Aluminium thread on SFs

recently received my order for the M6 and C3. This is my first 'new generation' SFs. Yes i'm slow . before that the only SF that i have is the original 6P.

I realised that the thread for mounting the bezel and the tail cap on the M6 and C3 are not anodize. after a few taking off and putting back (the tailcap) there is powdery feeling on the thread. Using some alcohol i did a little cleaning and applied some silicon grease. tested it out by turning it a few times clockwise and anti-clockwise and inspected the thread. Seem that the silcon grease has now turned slightly grey.

My guess is that there is so much friction in the threads that the aluminium is grinding and some of it turing to powder. I never had this problem in the orignal 6P because the threads on the tailcap and body are anodized. however for the M6 and C3 it seems that only the tailcap is anodized and the threads on the body and a gold coating.

Has anyone observed the same issue on their SFs?

Just a guess on my part since I don't own one. But, the gold coating is probably Chemkote (sp?). The silicone grease in the threads of an Arc LS will also turn a grey color like this as you twist the head on and off. I think it's normal and don't believe it's actually doing any harm to speak of. Hope that helps.

I've seen the same thing on my Z3 & E1.I don't think it's anything to worry about.

What you are seeing is normal.

um.... ok, seem that i'm too concern. however i find that it would be better if the threads are anodized like the original 6P. I'm thinking more of in the long term. the threads will start having rough edges like i see in my maglites. the quality in maglite are worse they wear off faster.

Oh boy... maybe they should follow Princeton Tec in their line of rubber threads.... just add silicon grease and you are good to go.

For $28.11 you can upgrade your C3 to the M2 SIS bezel!

Nerd,
ewwww that;s even worse, lets' keep Al with Al and plastics wif plastics

Surefire M6,
that would look nice, what's the part no. for M2 bezel?

According to one of my pdfs, that i found off pk-engineering.com. The part number is 13586.

Geoff

Yeah aluminum tends to do that too, I guess it's similar to aluminium. I think they call it spalling. The amount of powder produced seems to depend on the quality of the threads, and maybe the particular aluminum alloy.
I have one flashlight with mal-formed threads that crunches and grinds and produces lots of powder. On the other hand my Inova X5 seems to have perfect threads. No powder and a silky feel. How do they do that?

Whoops, I seem to recall that the Inova has a stainless steel head. I guess that's how they do that.

Saint Tanic, so now you got your M6, mind if I pop over some day to have a bit of "look see"?

I have an 6P and the threads on the body around the tailcap are not anodized? It's an old style one without the hex anti-roll, non-lockout tailcap (although I've upgraded to the anti-shock bezel and LOTC). In fact, one time it stopped working because of the built up dark-grey metal particles mixed with lubricant. I now make it a habit of wiping that area clean every so often.

Originally posted by Nerd:
Oh boy... maybe they should follow Princeton Tec in their line of rubber threads.... just add silicon grease and you are good to go.

Click to expand...

<font size="2" face="Verdana, Arial">Nerd,

I didn't know about those. I'm familiar with plastic PTec threads but not rubber. Which ones are they?

Brightnorm

Saint Tanic:

i believe its normal. it happens with my surefires and maglites as well the grease on my E2e has turned a dark green from the anodizing being worn off, but after i wiped off the gunk the threads were still coated with the green HA so i don't think its anything to worry about. just make sure you don't cross-thread or strip the threads when you're screwing the head or tailcap in. if it doesn't seem to catch well, back off the head/tailcap and try again.

Originally posted by eluminator:
Yeah aluminum tends to do that too, I guess it's similar to aluminium.

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<font size="2" face="Verdana, Arial">FYI, the word "aluminum" is mostly used in the USA and "aluminium" is mostly used in Europe.
They are the same metal...

Greetings,
Velcro

Soft aluminum does this, it's called galling. Thin silicone grease works as well as anything, and a good cleaning with an old toothbrush (you do change to a new one every three months, don't you) and a new dab of grease every three or four batt changes keeps it from jamming. Optical and most other precision aluminum parts are a harder alloy and are anodized which actually converts the surface to aluminum oxide (read sapphire, Mohs hardnes 9). They rarely gall unless mistreated.

Plain water and detergent is all you need to clean the threads, alchohol, acetone etc. are not solvents for silicone grease.

BTW don't try cleaning the threads with your finger tip, you may get tiny painful invisible splinters of aluminum that take days to work out.

Velcro, that was my lame and perverted attempt at humor. I guess I should use a smiley or some kind of warning next time.

Whisky, thanks for the correction. It's been 35 years since I learnt about that stuff in college and galling got transformed to spalling in the interim.

Geoffchan,

thanks!

Nerd,

Sure! will bring the M6 along when u get the 6AA batt adaptors from me. but i cant guarantee it's still as bright as a new set of batts. it drinks 123 like water.

nihraguk,

Yes! yes! I guess i will have to accept that it's normal on the SFs. However considering that the SFs have a reputation of being built like a tank with top notch quality, I wasn't expecting to see what I see on my maglites to occur on a SF. The old style 6P did not have this problem by simply anodizing the threads, in fact it feels smoother on the original 6P. From this perspective, ver 2 SFs are inferior to ver 1 SFs. Or I maybe too picky

Originally posted by brightnorm:
Nerd,

I didn't know about those. I'm familiar with plastic PTec threads but not rubber. Which ones are they?

Brightnorm

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<font size="2" face="Verdana, Arial">Oh, they are plastic? I didn't realize that, because it kinda feels rubbery... hard and soft... I am refering to the TEC 40 and the Surge. Because I am able to jam my finger nails inside.