The There Are No Stupid Questions Thread

What is the impact of a reflector which is not 100% spotless?

To tweak the beam of my C8 i have sanded down the gasket until it was paper-thin, which improved the beam but it was still not a laser beam, it diverges.
So i filed down the reflector quite a bit, i dont have the guts to go any further at the moment.
Filing and sanding caused a dirty reflector. I have messed up 1 reflector earlier and now i know it is a p.i.t.a. to get it clean.

Got it quite clean with soap, running water and a hairdryer :wink: but it still shows minor stains due to dried water, which annoys me, do i have to, other then cosmetics?

I believe you mean, “How is babby formed?”.

And its corollary question, “How girl get pragnent?”.

The influence of some dust specs can not even be measured, but stains really do influence the throw somewhat, but nothing that can be seen by eye.

About beam divergence: a led in a reflector can not be seen as a point source, led dies have a certain size, the hotspot of the beam is in fact a (twisted) image of the led die. With the led as source, the reflector as optic, and the hotspot as image, the normal lens formula sort of applies in which the distance from optic-to-hotspot divided by the distance from led-to-optic determines the magnification of the led die, the size of the hotspot.

In short: because a led is not a point source, the beam in even a perfect reflector will always diverge.

Mostly , in the old fashioned way...

Thank you Jos, very helpful!

I’ve had pretty good luck before rinsing a reflector with distilled water and using a can a air to help blow out the particles, then rinse with isopropyl (rubbing) alcohol and blow it out again with the air. Using distilled water and the alcohol didn’t leave water mineral marks.

Thank you Robert, i was thinking the same, have to buy some compressed air, or even better a compressor :wink:

why dont make 3V version xhp70.2 :frowning:

I’ve read there often is some oil in compressed air which is not good for reflectors. I use this tool with good success:

One possible reason: lower voltage (all LEDs parallel) means higher current for same output which results in more resistance losses in cables, contacts, PCB traces et al.

Thanks Flashy Mike, just ordered one from BG, will try out soon!

okay, then Why CFT-90 not running on 12V led :stuck_out_tongue:

I havn’t found oil in the can of compressed air, but definitely use a dual air drying system on my air compressors when shooting lacquer

I’m going on a long bicycle tour and would like to take 2 18650 lights (Lumintop Prince and Nitecore HC30).
Is there a small portable charging device that I could use on my trip that I could charge and carry with me to charge up my batteries along the way?

Yes, there are several options for that. But there is one portable device clearly the most efficient, cheap and compact, it is called ‘spare batteries’ :slight_smile:

Depending on how long the trip is, there comes a point where it becomes more efficient to bring a charger rather than a mountain of batteries. :-)

Thanks for all tips guys, managed to get it quite clean.

I have filed down the reflector even more and now the bottom is really thin, just as the gasket, i think this is all i can get out of it, very happy.

To clean it i have rinsed it using running tap water and blew it out using my new dust blower which recently arrived. After that i used 70% rubbing alcohol which i still had lying around (kids…) and used cotton wool which worked great.
Blew it out once again and it ended up really well!

XPL-HI V3-1A with BLF X6 driver

I have got the Xtar Ant MC1 Plus, which is really small and useful, i just use my phone’s charger

Maybe this?

magchgr by F/8, on Flickr

solarchgr by F/8, on Flickr

I have a big 32650 waiting to be used on the flashlight. Anyone recommend me a light ? Thanks.