getting wet I have cracked with a small Radio Shack butane torch - its the small red one that comes with the soldering iron head. Just keep moving it around and heat the seam and threads of the head evenly and you should be fine. As with the boiling though, it may take a few times.
 
Good lord ti-force! :sick2: I'm going to hire you the next time I need someone to get the oil filter off my car which the gorillas at the factory tightened so tight you can't budge it. LOL
:crackup:




I might ride over to my local Radio Shack to purchase one of the torches your talking about. What's the old saying? Work smarter, not harder:D. I do have some questions for you though.

Have you noticed any discoloration in the anodizing after using the torch?

How do you know when the head has been heated enough?

What do you use to unscrew the two halves once it's heated enough?
 
To make a L1P with P4 I had to sacrifice one of them. In other words, I used two L1Ps to make one with the SSC P4.

I have some custom made leather strap wrenches to open flashlights bezels. Usually, opening the bezel requires the application of some form of heat. A propane torch may be ok, but I prefer a more appropriate temperature controlled heatgun.

In any case, the reflector of the L1P distorts and gets opaque even with application of small quantity of heat to the bezel. It is made of aluminium, but the reflective finish is plastic. The SF and Mc-R reflectors I was used to, are electroformed and/or vacuum coated, and impervious to some excess heat.

In the L1P, the aluminium on the outside is too thin to withstand the excessive mechanical strenght that would be required without the application of heat to soften the threadlock.

Therefore, I opened with heat one L1P head, destroying the reflector. I opened another L1P head with a saw, and saving the reflector.

I don't buy Fenix for modding anymore, but I buy some nonetheless; I keep a special eyes on moddable lights, like the Olight M20 or the Nitecores and Jetbeams.

I believe the use of threadlock, from the manufacturer point of view, improves the management of the warranties; on the side of the normal user - it avoids that the lights may disassemble by themselves.

From the point of view of a modder, excessive threadlock can be a nightmare.
It is my opinion that use of threadlock should avoid a casual self-disassembly of any given light, but it shouldn't be of impedement to its maintenance. For a modder, a moddable light is a long lived light...
For the chronicles, the worst case of all times of too strong threadlock has been the Arc4, followed from the SF U2.
Fenix doesn' t use potting epoxy like in the Arc4 or red loktite like in the U2, but the combination of thin walls and cheap reflector had a similar disruptive effect.

May be CPF hobby modders should push manufacturers to indicate in their ads if the light is threadlocked or not, and if it is user-maintenable....

Regards

Anthony
 
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:crackup:




I might ride over to my local Radio Shack to purchase one of the torches your talking about. What's the old saying? Work smarter, not harder:D. I do have some questions for you though.

Have you noticed any discoloration in the anodizing after using the torch?

How do you know when the head has been heated enough?

What do you use to unscrew the two halves once it's heated enough?

- No discoloration - but I don't hold it steady and make sure to keep moving the heat around.

- You keep trying to give the head a turn very minute or so.

- See ti-force's post, his method is spot-on, except I have used big thick rubber bands rather than a leather belt.
 
The temp you need to hit to weaken the thread locker depends on which thread locker compound is used. See this, for example.
 
I would like to offer another alternative for heating the heads to get them open. A cheap mug warmer. Look at the second picture down in this mod thread for a good view.

I also use the mug warmer to heat LEDs prior to reflow soldering them to MCPCBs. 10 or 15 minutes is enough to ensure that the moisture is driven out, and that the LED won't suffer thermal shock.
 
Hi DatiLED,

at the time of your post on modding a L0P, I found relatively easy to mod it with a P4 LED. The bezel opened with great ease compared to L1P, without any damage to the reflector caused from heat.
By chance, do you have any idea how to crack open a Peak Pacific? It looks fully potted.

Regards

Anthony
 
Hi DatiLED,

at the time of your post on modding a L0P, I found relatively easy to mod it with a P4 LED. The bezel opened with great ease compared to L1P, without any damage to the reflector caused from heat.
By chance, do you have any idea how to crack open a Peak Pacific? It looks fully potted.

Regards

Anthony

Check this out.
 
I do have a propane torch, however. Considering I really don't care if the Luxeon LED inside the L1S gets damaged by heat, do I run any risk of ruining the rest of the head if I just put it lens-down on a suitable surface and blast away at the sides?

I have a propane torch. Yes, there can be "too much heat" applied. But from 2 or 3 heads I've opened using the torch, I only really scorched one (an Arc4 that was a BEAR to losen - ended up destroying the poor thing in the process).
 
Is the L1S constructed like the L1P? That is, the pill goes into the back of the head. Or does the head shell separate?
 
You don't need a ziplock bag to hold boiling water...just boil water in a container in the microwave or stove top for that matter and stick the flashlight head in.
 
When I was unlocking older lights, I used a custom-cut piece of wood clamped in my vice, and a pair of filed down needlenose pliers on the ring. I'd put the light in a bit of rubber to keep from marring the surface while clamping in the wood.
 
Good tips guys. Thanks.

Couple questions:

Has anybody successfully gotten into the iTp A2, MiNi AA, Maratac AA lights yet?

When using a torch, are the O rings melted or damaged?
 
The L1S's head does not come apart in two parts, the pill is just screwed in from the back, so I can't use wrenches.
I'm sure if I could somehow grip the board with enough strength I could force it out, but it only has two tiny holes and everything I tried to poke in them gave in before the threadlock did.
Now I know I can't open it with heat (oh by the way, I do have a heat gun. I forgot about it in my first post. :p ) lest I destroy the reflector, so I'm pretty much stuck. *sigh*

I even considered sacrificing the driver by putting two bigger holes in it through which to poke pliers, but any replacement driver I could fit in its place wouldn't know what to do with Fenix's cool twist-head-for-modes thing.
 
I have a very faint memory of this method; come to think of it, I think you already linked it to me once when I was fighting the same problem, but I completely forgot about it. Thanks (again!), I'll try that. :)
 
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