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Discussion Starter · #1 · (Edited)
Has anyone else modded these lights? I've recently put together a light using an old style Marwi housing and clamp and a Cree LED. I have found that it's very very cheap and fairly simple to build. It also runs extremely cool, has a long battery life off of normal AA's, and has multifunctional settings.

The reason I chose this setup is, I used to have a Marwi dual halogen setup using the same light when they first came out, but the battery and bulbs died. I loved the Marwi lights when they were working, and I used to guide my riding buddies back to the trailhead when we get caught in the dark on dusk rides. I recently got the LED bug and have been weighing my options. I'm also on a shoe string budget and couldn't afford anything retail, other than a basic commuter light.

I got the idea after seeing the success El34 has had, but I wanted to make my own heatsink and optics, because I like designing stuff and wanted to see if I could pull it off, without any help from a machine shop. All I used were spare parts from around the shop, and simple tools like a hacksaw, files, grinder, etc.

My setup is:

Old style Marwi "bell" light, with matching old style handlebar mount.

Current regulator: DX-6190 5-Mode 1-amp board

LED: Cree XR-E Q5 star

Heatsink /adapter: Scratch made from copper pipe

Optics: lens from a low power LED flashlight, and reflector from a incandescent flashlight.

Battery: 3 NIMI AA cells, In a PVC pipe and flashlight springs and caps. Velcro strapped to the top tube.

I got the light from www.hoffmanamps.com and the electronics from www.Dealextreme.com Everything got to me in a week, so I'm pretty happy with both vendors.

Total price: $30

Build time: maybe 4-5 hours.

The challenges in this project were the adapter/heatsink and the optics.

The heatsink required me to cut a copper pipe in half and pond it flat, lapp it smooth and grind to the inner diameter of the light, to make the forward facing star mount.

Then I had to take a 3/4 " pipe and chop it to the right length, then make 3 cuts through it at 120 degree intervals. Then I broke off 2 of the flaps and bent the remaining 4 out slightly and took another pipe and fed it through the first and pounded it to till it had a flat surface

I then took the 2 parts and soldered them together with a torch, did some tweaking on the roundness of the rear flanges and drilled holes for the star screws and wires.

The optics were tough since the halogen bulb and lens are fused together and the total length, even if I cut the light out of the reflector it's too long for the heatsink. Instead, I grinded down a plastic lens, and took a plastic flashlight reflector and grinded it down as well.

Installing the electronics was easy once I figured out the wiring layout of the regulator. With everything mounted and wired up it works as well as my old 12W halogen, but with 5 modes and a very bright, long distance spot in 3W mode. I plan on adding a second beam, with flood optics and use a P7 or XP-G, but I don't need that kind of setup right now.
 

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Uzzi_PA said:
Has anyone else modded these lights? I've recently put together a light using an old style Marwi housing and clamp and a Cree LED. I have found that it's very very cheap and fairly simple to build. It also runs extremely cool, has a long battery life off of normal AA's, and has multifunctional settings......

.....I got the idea after seeing the success El34 has had, but I wanted to make my own heatsink and optics, because I like designing stuff and wanted to see if I could pull it off, without any help from a machine shop. All I used were spare parts from around the shop, and simple tools like a hacksaw, files, grinder, etc.
You have to love the look of the old Marwi halogens. I applaud your effort to make a simple heat sink to work with the XR-E's. Since I have a lot of old Marwi stuff at some point I might try my hand at DIY ( even though I have WAY too many bike lights now.) :D
The problem is there really is little incentive to cobble together a light seeing there are many cheaper alternatives. I am surprised though that you didn't chose to buy the P-7 kit from EL-34. With the kit you have everything you need ...heat sink, reflector, led , switch..etc..everything but the batteries and holder and you can get those from him too. Last I checked he had run out of the drivers so without the drivers you would be SOL. :(

(( ** EL34...If your out there and are still making those drivers let us know..;) ))
 

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Discussion Starter · #5 · (Edited)
Thanks for the advice guys.

You’re right about the price, I could practically get a Magicshine for a little more than I paid, but what’s the fun in that. This way I learned a lot about the tech, and was able to customize it.

I'm definitely going to try something like that for my next project. using a much brighter LED setup, and El34's conversion kit. Once it warms up I’ll want more light for night rides.

These old Marwi's are great because they can be mounted side-by-side on the same swivel mount and have full independent adjustabliIity; up and down and can even be twisted side to side for any handlebar offset. My idea is to have a XR-E spot/lowbeam, and 3 x XP-G's flood/highbeam.

I figured the low beam was a good place to start. I’m just commuting with this light, so I wanted a light that’s medium brightness for good visability and low maintenance. Using a P7 wasnt the best choice for this application. I also wanted something I made myself, so I understood how it worked and for the satisfaction.
 

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Discussion Starter · #6 · (Edited)
New Light Time!

Hi guys, I finally got my little XRE light working well enough to take it for a full-on night ride in the park. I replaced the junk home made optic with a DX 35mm reflector. Its now just enough light to pierce the darkness, but it's such a tight beam, I could only see a few seconds in front of me, which was a bit scary, going down super steep rooty and rocky down hills in the drizzling rain.

So now that I have usable light; why not rip it apart and build it into a new one? I'm making a dual XML out of it, which should give the night a run for its money.

I'm thinking it will work best with one at 3A with a narrow optic for the high beam, and the other at 1A and a wide optic for the low beam. I'm still waiting for the XMLs so I can see how they work with the DX reflectors. I cut one of the reflectors in half length wise so it makes more spill, and it looks good with the XRE.

Here's what the Old style dual Marwi looks like put together, but gutted out. You can see the new home made copper slug in the left side, which neatly press fits in, using some fancy soldering.
 

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Discussion Starter · #9 · (Edited)
The drivers and LEDs arrived last night so I was excited to start building it up. Here's the new setup:

Drivers: AMC7135 2800mA 5-mode, and AMC7135 1050mA single mode

LEDs: 2 XML-T6, 1D bin emitters

Optics: 2 DX 35mm reflectors.

Housings: 2 Marwi/Viewpoint bodies, with old style mount

Batteries: 2 Trustfire18650 2400mAh Gray, with home made parallel holder

2 Home made heat sink adapters; I made by cutting and bending/flattening copper pipe, then pressing the cylindrical part into the Marwi body (this part is critical for a tight fit) and using a torch to solder the flat part on.

Total cost of this build, minus wire and tools: around $115.

I purchased the parts from DX, hoffmanamps and Illuminationsupply

The build-up went pretty smoothly, I used arctic alumina adhesive to mount the emitters, instead of screws and thermal grease. I wired up the 2800mA driver using the 3 mode setting, so i get 150mA, 1000mA and 2800mA. The reflectors worked out better than expected; I had to shim both to got them to the right position, but the XMLs project a much larger light pattern that the XRE, so there is no ringing to the flood beam and the narrow beam is very bright in the center, but fades into tons of usable spill. I placed some tape over the top of the spotlight so its more friend to pedestrians.

It appears to be outputting the full amount of light and in distribution I had intended. That means about 400Lm out of the flood beam, and 870Lm for the spot light.

I'll post some beam shots, once I get everything focused just right.
 

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Discussion Starter · #11 ·
Ive just finished designing a new set of reflectors. The main one uses a reflective shroud, which reflects the light down, right below the focused part of the beam. I originally used a piece of electrical tape, but the 900 lumens started melting the black plastic, so I tried this trick and it worked so well I don't even need the second light head I built to point down and make a flood beam.

I couldn't get my point and shoot camera to do night shots, so no beam shots. I did draw a simulation of the beam pattern which you can imagine, when spread down the trail creates a large flood area that works well, even on the 1 amp setting.
 

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Discussion Starter · #12 ·
Finally got my camera to cooperate. I set it to ISO100, Daylight, and EV Shift +2 to get as close as possabe to MTBR settings, with my point and shoot camera.

I setup some sticks at 10, 20 and 30 feet.

The light works great, and I only need to use the high setting when going really fast, otherwise the 1000mA setting works just fine.
 

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Do you cycle thru your 5 different modes by simply clicking the light on and off with your switch? Also, I see on the IlluminationSupply website, the description of that 5 mode driver states, "Customers can request to have their board jumpered to 5/30/100 - just note it in the order". I'm assuming if I don't want the strobe and SOS option, only the 3 different light powers, I would ask for this? I don't see a Cree XM-L T6, 20mm star MCPCB on their site. Did you order that from someplace else?

Speaking of the driver, is this the one you have:

8xamc7135-28a-selectable-mode-driver
 

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Discussion Starter · #17 ·
Yep, the driver is pretty simple; like you said, it switches modes by turning the light off for a split second. With the Marwi switches, you can tap the switch slightly and it changes without having to fully click it off.

I didn't get mine pre-wired, but its an easy mod, because the board has pads on it that are easily connected, and you can select from several different configurations.

You can get it from IlluminationSupply or here too for less, but it will take a while to arrive from China. http://kaidomain.com/ProductDetails.aspx?ProductId=10995 The emitter probably sold out, their inventory seems to change alot, and I was lucky to get a decent bin there.
 

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Yep, the driver is pretty simple; like you said, it switches modes by turning the light off for a split second. With the Marwi switches, you can tap the switch slightly and it changes without having to fully click it off.

I didn't get mine pre-wired, but its an easy mod, because the board has pads on it that are easily connected, and you can select from several different configurations.

You can get it from IlluminationSupply or here too for less, but it will take a while to arrive from China. http://kaidomain.com/ProductDetails.aspx?ProductId=10995 The emitter probably sold out, their inventory seems to change alot, and I was lucky to get a decent bin there.
Did you have to remove the spring on the driver? Seems like it might get in the way with the lack of space we have in our Marwi newer style housing?
 

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Guys, thanks for the heads up on the 2800ma driver board.
I was not aware it was out there cause I never go to Kaidoman site.

I have been making my own from two of the AMC7135 - 1400ma boards

Question: I see that you can solder to the different stars and get access to the different modes. I am guessing that you use a Normally closed SPST switch, correct?

Then when you press the switch it breaks contact and changes modes, Correct?

Just asking if it's NC switch cause I already stock those, if not, I will have to get some Normally open switches (which I need to stock anyway)

Thanks for the info
 

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Discussion Starter · #20 ·
I did attempt to remove the spring by heating it up with a 50W soldering iron, but its on there pretty solid and I wasn't able to get it to budge. it didn't matter for me, because my bell style housing has all kinds of room in the back for wires, springs, powerbars, etc...
 
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