LED flashlights are a special case where the emitter and driver are sometimes installed in to the head of the flashlight in such a way that the user cannot access them, nor anything in front of them such as the lens, reflector, and o-rings.
The practice seems to be by brand, generally.
Sometimes we use the word "potting" to mean the same thing, but I believe this is done to the emitter board components to make them more shock resistant (especially inductors). If the flashlight is small enough, the entire head might be potted.
To me, this is the equivalent of Supplier A welding shut the hood of my car and telling me I can only come to them for service. If Supplier B doesn't do this, I would go out of my way to buy from Supplier B.
Fortunately, some of the threadlocking brands do a relatively good job at the quality of what they put together. Even so, defects happen, for instance this case. I repeatedly see solder flux splash over the LED dome of the best of them, affecting light output. The buyer must pay return shipping and wait for a replacement, or live with the defect. In the eyes of the manufacturer, there's nothing wrong, the flashlight is working. So they are often not going to pay for your shipping.
Also, what happens when you break a lens? I've also experienced that over time the flashlight may develop a haze on the front lens from flux and silicones volatizing and condensing within the assembly, by then you're out of luck entirely.
And as we know after a few short years, emitters are 2 or 3 times a bright, and emitters dim over years of usage. I want access to changing the emitter so I can continue enjoying the flashlight that I invested in. Also, there are times some water works it's way into the head of the flashlight from a spill or splash while changing cells, turning the head past the o-ring while underwater, or a failure in water resistance.
Now I realize that potting shut the head of a flashlight is good business. It's a tamper-resistant seal that prevents warranty claims. They would love to tell me it's time to come buy a new flashlight when we're a few years down the road.
I can't ignore the fact that threadlocking adds some robustness to the light, one less thing to move around and cause problems with operation, especially in a twisty light. For casual users who want to use a flashlight and then discard it after a few years, this might be the better scenerio. I can see there would be an improvement to thermal conductivity through the threads, but I seldom see thermal epoxy being used so it probably isn't a significant reason for it's use.
In general, I understand the reasons for doing it and it's the right of the manufacturer to choose how they manufacture their flashlights. They might consider my opinion is in the minority and there is no reason to change.
Wouldn't it be nice if they found a way to meet somewhere in the middle? For instance, Nuwai used thermoplastic-ish epoxy on their flashlights, almost like hot-glue. The head was robustly assembled, but if access was needed you could put it in boiling water and unscrew the parts.
I posted another thread where I said I wasn't going to buy cool white LED's anymore. I'm now feeling the same way about brands with threadlocked heads. It's a good thing we have so many choices on the market, and maybe it keeps me from buying too many lights. :naughty:
I'll start a list of brands that do and don't threadlock. Please help me with the list based on your knowledge.
THREADLOCKED / POTTED / CRIMPED SHUT:
4Sevens
Arc
Armytek
EagleTac
Fenix
ITP
Maratec
Microfire
Peak
ShiningBeam
Sunwayman
Surefire
Zebralight
NOT THREADLOCKED:
Dereelight
Jetbeam
Liteflux
Lumapower
Lummi
M@g
NiteCore
O-Light
ThruNite
Univex
The practice seems to be by brand, generally.
Sometimes we use the word "potting" to mean the same thing, but I believe this is done to the emitter board components to make them more shock resistant (especially inductors). If the flashlight is small enough, the entire head might be potted.
To me, this is the equivalent of Supplier A welding shut the hood of my car and telling me I can only come to them for service. If Supplier B doesn't do this, I would go out of my way to buy from Supplier B.
Fortunately, some of the threadlocking brands do a relatively good job at the quality of what they put together. Even so, defects happen, for instance this case. I repeatedly see solder flux splash over the LED dome of the best of them, affecting light output. The buyer must pay return shipping and wait for a replacement, or live with the defect. In the eyes of the manufacturer, there's nothing wrong, the flashlight is working. So they are often not going to pay for your shipping.
Also, what happens when you break a lens? I've also experienced that over time the flashlight may develop a haze on the front lens from flux and silicones volatizing and condensing within the assembly, by then you're out of luck entirely.
And as we know after a few short years, emitters are 2 or 3 times a bright, and emitters dim over years of usage. I want access to changing the emitter so I can continue enjoying the flashlight that I invested in. Also, there are times some water works it's way into the head of the flashlight from a spill or splash while changing cells, turning the head past the o-ring while underwater, or a failure in water resistance.
Now I realize that potting shut the head of a flashlight is good business. It's a tamper-resistant seal that prevents warranty claims. They would love to tell me it's time to come buy a new flashlight when we're a few years down the road.
I can't ignore the fact that threadlocking adds some robustness to the light, one less thing to move around and cause problems with operation, especially in a twisty light. For casual users who want to use a flashlight and then discard it after a few years, this might be the better scenerio. I can see there would be an improvement to thermal conductivity through the threads, but I seldom see thermal epoxy being used so it probably isn't a significant reason for it's use.
In general, I understand the reasons for doing it and it's the right of the manufacturer to choose how they manufacture their flashlights. They might consider my opinion is in the minority and there is no reason to change.
Wouldn't it be nice if they found a way to meet somewhere in the middle? For instance, Nuwai used thermoplastic-ish epoxy on their flashlights, almost like hot-glue. The head was robustly assembled, but if access was needed you could put it in boiling water and unscrew the parts.
I posted another thread where I said I wasn't going to buy cool white LED's anymore. I'm now feeling the same way about brands with threadlocked heads. It's a good thing we have so many choices on the market, and maybe it keeps me from buying too many lights. :naughty:
I'll start a list of brands that do and don't threadlock. Please help me with the list based on your knowledge.
THREADLOCKED / POTTED / CRIMPED SHUT:
4Sevens
Arc
Armytek
EagleTac
Fenix
ITP
Maratec
Microfire
Peak
ShiningBeam
Sunwayman
Surefire
Zebralight
NOT THREADLOCKED:
Dereelight
Jetbeam
Liteflux
Lumapower
Lummi
M@g
NiteCore
O-Light
ThruNite
Univex
Last edited:
