Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Electronics, Lighting, & Gadgets HRM, GPS, MP3, HID. Whether it's got an acronym or not, here's where you'll find discussions on all sorts of tools, toys and gadgets.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 07-13-13, 04:13 PM   #1
shurin
Member
Thread Starter
 
Join Date: Apr 2013
Location: Estonia
Bikes:
Posts: 37
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
My semi-DIY bike light

Out of curiosity I bought a ~13.50 cheap Chinese 3-mode flashlight with CREE XR-E Q3 LED (claimed 120 lm). I found it quite bright, but runtime of ~1.2 hours on 3 AAA 1000 mAh NiMH cells is not good. So I got another cheap light for ~7.50 from local supermarket, which turned out to be direct-drive (no constant current circuitry or different modes) CREE XP-E with a little higher luminous efficacy.

So I dismantled everything and built a 3-mode XP-E light of about 150 lm (calculated) output and used one tailcap, ballpoint pen, copper braiding, microphone cable, IEC power connector, two switches (on-off tumbler and on-(off) push-button for easy mode changing), low-voltage power connectors, battery holders for 3xAA batteries, cheap digicam case and various other small bits'n'pieces to hack together an external battery pack of 4...5 Ah (I've not bought the NiMH cells yet). Also made a crude shallow parabolic reflector from a piece of aluminum sheet to better harness the LED output. Around 28 total ex. cells, which will be another ~25 (for a comparison, non-rechargeable Cateye Econom Force HL-540 is around 60 without batteries (4xAA cells), is claimed 170 lm and 2 hours runtime on high setting) .

Future upgrades might be CREE XM-L2 LED and different driver for ~900 lm output at high and ~400 lm at medium settings - but heatsinking might become a problem, even XP-E at around 600 mA warms the flashlight body up pretty well, XM-L2 at 3 A would need a whole new body. Maybe Li-Ion cells for battery, plus a suitable charger (the latter are notoriously hard to find and cost an arm and leg where I live, that's why I opted for NiMH for now).



Attached Images
File Type: jpg IMG1769.jpg (101.6 KB, 10 views)
File Type: jpg IMG1761.jpg (103.3 KB, 22 views)
File Type: jpg IMG1762.jpg (99.3 KB, 22 views)
File Type: jpg IMG1764.jpg (94.7 KB, 21 views)
File Type: jpg IMG1765.jpg (104.0 KB, 19 views)
File Type: jpg IMG1766.jpg (101.7 KB, 15 views)
File Type: jpg IMG1767.jpg (101.4 KB, 14 views)
File Type: jpg IMG1768.jpg (100.3 KB, 13 views)
shurin is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 12:24 AM.