Hey guys, I am very new to this site and now I am part way through my first mod!
You may have seen the “Ultrafire W-878”
Now this cheapo light comes with a hollow pill
I wanted to drive this thing harder, but I was worried it would just burn up!
Now… how to solve the hollow pill issue?
I ordered a 3/4” rod of copper
and turned it down to the internal diameter of the hollow part of the pill (18.9mm)
Lets cut it off and see if it fits!
(I had to gently tap it in with a hammer so it’s a really tight fit).
Now, just require some holes for the wires now and to clean up the surface a little…
And now we’re done! Just need to put my new driver in (which hasn’t arrived yet) and also install my lovely XM-L2 U2 with copper sinkpad.
So guys, what do you think? Any tips you can give me?
Edit:Yikes! didn’t know the pictures would be so large.
I have changed them for smaller resolution pictures
Even though it’s a tight fit I would still use thermal compound. The reason is even though I trust your machining makes a perfectly round rod, I don’t trust the Chinese and their machines to turn a perfectly round part especially a hollow aluminum tube. Also the ridged turning marks wouldn’t be contacting the aluminum pill and so that’s less transferred heat. It’s also why it’s a good idea to put thermal compound on the pill when you thread it into the head.
Also what I would do is take some progressively finer sandpaper up to 1000 grit and a sheet of glass and lap the copper plug and star completely flat.
Doing the above should reduce led temperature and when I did it to just aluminum stars and aluminum pills I could easily run double the manufacturers currents and not suffer too much from diminishing returns on current vs light output. In other words where more current leads to less light due to overheating the led. Also running too igh temperatures will burn the phosphate. You’ll start seeing the areas around the traces on the die, especially where the bond wires are turning darker brown.
I have taken your advise and thermal pasted it and then tapped it back into position after giving it a sanding. I know it’s not perfectly finished at all and the groves for the wires are not perfect but it’s my first mod
You might want to drill and tap 2 holes to attach the star to the pill as there's no reflector to push it down. Or you can use thermal adhesive, but that makes later adjustments difficult.
An XM-L2 isn't going to produce a small spot in throw mode, though. You might want an XP-G2 or XP-E2, stock or dedomed.
It’s tempting! But there is a cap that screws into the pill (seen on 4th pic on the right) that holds the led down.
It had an XML t6 in it prior to these mods which seemed to focus to a very small square dot which didn’t bother me. I imagine the xm-l2 u2 will do the same.
Thanks, can’t wait to get my hands on the Convoy c8 I ordered!
I was going to just file them but I didn’t trust myself not to slip every other second and ruin the fit.
I ended in the end drilling 3 small indentations in a row as a guide for the file so it didn’t slip when making the groove. It worked, but it’s not as neat as I had hoped.
