Why can't manufacturers cut a clean thread?

Not naming names, but most of my recent purchases appear to have pretty poor threads for either the tailcap or lenses

I'm expecting high quality perfect threads for the sort of money these lights cost. It's not the anodising either, as I'm used to working with RC cars (Tamiya etc) and their threads are beautiful.

What's going on?

I'm quite disappointed purely from an engineering / aesthetic / enjoyment point of view

Also what's with the lack of instructions? Most of these lights have different settings / battery combinations, yet you get nothing?

I was going to say ... cost and QC but it sounds like these were not inexpensive lights. I've had pretty good luck with most of my lights, some better than others for sure (my Jil is like silk compared to my Lumapower or Liteflux) but thankfully none have been awful. I'd be disappointed if I bought a Surefire, Novatac, Peak, etc... and they had sloppy threads. OK - real disappointed.

I wonder this also.
I also find 90% of light have threads that are WAY to fine.
Surefire threads are dead on.Deree is nice also

name the model please, i would like to hear more about this problem.

Well, I wasn't too happy with the (tail) thread on my Lumapower Hunter M3 then I received my Tiablo A8Q5 which has worse (tail in particular) threads. - a lot of slop. My Inova's and Fenix are pretty good in comparison.

They are not mis-manufactured (as in I need to send them back), but just too sloppy in my opinion, as if the machines used to lathe the threads are old (or too inaccurate). When done up tight there is not a problem, but the usage of the threads is not enjoyable.

By the way, I'm very experienced mechanically, so this isn't me not understanding threads.

(p.s. batteryjunction links for reference of the lights only)

I am not so impressed by the threads on my Fenix L1D CE, they are too fine and sloppy. It isn't that bad but I would expect something better from Fenix.
The threads on my SF A2 are excellent, very smooth and no chance for cross-threading due to the dimensions of the threads.

I hear ya. Theres nothing more aggravating than getting a new light and it has gritty dirty threads. :hairpull:

From the lower end lights that I have got, the nuwai threads are very smooth and well machined. Some manufacturers need to put more thought and quality control in the machining/threads dept.

All of the threads on my SF's have been flawless. Same for my McGizmo goodness.. :thumbsup:

The threads on my latest light, a ROV 3W (re-branded Nuwai), are really good. While they came dry, they were still smooth as glass on both ends with no grittiness whatsoever, which is pleasantly surprising.. :twothumbs

My guess is that the threads on mass production lights are cut at a higher speed than is optimal :thumbsdow

That would be my guess as well...Speed, quality and cleanliness of cutting oil and quality of the stock material are all factors.

Aren't most of these threads rolled on the smaller lights?It looks like it to me.
DON

Own and have handled many lights........seems you really do get what you pay for. McGizmo, TnC, Endeavor (CR2 Ion), Data (Spy) and Surefire lights, have threads, switches, anodizing etc, that are quality and noticeable,

TnC (Chris O) does an extremely nice job with bodies and threads and when you use, hold and see, you can really see and feel the difference.
The McGizmo Alpehs and Surefire in the bottom picture are prime examples, the first two are TnC.

Nicest threads I've seen is the old Longbows

My guess is that it is a cost cutting measure. They keep the tolerances a little loose to minimize the reject rate and possibly stretch the cutting insert life a little. Most of these are likely CNC machined as opposed to any other method. I doubt that anyone is rolling threads in aluminum.

If you've ever cut threads before in the lathe, you'll notice that the difference in size of a nice fitting thread isn't much different than a loose fitting thread. It is really easy to get the thread a little too large (internal threads) or a little too small (external threads) and they feel really loose. I'd say that from a mechanical strength standpoint they would probably be little difference in the threads.

Surefire uses a chromium conversion coating on their threads (at least on the one Surefire I own). That provides some lubricity. HDS and NovaTac anodize their threads. My Huntlight has pretty loose/sloppy threads, but they function fine. They are all cut cleanly, no raggedy threads, just some are sloppier than others.

I haven't seen a single light with anything other than perfect threads on my Surefires, HDSs, Arcs, and McGizmo lights.

you get what you paid for.

I don't know about their newest offerings, but I have to say that my original Jetbeam Jet-1 Mk2 had VERY smooth threads. Although a bit fine, They were very nice. After a little cleaning and lube, it is one of the smoothest tailcaps I own. Overall I've been very impressed with my Jetbeam lights (minus their new UI system, ugh)

SureFire lights have good clean smooth threads, unlike my cheaper G&P light bodies... eh, YGWYPF I suppose these days :shrug:

yet I still hear people make claims like "DEALEXTREME" lights ARE SUREFIRE QUALITY.

SF threads are not too fine, cut quite well, and have this night coating that reduces galling.

My best threads would probably be those on my L2D-CE and one of my DX lights (amazing quality this one!). The worst threads would be on my arcs and some other DX lights.

the best threads are on the NS Raw :thumbsup: perfect
2nd SF
Fenix arent bad

most of the others have been rubbish and ive sent a light back before because it was so bad , it cost me $150 so i expected more.
the replacement was better but still no gold star.....must try harder :sigh: