New Project!

13 posts / 0 new
Last post
Sirstinky
Offline
Last seen: 7 hours 46 min ago
Joined: 11/02/2018 - 17:07
Posts: 116
Location: Vancouver, WA
New Project!

So after some planning and debate, I decided to tackle this mod. It's a work in progress. The host is one of those pistol grip 1 million candlepower spot lights. It had a 55W H3 automotive halogen lamp running on 6V off a sealed lead acid battery. I realized the reflector wouldn't work with an led after cutting it down to get it to focus so I improvised and stuck a reflector in the reflector!

For power, I'm using a 3S2P battery with Samsung 25R's. I couldn't use old laptop batteries since it's higher current. I had to cobble together the battery to get it to fit in the host...its a prototype so not the final version which will have flat conductors connecting the series and parallel cells.

 

The emitter is a 5000k xhp 70.2 6V.

The wires pass through the heatsink. They're like that for testing.

The driver is a China special 5-mode 5A buck driver.

Since my host is plastic and not compatible with this driver (I bought it for a different project I scrapped), I had to make it work. I built a heatsink/ holder out of some laptop heatsink cooling pads, soldered and drilled out to hold the driver. I mounted it to the heatsink where the whole assembly will be fan cooled. Yes it works, but there are some kinks to sort out.

That's it for now. I'm waiting for another driver from China because I've killed two so far, but will work on the reflector more later. Hope you like this, and stay tuned for more!

Thanks

pinkpanda3310
pinkpanda3310's picture
Offline
Last seen: 3 hours 50 min ago
Joined: 12/28/2013 - 08:45
Posts: 1981
Location: Perth

Cool Cool Lookiing forward to this Beer

Relampago
Relampago's picture
Offline
Last seen: 1 hour 1 min ago
Joined: 04/14/2019 - 11:44
Posts: 386

Looks good, can’t wait to see the progress.

“Electricity is really just organized lightning”
― George Carlin

BillyBobJoe
Offline
Last seen: 40 min 27 sec ago
Joined: 03/11/2019 - 15:16
Posts: 70
Location: Western USA

Looks neat. Will the whole assembly fit inside the original case or will it need modified?

cayman
Offline
Last seen: 1 week 1 hour ago
Joined: 06/29/2019 - 13:16
Posts: 38

very nice project

Sirstinky
Offline
Last seen: 7 hours 46 min ago
Joined: 11/02/2018 - 17:07
Posts: 116
Location: Vancouver, WA
BillyBobJoe wrote:
Looks neat. Will the whole assembly fit inside the original case or will it need modified?

The only modification I’m planning for will be the reflector. It sticks out top far from the back, but once I cut the back down to make it with with the led, there’s more room.

DavidEF
DavidEF's picture
Offline
Last seen: 14 hours 6 min ago
Joined: 06/05/2014 - 06:00
Posts: 7195
Location: Salisbury, North Carolina, USA

Curious, what was the problem you had with the reflector that made it not workable? I started a mod on a “10 million candlepower” light some years ago, and the reflector worked fine with MT-G2. I did have to move the MT-G2 up into the focal point by making an Aluminum pedestal for the MCPCB to sit on. But I accidentally stripped the shiny coating off the reflector and finally couldn’t use it for that reason. I stopped working on it after that, and ended up giving the MT-G2 away after a while. I had about as good a focus as could be expected from any incan reflector. It was definitely better than the cheap halogen bulb that was there before.

The Cycle of Goodness: “No one prospers without rendering benefit to others”
- The YKK Philosophy

Sirstinky
Offline
Last seen: 7 hours 46 min ago
Joined: 11/02/2018 - 17:07
Posts: 116
Location: Vancouver, WA
DavidEF wrote:
Curious, what was the problem you had with the reflector that made it not workable? I started a mod on a “10 million candlepower” light some years ago, and the reflector worked fine with MT-G2. I did have to move the MT-G2 up into the focal point by making an Aluminum pedestal for the MCPCB to sit on. But I accidentally stripped the shiny coating off the reflector and finally couldn’t use it for that reason. I stopped working on it after that, and ended up giving the MT-G2 away after a while. I had about as good a focus as could be expected from any incan reflector. It was definitely better than the cheap halogen bulb that was there before.

That was the issue I ran into. I would have loved to see how you did that and made it work. And yes, unless you get into the hundreds of watts, a single led will make more light than an incandescent light source and a lot less heat per lumen.

Logistically it was possible, but I wanted to try the other way for yucks. I knew I would have had to move the emitter up into the reflector to compensate for the roughly 120-125 degree view angle from the led versus the 360 degree light dispersion pattern from an incandescent bulb. I didn’t want to mess with fabricating a pedestal to put the emitter on, drill holes in it for the leads, etc. and potentially damage the reflector. Plus I run my LEDs hot so I got better thermal management the other way. I hope this works!

DavidEF
DavidEF's picture
Offline
Last seen: 14 hours 6 min ago
Joined: 06/05/2014 - 06:00
Posts: 7195
Location: Salisbury, North Carolina, USA

I have a short piece of 25mm round Aluminum bar that I got from Dale (DB Custom) a while back and have used pieces of it for a couple of projects. This was one of those. I cut off a piece about an inch long and lapped one end flat/smooth for the MCPCB, and made the other end fit in the old bulb opening in the reflector.

The way I ruined my reflector was trying to polish it. I didn’t know it was a coating, and underneath was a clear (epoxy?) coating to make it smooth, then under that just junk metal. If I wanted to, I could sand away the clear coat and try to polish the metal, but it won’t do much good, and salvaging the light just isn’t worth all that work to me now for subpar results. Facepalm

The Cycle of Goodness: “No one prospers without rendering benefit to others”
- The YKK Philosophy

Sirstinky
Offline
Last seen: 7 hours 46 min ago
Joined: 11/02/2018 - 17:07
Posts: 116
Location: Vancouver, WA

They are all made pretty much the same way, stamped and spot welded sheet steel that’s coated with chrome then has an epoxy on the inside and outside for corrosion resistance. I found that out when I was grinding it on my belt sander…funky smells! I’d have liked to seen what the post thing looked like with photos of the beam pattern.

Sirstinky
Offline
Last seen: 7 hours 46 min ago
Joined: 11/02/2018 - 17:07
Posts: 116
Location: Vancouver, WA

So here's some tinkering I did today. Preparing to mount the base of the reflector to the heat sink assembly. I'm planning on fabricating a mount for the reflector as well. I'm trying to keep it modular for easy disassembly.

The aluminum ring is about 4mm tall and 35mm wide. It's a spacer that goes between the platters of a hard disk drive. Here it's a spacer/ mount for the bottom of the reflector. It sits on top of the heat sink. 

I could have spent a couple hours drilling holes into it and mounting it with screws, but why when you have JB Weld? I put thermal paste between the ring and heatsink since the reflector base will be aluminum and I will get some residual heatsinking. Yes, the bottom of the reflector is the top cover from a hard drive.

That's it for now. More to come! 

Best

Sirstinky
Offline
Last seen: 7 hours 46 min ago
Joined: 11/02/2018 - 17:07
Posts: 116
Location: Vancouver, WA

I got to do some more work tonight. I got my replacement drivers from China (stupid fast shipping from Aliexpress) so I resumed the driver mounting and electrical connections.

To do the ground strap I drilled a shallow hole in the driver holder and filled our with solder.

Then I soldered on an 18 gauge silicone wire that comes off the momentary switch to complete the circuit. 

It works! There's light. It gets really hot without the fan after about 2 minutes of turbo. 

I'll work on the reflector next. It's been raining so I couldn't work outside (wife says no belt grinding in the house).

Stay tuned. 

tirma
Offline
Last seen: 4 days 6 hours ago
Joined: 12/23/2012 - 10:58
Posts: 107

I am amazed with the great ideas I see in the forums. Interesting project