Howto make a smooth reflector faceted?

[milkyspit]

I think I remember someone talking about a way to change a smooth reflector into a faceted one... or am I imagining this? I've got a light with smooth reflector that leaves several artifacts in the beam. I'd like to make the reflector faceted to smooth out the imperfections, but how? /ubbthreads/images/graemlins/confused.gif

 

[hawkhkg11]

Other than using writeright or machining your own reflector, the only way I've heard of is to clear coat the surface with Krylon acrylic gloss spray. You have to get just the right amount of spray on, or else it will get rid of the reflective properties and you will lose a significant amount of light, or in some cases I've heard that you can destroy the surface. I actually tried this today, you have to do one quick 1/2 second spray from about 2 feet. Any more, and you'll lose the "mirror surface" and it won't be reflective.

 

[lambda]

Yes, Krylon is the way to go. I've been talking this for months, and finally have some Mag reflectors to cut down and Krylon sputter to show how it works.

This requires a 10% or less humidity to effectively complete, or the coating may fog. Easy under the right conditions, but disappointing otherwise.

 

[hawkhkg11]

Lambda, could you perhaps post instructions in detail on your findings? I've tried this but am still mostly unhappy with the results. I've gotten a little bit too much of the mirror and have lost more light that I would like. I also wasn't using Krylon, but some knockoff. The exact brand name and product would help too. Thanks! /ubbthreads/images/graemlins/thumbsup.gif

 

[milkyspit]

[ QUOTE ]
lambda said:
This requires a 10% or less humidity to effectively complete, or the coating may fog. Easy under the right conditions, but disappointing otherwise.


[/ QUOTE ]

Er, how do you achieve a 10% humidity, short of taking a day trip into the desert? /ubbthreads/images/graemlins/confused.gif Around where I live, I'll be lucky even with a dehumidifier to get below 30% humidity.

 

[IsaacHayes]

Here the average humidity is around 70% on a good day. /ubbthreads/images/graemlins/icon15.gif /ubbthreads/images/graemlins/drool.gif Missouri ROCKS! I bet you can smell the steam coming off of the sarcasm. Or is that the humidity? Any beam shots with the krylon technique?

 

[milkyspit]

This might be an absurd idea, but what about taking a very small paintbrush (or even a toothpick?) and dabbing some tiny flecks of a metallic silver paint on the reflector? Or possibly even depositing little spots of solder paste on it?

Heck, maybe even depositing little spots of actual solder, or even (enthusiasts only!) strategically spot-melting tiny portions of the reflector to warp them slightly by poking gently with a soldering iron?

Or laying narrow stripes of metallic tape on the reflector?

 

[PlayboyJoeShmoe]

I doubt if I've ever even been in 10% humidity.

Dabbing, sputtering.... sounds like WORK......

Writeright! Pretty easy to use, and can make a sickly beam into something MUCH better.

Might give up a few %points in total output, but I really need to get a beamshot or three up! (Scotch Magic Tape does it too... but really hurts total output)

 

[DSpeck]

What about gently bead-blasting the inside of the reflector, then polishing it almost all the way back? Of course, this would only work on solid aluminum reflectors. If you use larger beads, it would kind of look like orange-peel, I think. Might work... /ubbthreads/images/graemlins/icon3.gif

 

[Rothrandir]

dspeck, some reflectors have coatings on them to increase reflectivity. if you polish them, you're still loosing some reflectivity /ubbthreads/images/graemlins/frown.gif

 

[lambda]

[ QUOTE ]
milkyspit said:

Er, how do you achieve a 10% humidity, short of taking a day trip into the desert? /ubbthreads/images/graemlins/confused.gif Around where I live, I'll be lucky even with a dehumidifier to get below 30% humidity.


[/ QUOTE ]

Actually, the 10% was from an old guage on the wall. A new one from upstairs says about 30%, so no, you won't have to go to the desert. /ubbthreads/images/graemlins/grin.gif

But, I've tried this days when the old guage read 35% and got real foggy results. So this is a 'dry' process.

Basically, forget anything you know about spray painting, as a nice even coat will only get you a blurry picture of the beam artifacts. You want the Krylon to just sputter onto the reflector surface in small droplets. Don't shake the can more than 15-20 sec before spraying. Spray from about 14 inches in very short burst. Rotate the reflector 90 degress between spray burst.

The one on the left is sputtered, on the right stock.

 

[Tomas]

... a tiny metalsmith with a tiny ball peen hammer?

 

[milkyspit]

[ QUOTE ]
lambda said:
Basically, forget anything you know about spray painting, as a nice even coat will only get you a blurry picture of the beam artifacts. You want the Krylon to just sputter onto the reflector surface in small droplets. Don't shake the can more than 15-20 sec before spraying. Spray from about 14 inches in very short burst. Rotate the reflector 90 degress between spray burst.


[/ QUOTE ]

Lambda, thanks for the info. Fortunately for me, I never knew anything about spray painting to begin with. /ubbthreads/images/graemlins/icon23.gif I wonder, though, how a good Krylon sputter compares with using a sheet of Writeright over the glass. Also, does the potentially high heat from the bulb (or overdriven Luxeon /ubbthreads/images/graemlins/smile.gif ) affect the Krylon?

 

[Otokoyama]

What diameter is your reflector and how thick is the existing lens? This diffusion lens may well offer a reliable cure for the artifact blues, and could easily be made in other than Mag diameters.