Step 6: Glue the LED's

Picture of glue the LED's
the glue is all we are using to hold down the LED's. it seems tough and durable to me, but if you are worried the alternative is for you to drill 2 holes in the heatsink for each of the LED's (matching the cutouts in the star), and bolt them down with 4-40 size nylon machine screws. (or 3mm size). you can get nylon machine screws from www.mcmaster.com

1) do not get any glue on the LED lens. some glues (like silicone) you can get off the lens after it dries.

2) make sure the glue can handle 80-100 degrees celcius. (don't use hot-melt glue!). make sure it is waterproof (don't use superglue / cyanoacrylate)

3) i used silicone, but if i do it again i will try epoxy instead. the silicone does not flow by itself, so it is hard to get it to fully cover the LED (in order to have a submersible lamp). with epoxy you can dispense it with a syringe and accurately get it everywhere but the lens. smearing the silicone around is messy.

4) after pouring the glue, press the lens holders into place on top of the led's
I added thermal compound between the LED's and Heatsink while opting for the screw method. Better cooling = brighter LED.
rmccurra7 years ago
I opted to use the nylon screws as this seemed like a more stable/cleaner solution. However, the bulb holder interferes with the screw heads. Also, it appears that the bulb holders do not snap securely to the led stars. What are my options? Thanks.
dan (author)  rmccurra7 years ago
ugh! perhaps you can shave down the heads with a file or sandpaper, or use flathead nylon screws instead of regular head?
rmccurra dan7 years ago
Trusty dremel has worked fine. I now notice that the lens holders don't snap in place. Is silicone the best adhesive or can I use epoxy (2 part). I'd like to stay away from lots of goop. Thanks.
dan (author)  rmccurra7 years ago
yeah the holders just fit on, must be glued. either glue should be fine.
rmccurra dan7 years ago
I used Duco cement to tack down the lens holders and will follow up with silicone to cover wires and seal/hold down the base of the lens hloders. Is the Duco ok for this application? If not, my thouht is that it will a least hold the lens holders in postion so I can goop well with the silicone. What do you think? Thanks.
Dilute the GE silicone-2 with mineral spirits to thin it down. That should work, but forego the urge to flip the switch before it's dry!
dude where did you buy your silicone, and how much do you think you need for this project? Just got my parts in today, this project is awesome, well done.
dan (author)  John Culbertson8 years ago
standard GE SIlicone-2 from home depot. the smallest tube will be way more than you need.
radiorental8 years ago
If you use epoxy you can protect the lens with heavy duty packing tape.