Wavien RLT typ collar for improving beam pattern?

Flashlight Modding and DIY Parts
1

I’ve got these el cheapo UF1508’s with 72mm glass on them.

Changed the drivers and LED’s, can’t think what to now, but I can do at least 800-900 meters on the distant church spire with the one with the smaller de domed LED.

I had three of these lamps, so I took the tubes off and instead of three of them that run two cells, I now have a 1 cell, 2 cell and 3 cell.

Trouble is the beam pattern.

Guessing it is a combination of lens holder and its internal shape, the plastic insert over the LED and the internal faces of the brass pill unit itself.

Any way I was thinking some type of home made Wavien Collar type device over the top of the LED to create a neater output from the LED.

If I do not get the ‘light amplification’ of a proper RLT collar, that would not be so bad, was thinking of seeing what I can find about the workshop / local hardware stores that will be a dome of stainless steel.

Do you think this will tidy up the beam at all.?

I am also going to make a new lens holder…totally impractical for every day carry as it will be way too wide, but somethign like the 3-D design below…something also dome shaped to keep any reflections of light from the sides going out the front.

Take no notice of the LED’s in the pictures, they are the originals, now fitted with …somethg els…de domed, but pattern still like in the first pictures with the multiple rings
Comments please…

Pop a small stainless dome/ wavien collar type device over the black plastic securing ring

What size hole should I be looking at ?

All these surfaces must be what is causing the rings?

Yes this would be the new head to hold the glass…impractical I know, but to prove a point, see if it stops any reflections and reduces the rings. Can always make it smaller diameter at the lower end at a later date.

2

Maybe paint the brass pill flat black with a heater paint first?

3

Yes, already done that too when I change the LED’s and the drivers.

4

From what it sounds like to me what you want to build is more of a reduced aperture.
An imperfect RLT collar would likely cause more spill by bouncing light around at all sorts of angles.

An aperture would only need to be a disc with a hole in the centre.

I’m guessing you don’t really care about loosing light in the flood mode.

The size of the hole would have to correspond as closely as possible to the angle of light hitting the lens at full zoom.

Measure the distance from the LED to the back of the lens at full zoom and use that along with the size of the lens to determine the angle.

Then decide on how far from the led you want the aperture and size the hole accordingly.

A slightly undersized hole would probably work better than an oversized one, but will cause light loss in your beam.

I would still paint everything black as Agro mentioned to avoid any extra reflections causing more rings.

5

Well as long as it bounced the light inwards !

Yes thanks I’ll try the aperture idea, though creating a disk that I can sit at various heights……umm …how to achieve that… maybe a tube sitting over and just inside the brass pill…push fit,

have to think on that one

they are all painted black internally already , those pics were taken before I started doing any work on the lamps.

Since what I have been told about RLT collars, in my earlier post this week, is that they are merely domes with a hole in them, and do not have a special shape, so making them imperfect would be …difficult. just start off with a sphere, and a small hole, like your aperture idea, and then open up the aperture.

6

From what I understand the RLT collar to be you are correct in saying it is just a dome.

Half a sphere.

It needs to be a pretty accurate sphere to direct the light back to the LED itself. If it isn’t perfect the light would hit next to the LED and shoot out of the hole at the top at awkward angles causing more rings.

If the RLT collar is painted black inside it would do pretty much the same as just a black disc with a hole in it.

The disc does not need to be adjustable to various heights. It can be mounted at a fixed height.

A press fitted cup with a hole in should do the trick.

In photo 4 and 5 there is a nice opening to add such a disc or cup to about halfway between the emitter and where the lens should be. You can start under sized and gradually open up the hole just like you mention with the sphere.

It would just be much simpler to manufacture such a disc or cup than a sphere if recycling the light is not your goal.

7

If I can find some nice domes I’ll give it a try , no harm in having a go.

I had hoped to get rid of that glass holder in photos 4 & 5, and make another unit with a single smooth internal surface,

I’d say that recycling the wasted light is partially the goal too, I’d not want to discount doing it , if I can

I’ll see how it goes

Thanks

8

Searching in a box looking for motorbike bits …and a maglite torch reflector appears…

9

Flashlight reflectors are parabolic not spherical.

10

I have used this exact reflector in an SK68 with an XP-E2 torch and new driver. It is actually quite spherical unlike most other flashlight reflectors. I opened up the small end quite a bit and took down the outer diameter a tad to press fit the reflector into the SK68 pill. It is by no means perfectly focused and now it actually projects the image of the Noctigon board onto a wall around the beam. I left it like that since it is purely a toy and I found it amusing. That being said there is some light recycling going on because I saw a 15-20% increase in intensity. It’s been a couple years since I messed with it but I think without the reflector it was around 40kcd and with it was over 50kcd.

11

No harm in experimenting with what you have on hand.

Like Enderman says they are parabolic not spherical but it may very well give you an increase in lux as TheDude experienced, this is likely due to the shape being close enough to spherical to project a percentage of the light back to the emitter causing an increase in surface brightness.

Due to it not being truly spherical a lot of light will likeley not hit the emitter but rather around it coming back out at different angles.I’m guessing this is why there is an image of the emitter projected around the beam. Since the area around the emmiter is black this effect could be very small and not be a problem.

Chances are you could end up with a higher lux reading just with a new set of rings around the beam. This could then be eliminated by a second aperture.

This is obviously all just speculating and the only way to know is to try it.

Have fun experimenting and let us know how it turns out. Might not turn out as planned but an increase in lux is never a bad thing.

12

Making an aluminum semi-spherical reflector with a small hole as the one shown in the post is not infringing on any rights (old flashlights used reflectors with spherical curvature) and it should not be very expensive. Using that reflector upside down for personal use is also OK. Does anyone have contacts with flashlight/reflector manufacturers in China?

13

Cheap way to make a collar:
Buy one of these for $3 or $4, extremely cheap
http://www.optolife.com/diy_projector_lens/M025.html
http://www.optolife.com/diy_projector_lens/M026.html

Then get a diamond cuttion tool for a dremel or something, and use that to slowly cut the top away to form a hole.
This would be easiest on a mill, or using something to hold the dremel completely vertical.