Mountain Bike Reviews Forum banner
1 - 20 of 158 Posts

·
Registered
Joined
·
532 Posts
Discussion Starter · #1 · (Edited)
While I have a good set of lights ( Wilma 6, Edison 5, and a Dinotte 200L) I was interested in the DIY approach many on this board have pioneered.

Design criteria:
1. I'm going to use this light on my helmet so I don't want hot spots and the beam must be wide and uniform. Will use in parallel with a bar mounted light so I don't want to see a bright spot dancing in and out.
2. Easy contruction - no milling or machining. Keep metal part count to a minimum. Only simple hand tools required.
3. Simple assembly.
4. Maximum heat transfer to ambient. Will be running at 1000ma.

I haven't finished it yet. Still need a connector for the power in and to try it out with the 2600mah Li-Ion battery I bought and of course mounting. Not too worried about that part. The beam shot is with an 8 AA NiMH pack so I expect this is not the brightest beam I will end up with.

Parts:
Aluminum pieces
case - 50mm wide with 1.5mm wall thickness cut to 1.7 inches in length
L-bracket - 1/8" thick
back cover plate - 1/16" thick
Front cover - Polycarbonate - .093 thick (wish I could find a thinner piece)
driver - 3021-D-E-1000 Buckpuck
optics
- CRS-D +/- 7 degree
- CRS-M +/-14 degree
LED - 2 Cree XR-E WC tint Q5 mounted on the MCPCB star

assorted screws, thermal adhesive, glues, wires, etc.




I think I achieved my design objectives. The construction was very easy especially once I found the perfect fit case material. The inside width and length perfectly fit the optics with 1mm gap on each side. The use of the L-bracket serves to mount and position the leds just right while maximizing contact with the top of the case. Only required two screws to hold the assembly in place. I have approximately 2 square inches of surface contact between the inside case and the top of the L-bracket. The case gets hot fairly quickly but even after 10 minutes on high it is not too hot to hold in your hand. The beam is excellent. I'm most pleased with that part. The first pic is of my DIY at 1000ma using 2 9degree optics. Those Q5s are VERY bright. The second pic is my Wilma on high for reference. The Wilma is only slightly brighter in the center. Aperature 4.0 and shutter was set at 1 second.

Thanks to all those that posted earlier DIY projects. Your efforts are inspiring.
 

Attachments

·
Registered
Joined
·
532 Posts
Discussion Starter · #3 ·
Glad you like the design...


I'll use a lite amount of glue to hold the polycarbonate face plate in place as I don't expect to be removing it. The rear will be attached with 4 small machine screws.
 

·
Registered
Joined
·
532 Posts
Discussion Starter · #5 ·
Thanks

I got the aluminum rectangular stock here:

http://metricmetal.com/products/square.htm?gclid=CImW047GvI8CFRdPagodUB0GUQ

Unfortunately, they have a minimum order requirement. I had to purchase 5 feet of this stuff at a cost of $95 dollars. 5 feet should translate conservatively into at least 25 housings. That's fine as I have friends that want me to build lights for them. I doubt I will need all 5 feet though. Want some?

The L-bracket, polycarbonate, and back plate are readily available from just about any hardware store. Get a good file and some sandpaper to fine tune the fit after rough cutting the material.
 

·
Registered
Joined
·
532 Posts
Discussion Starter · #7 ·
more pics

Pulled out the arsenal last night and took some more pics.

The first pic is the Edison 5. Noticeably brighter than the Wilma but with the jagged beam edge
Second one is the Dinotte 200L with spot beam
Third pic is the DIY but this time with 2 25degree optics on board. Really lights up a wide swath of yard.
the last shot is the Fenix L2D Premium100 flashlight

All pics taken with an aperature value of 4.0 and a shutter speed of 1 sec.

Not sure yet which optics combo will be the best for helmet use. I'll have to try them all.
 

Attachments

·
Registered
Joined
·
9 Posts
il2mb said:
I got the aluminum rectangular stock here:

http://metricmetal.com/products/square.htm?gclid=CImW047GvI8CFRdPagodUB0GUQ

Unfortunately, they have a minimum order requirement. I had to purchase 5 feet of this stuff at a cost of $95 dollars. 5 feet should translate conservatively into at least 25 housings. That's fine as I have friends that want me to build lights for them. I doubt I will need all 5 feet though. Want some?

The L-bracket, polycarbonate, and back plate are readily available from just about any hardware store. Get a good file and some sandpaper to fine tune the fit after rough cutting the material.
Thanks for the info and the offer! I'd like to copy your design in a 3 LED version. How did you connect the back plate to the housing?
 

·
Registered
Joined
·
61 Posts
PhxCycler said:
Thanks for the info and the offer! I'd like to copy your design in a 3 LED version. How did you connect the back plate to the housing?
I've been planning to do a 3-led version (great minds and all that) as a variant on Achesalot's excellent design, and while I too originally thought of using an angle, my final choice is to use another piece of rectangular tubing, slicing off the top surface to create a channel. That way I get both a led mounting surface and a back wall in one. I tried to find pre-formed channel stock to avoid doing that cut, but without success. I haven't decided whether I'll make it with my jeweller's saw, or my circle saw.

The channel will slide into the housing the way a drawer slides into a chest, the rear surface forming the back wall. If I had access to precision metalworking tools, I'd cut lips and channels for o-ring sealing, but since I don't I reckon to recess the back wall by 0.25 inch and run a bead of silicone caulk to take care of it. With a well-polished mating surface (the bottom of the channel), some thermal grease, and bolts to clamp them together, I should think the thermal transfer will be very good. The only thing I (slightly) regret is that the 3x1 tubing from online metals has a 0.125 wall.
 

·
Registered
Joined
·
532 Posts
Discussion Starter · #11 · (Edited)
Katz,

I was also looking at a 3 led design originally but that was back when I had the Cree Q2. With the Q5 and higher bins becoming available I'm beginning to think 2 leds get the job done. The Q5s in my light supposedly put out 235 lumens each at max current. The Cree R2 now available should be in the 250 lumen range. This is the main reason I bought the Wilma and not the Betty. 7 leds, in my mind, is not upgradable. 1400 lumens to what - 2000! Sure Lupine will offer an upgrade at some point but I don't need that much light. I think the next upgrade Lupine offers for the Wilma will take its output comfortable over 1000 lumens. Bike light designs will peak at around 1000 lumens and from there the direction in the market will entirely emphasize lighter and smaller heads with smaller batteries and loonger run times. Ever increasing light outputs have to peak at some point. Also remember that fewer leds makes for a simpler design.

I'm quite surprised how the beam on my DIY looks. Very similiar in shape and uniformity as the Wilma. The intensity is slightly less but the Wilma cost me $600! As led output increases eventually we will only be buidling DIY with a single device. Wow! imagine a single led running at 600 lumens.

Good luck with your build
 

·
Registered
Joined
·
61 Posts
il2mb said:
Good luck with your build
Thanks for the good wishes. It was great seeing the results of your build - it was like seeing a preview of my own, only narrower.

The success of your build also convinced me to use the square optics - they really do a good-looking job. And with the amount of light you're getting out of 2 leds, I think I'll be able to do a successful "lo-beam" by turning off my spot altogether and cutting the power on the floods to the bone. And with all three cranked up, plus big arrays of amber leds flashing maniacally, I hope even the drivers talking on their cellphones will get scared and think Godzilla is bearing down on them. :D
 

·
Registered
Joined
·
577 Posts
That's a good looking design. Really simple and solid. Maybe I should do 3 2xSSCs instead of 2 3xSSCs. Hmmm.
It is really comparable to those commercial lights. Great job.
What kind of thermal adhesive did you use for the L bracket? Is it in there for good, or can you remove it?
BTW - How cheap is cheap?
 

·
Registered
Joined
·
532 Posts
Discussion Starter · #15 ·
thanks

02Slayer said:
That's a good looking design. Really simple and solid. Maybe I should do 3 2xSSCs instead of 2 3xSSCs. Hmmm.
It is really comparable to those commercial lights. Great job.
What kind of thermal adhesive did you use for the L bracket? Is it in there for good, or can you remove it?
BTW - How cheap is cheap?
It really is a simple design. Now that I've built this one I'm going to build two more for the bars. However, I will connect them to a single power supply. Two Q5s on full is really a lot of light. Going with a 2 led light head is simpler build than a 3 led head. One of these on the bars and one on the helmet is plenty of light. But for really technical trails I have the option to add the second bar light and frankly there is space to do it so why not.

I use Arctic thermal paste (NOT adhesive) between the L-bracket and the case. Yes, that is removeable.

Cheap? Optics, driver, LEDs cost about $50. I bought a 2600Mah Li-Ion battery with charger for about $100 but you can use 8 NiMH AAs for a lot cheaper. (I can also plug in a 9 volt transistor battery for backup - can't do that with a 3 led head.) For your first light build more expense is incurred due to the need to buy wiring, solder, adhesives, glues, and all those things that when you buy them you have to buy enough for 20 lights because that is just how things are sold. For example I bought a tube of Arctic thermal paste. It wasn't cheap but I only needed a little dab. If I go on to build 10 more lights I'll end up using it and getting my money worth. I also had to buy 5 feet of the case material for $95 and I doubt I'll use all that up. In addition, this doesn't take into consideration any tools that you might have to purchase. So the title of this thread should have been "DIY - done easy" rather than done cheap. it only gets cheap after building 10 or more lights. If I take those economics into the calculations I think this design could be put together for about $150.00 - $175.00 using a good Li-Ion battery
 

·
Registered
Joined
·
577 Posts
Yes, I am finding those hidden costs too. But hey, new tools are pretty fun, so what the hell. I'm in it for about $200 at this point, but I've got the stuff for 3 or 4 lights. (3 Cree Q5s and 6 SSC P4s). The Aluminum tube I bought at wholesale via metal supply warehouse scrap pile/shop set me back only $22, along with a nice 1/4 inch (7 mm) Al slab to use for heatsink. I have some square tubing from work for free, but I saw some rectangular tubing at the metal supplier just like yours and I thought it would work too. You proved it works, and looks good doing it. Wish me luck!!
 

·
Registered
Joined
·
914 Posts
where are you guys getting these square optics? I have alot of 20mm round ones but i can't seem to find the square ones where i can buy them. I really like how yours looks and am currently building a helmet light. I have built 3 lights already that mount on the bars that use 6 led's and its alot of light. But i am looking into a smaller 3-4 led setup for the helmet and am trying to make it as small as possible and simple. I bought a 35mm round lens that holds 3 led's that i might use or go with a design like yours. I also already bought a shark controller (boost) so I can use a pot.

I have narrowed it down to either 3 led's in the 35mm lens, 2-3-4 led's in 1" round tubing with round lenses (which will be harder to work with) or 2-3-4 led's in 1" square tubing (but can't find square lenses yet). I think the square tubing would be the easiest to work. Just waiting for all the supplies to come in so i can start working on it.

But i really like your design. Good work.
 

·
Registered
Joined
·
1,281 Posts
Another option for batteries (if you can source a base) is your standard Li-Ion camcorder battery. I'm using a Sony InfoLithium M style base, and can get anywhere from a 1000mAh pack up to a 5000mAh pack for them. If you happen to own a camcorder, you can do the same thing and not have to buy new batteries. I got a broken camcorder and pulled the base off it for my DIY.
 
1 - 20 of 158 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top