I fixed my Peak Shasta.

[deusexaethera]

Per a suggestion in this thread: http://www.candlepowerforums.com/vb/showthread.php?t=218605&page=2

I started out with this. Note the bright (and useless) ring around the edge, and the dark spill area:

I decided to sand the LED -- but not in the "normal" way, by just roughing-up the tip so it diffused the light. Instead, I sanded the tip of the LED flat, to widen the angle of the hotspot and to shorten the LED so refracted light wouldn't be able to sneak past the edge of the reflector.

I combined one suggestion I got, to stick a bit of sandpaper on the end of a pencil eraser, with my own idea, which was to use a Dremel with a flat-tipped bit to do the sanding. The result? An eraser with a sandpaper tip, screwed onto a Dremel polishing tool. It did this:

And the beam looked like this:

Much better. But I managed to scrape up the reflector a bit, and I wanted all my lumens back (all 8 of 'em, by my estimate), so I polished the sanded LED and the reflector a bit:

Now the beam looks like this:

Not bad, I think.

 

[AFAustin]

Very nice. When you have a minute, could you post a photo of your sandpaper-on-eraser Dremel bit? Also, what did you use for polishing the LED and reflector?

Thanks.

 

[deusexaethera]

I can do that, yeah. But in case a thousand words will work too, I used a cigar punch to cut out a small circle of 900-grit automotive paint sandpaper, then used a drop of superglue to stick it to the end of a mechanical pencil eraser. Then I screwed the other end of the eraser onto the screw-tip tool used to hold polishing brushes. (I did this instead of using a flat-tipped sapphire wheel because I wanted something softer and less aggressive -- and because Home Depot closes early on Sundays.)

The part I didn't do was to fire it up and sand down the edges of the sandpaper so it would be smaller than the width of the eraser, which would've saved me the trouble of having to polish out the scratches in the reflector.

To polish the reflector, I used a bullet-tip polishing brush and Dremel polishing rouge. (Amusingly, the stuff is older than I am.) To polish the LED, I used the side of a cylindrical polishing brush, and more rouge.

 

[deusexaethera]

On a side note, my camera for some reason is showing that LED as really really blue -- it's actually the snow-white LED. (shrug)

 

[AFAustin]

Thanks for the details. Don't worry about the photos, your description is very good. One of these days, I'm going to have to spend some quality time with my Dremel and become familiar with all the wonders it can perform.

Thanks again.

 

[gunga]

Can you post any beam shots (not side views)?

I know a before shot is pretty much impossible now...

 

[deusexaethera]

First off, here's the picture of my custom-made Dremel bit. In this picture, I've already used a whetstone to bevel the edges of the sandpaper to prevent scoring the reflector -- too late, I might add:

Here's a head-on beamshot showing the spot and the spill. The flood is not visible:

And here's another beamshot showing the spot+spill and the flood. As the "dim light" guys already know, the flood is actually usable in complete darkness, despite how dim it is:

Here's a comparison shot. My old old Arc AAA is on the left, the Shasta is in the middle, and a Fenix L0D is on the right (low setting). What you can't see here is that the flood from the Shasta completely encompasses all three beams:

That is all.

 

[deusexaethera]

Bump for the people who asked questions.