MR11 HID conversion to LED

[lucca brassi]

Ah... OK

 

[mddolson]

It's been a rainy week, so I finally got around to machining the heat sink & assembling the guts.
My original design was 2 pieces but I opted for one this weekend. The whole aluminum heat sink is 1.5 inches long, 1.4 inches OD, the back end is bored out 1.25 diameter x .63 deep for the driver.
The driver fits in the cavity, insulated by a silicone rubber disk, it will be potted in place. I couldn't get #4 screws, so I used 6-32 button head screws to secure the LED star. Only unforeseen issue was the screw heads shorted the contacts, so I added plastic washers. I did have to relieve the optic holder at the screw heads (#6 heads higher than planned) It's tested & ready to be potted.

 

[Caveeagle]

Nice job, thanks for the update

 

[CGE925]

Thanks for the update Mike. I placed orders for the four components last January, received the optics from Digikey literally the next day, but the LED and driver only arrived from China in late April. Problem is, the driver board is bad, so after a 4 month wait courtesy of DX, I am back to square one. You mentioned that you had located a single mode/ON-OFF driver, any chance you got it from Canada, and could you tell me where you got it from? I'm finding that ordering from China these days takes on average about 2 months even from Ebay, and I'd rather not try DX again. US sources are available but shipping is getting outrageous ($20 shipping for a $10 item)

Thanks

 

[mddolson]

I found my drivers on eBay. They took only 14 days to arrive in the mail. This is the one I ordered, matched driver & led, just select the size & color:
when you select the driver there's an option for 1 or 5 modes.
It's a flash light driver. I just soldered two leads to the back side to extend out of my potting compound.

CREE XML2 LED T6 U2 10W LED Emitter 16MM/20MM Aluminum PCB+Input 12V LED driver | eBay

BTW, I slipped a pop-sicle stick under the star to solder the two leads to it.

 

[CGE925]

I found my drivers on eBay. They took only 14 days to arrive in the mail. This is the one I ordered, matched driver & led, just select the size & color:
when you select the driver there's an option for 1 or 5 modes.
It's a flash light driver. I just soldered two leaded to the back side to extend out of my potting compound.

CREE XML2 LED T6 U2 10W LED Emitter 16MM/20MM Aluminum PCB+Input 12V LED driver | eBay

BTW, I slipped a pop-sicle stick under the star to solder the two leads to it.

Thanks, looks like a good all in one solution. I'll give this one a shot and hope they get here before the end of the diving season ;o)

 

[mddolson]

Anyone know a source (preferably in Canada) for small quantities (50-100ml) of potting compound?
So far only found Scotchweld DP-270 in 3 oz tube (2 part epoxy)

 

[lucca brassi]

I would go with something like

Thermally Conductive Adhesives, Potting Compounds & Greases – Polymer Systems , you can order ''samples'' online ( 50-3100 , with 2.16 W/mK )

 

[Caveeagle]

I have bought small tubes of thermal grease at Radio Shack for setting up the heat exchanger on a sony plastation.

Wouldn't an adhesive/ epoxy prevent you from ever taking it back apart?

 

[lucca brassi]

If you have gel like putty (thermal putty) it is possible to remove it ( we did that with HID balast ) .

With epoxy-almost no chance (depends on epoxy type , but generally you destroy electronics , cables ...etc)

I put myself driver on similar aluminium or copper heatsink with double sided thermal tape and that it is .

Epoxy if it is not thermal conductive keeps electronics hot and prevent to cool down ( in spite of heatsink )