Great mod-able bike headlight: Planet Bike 2 Watt Blaze

I recently bought a 2 watt Blaze light from Planet bike for $40 from eBay. I didn't like the beam pattern too much (too narrow, it uses something similar to a TIR instead of a reflector), and the tint (slightly purple).



It turns out the head cover is a snap in (snaps on the left and right sides of the light), and when taken part, there's easy access to the LED. The CREE XR-E is mounted to a rounded rectangular 16mm x 22mm PCB, which is soldered only by two wires. This PCB is secured to the aluminum body by two small screws.



All in all, it looks like it'll be easily mod-able with another drop in PCB (20mm star should work with a bit of thermal epoxy, drilling, or other way to mount it.



If anyone's interested or has ideas, let me know! I considered dropping in a XP-G Neutral on 20mm star, but decided it wasn't enough of an improvement to spend the time and money on.



Pictures at web album: http://img16.imageshack.us/g/img0214xp.jpg/



And here's one of the six pictures:

I've been commuting in San Francisco, CA with a Blaze 2W for the last four months powering it with Sanyo Eneloop rechargeables. I dig the light, but naturally would like more lumens from it. Would an XM-L work with the same optics? I suspect not, but it would be great to go from ~100 lumens to ~250!

I've replaced the stock XR-E with an XP-G. When I get permission to upload images (presumably from an Admin), I'll post build images and beam shots. Here's a description of how to disassemble the head:

http://www.candlepowerforums.com/vb/showthread.php?315309-Q-How-to-disassemble-Planet-Bike-Blaze-%281-or-2-Watt%29-light

Can you post at a photo hosting website? I use Photobucket.

Ask and ye shall receive, sometimes: http://www.flickr.com/photos/63654603@N04/sets/72157626752906241/with/5793924695/

What I didn't mention on the flickr page is that there are two tiny `nubs' that protrude from the aluminum heatsink/body that need to be ground
off before the Indus star can mate properly with it. I used a Dremel with a Al2O3 sanding bit on it, making sure to mask off the rest of the body from the particles it produced. Additionally a very small amount of filing had to be done on the Indus star itself to make it fit where the stock LED was situated. The XR-E that I removed didn't have any heatsink grease or epoxy on it. I used a metal oxide silicone-based thermal grease to couple the LED to the heatsink, instead of epoxy. Somewhat strangely, it appears that the entire heatsink/body piece is painted, which presumably doesn't help in heat xfer from the LED. I like the resulting spot even though I suspect the optics are not optimized for the XP-G (awaits pedantic comments...).

Last night I rode about five miles across the rolling hills of San Francisco and was pleased with the result. The few times that I was in total darkness, I could rely on the light to make riding safe at 10-15 mph. Like others have mentioned about this light, at higher speeds you would probably want more light.

Total mod time from start to finish was about 1 hour. For the ~$8 LED, this was a worthwhile mod.

mdt - Has this mod held up well over time? I'm mainly concerned that ,since the XP-G board doesn't make direct contact with the metal shell of the housing, that you may experience over-heating issues. I know you used a metal oxide silicone-based thermal grease to couple the LED to the heatsink. However, since the original XR-E board was 22 mm and the XP-G board is only 20 mm, I'm wondering if the thermal grease was effective enough with a gap like that. Also, if it has worked out fine, then would something like Arctic Silver 5 thermal grease be the same kind of thing you used.

mdt said:

I've replaced the stock XR-E with an XP-G. When I get permission to upload images (presumably from an Admin), I'll post build images and beam shots.

Click to expand...

I'm pretty sure you don't upload images here. Just upload them to something like Photobucket or Flickr or what-have-you.

runun said:

mdt - Has this mod held up well over time? I'm mainly concerned that ,since the XP-G board doesn't make direct contact with the metal shell of the housing, that you may experience over-heating issues. I know you used a metal oxide silicone-based thermal grease to couple the LED to the heatsink. However, since the original XR-E board was 22 mm and the XP-G board is only 20 mm, I'm wondering if the thermal grease was effective enough with a gap like that. Also, if it has worked out fine, then would something like Arctic Silver 5 thermal grease be the same kind of thing you used.

Click to expand...

Jeez, I'm sorry for the long delay in follow-up. Yes, it has held up just fine. I wouldn't have mounted the LED if there had been a gap b/t the back of the star and the sink. I did have to slightly modify the shape of the star, but contact was positive. I use this light daily on my commuter. It's never let me down =)