reinventing the wheel - DIY sinkpad idea

Very clever. Great idea and thank you for the picture too.

I guess you could also extend this through the pill and chamfer the back of the pill instead of the MCPCB. Then press them as unit. Reflow the MCPCB to the pill first. This combines Nightcrawl’s and Comfychair’s great ideas.

EDIT: Sorry, just noticed the OP said the above already.
EDIT2: Well, kind of. Press into pill, not press together. Sorry, again guys. I am multitasking to much stuff at the moment.

thanks comfychair, I’ll check to see if I have a 5/64in drill at home (I do miss metric!). I’ll have to have a think about how to do the pressing in as my vise grips are large’n’nasty (mostly used on the car), so I may do better to rig something up to use in the vise instead.

I was thinking something similar and you wouldn’t have to worry so much about getting the “rivet” on the back of the pill as flush. You’d have to be very precise with the drilling so that the LED was centred properly, but this and a thin layer of thermal great under the star would make a fantastic thermal joint. Then all you’d have to do is reflow the LED to the star once it was all together. I may try this with the C20 host I have coming, although my drilling is notoriously crap (no drill press).

Matt, wouldn't you just use your lathe to drill the hole? Unless its a multi-emitter you're going for.

Cool, please take pics if you do. I hear you on the drilling skills. I have a cheap HF press that I’m not sure will do much better.

I

Drill for screw holes to use just while setting it up... tighten the screws just enough so that the board won't slip on its own, but loose enough that the reflector can shift it into alignment. Remove, tighten screws, recheck alignment, then go to town drilling the rivet holes. Done! Well, you know what I mean...

Well, thats a different approach. My method is more suitable if you use a massive copper heatsink than for regular flashlights where you screw/glue the star down.

I would, but I can’t fit a drill chuck to my tail stock :frowning: I’m pretty sure drill chucks were invented by the time my lathe was made (if only just), but it has a non-standard tail stock. Can’t even fit a live center either. However, as soon as I make my milling attachment I should be able to do it the other way round, sort of like making it into a drill press.

will do! I’ll practice on some spare stars first though :slight_smile:

that makes perfect sense, although I may not have space for screws, unless perhaps I can tap the wire holes and use those? Would something like a very viscous grease (axle grease?) beneath the star to a similar job in centering the star, then I can use small C-clamps to hold it in place while drilling?

what I like about this “rivet through star and pill” idea is that not only will it provide an awesome thermal path but it will provide an excellent mechanical connection too, without having to go through the hassle of using screws. I’d even consider doing this for my bike lights, but I can’t see how I can heat up ~50g of finned aluminium housing enough to reflow the LED :slight_smile:

Whats your problem with centering? Pills usually have machine marks to find the center and on the star you punch-mark the center as good as you can.

I don’t know yet, this is my first ever torch/ flashlight host build :slight_smile: My main problem however is with drilling - holes never end up where they’re supposed to be, even when I counterpunch, as the general use bits I use (DeWalt, so 1/2 decent) can wander with my cordless drill.

Then pre-drill with a smaller drill or just turn the drill by hand at least for the first turns. Thats what I di and then I used a drill press. Its a lot easier with 2.6mm drills than with 1.2mm drills tho..

That’s a very cleaver idea.
Are you sure that you used 14AWG wire and not 12AWG. Every wire size diameter chart I have seen list a single strand (house wire) 12AWG as .0808 in diameter.

You can also use a drill diameter chart to find a bit close to the size of the wire you choose.

Ace hardware does carry the 1-60 wire size drill bits in my local store for making tap holes. They can also be purchased online individually from different sellers or ebay.

If you are using the optic to center the mcpcb then just use adhesive to fix the star to the sink, plunk it into the host with the optic, and when it’s set, take it out and drill the holes. Chuck the bit way into the drill to eliminate flex in the bit. Pretty sure 5/64 works with awg12. A bit of solder on other pads (added earlier) can help stabilize the file and add a visual reference. Flux the wire before inserting it to draw the solder in.

It is .080", checked with calipers. The 14ga number was just from memory of the last roll of Romex I bought, and since I'm poor I just assumed I never would have splurged on 12 gauge... but I guess I did! lol

no worries, I bought both 12 and 14 gauge copper wire at the weekend. It took some explaining when the guy asked me what I wanted it for! I have one foot of each, which should be enough to last me many many stars :slight_smile:

I won’t get to this for a little while as I’m in the midst of building my lathe milling attachment, which I’m super excited about, but I’ll post up pictures when I do.

Think I found a good victim. I still have sinkpads that are easier to use for most of my flashlights, but I think I found a candidate for the above procedure. My ZY-T08 has a big emitter base (something like 24mm) in order to clear the large reflector base. I don’t want to mod the reflector. When I upgrade emitter, I am going to try to do this. Already have the emitter. Just need to get the time.

neat, looking forward to the pics :slight_smile: You know you have a great idea when you find out someone has had it before you!

I propose that the copper-riveted aluminum MCPCB henceforth be referred to as the StinkPAD.

its already been done

well, my first one wasn’t a roaring success (StinkPAD is quite appropriate!) but I’m sure I’ll get better!