The thickness of the stencil is supposed to determine how much paste is deposited. When you wipe the paste over the stencil excess is taken away with your card/squeejee.
Ok i get it, Nice thats why every of those paste jobs Dale did looked so pristine, i thought it was some special move required 
In trying to do so many at a time I wasn’t completely successful in holding the stencil flat down on the board, a few of those had thicker deposits of solder paste than necessary… one so much so that a resistor floated over and joined it’s neighbor! Other than that though it went pretty well, I’d never attempted that before and think it’s cool to see it happen.
That was really my point in sharing this, I’m not especially talented…if I can do this most anyone can! Give it a try! The pads are even large enough to do it with a soldering iron, it just doesn’t come out quite as neat. 
Ok, yeah you are right it is probably less complicated than it looks and maybe thats your point + I just read texaspyro’s post in Any interest in a CREE LED solder paste stencil? when he got the led stencils and that answered many of my questions on the led stencil.
I just want to ask is this driver efficient in low mode, like the LD-1 driver? I like the features of ld-1 driver but it’s very expensive.
- No, this driver is less efficient than the LD1 in the lowest modes. This driver is also completely unregulated. It is a very different type of driver than the LD1 which is a linear driver.
- A driver intended for use in similar roles to the LD1 is this one: 17mm double-sided & 20mm+ single sided 4Amp+ linear driver [A17LDQX]
- Other DIY drivers with good efficiency in low and moonlight modes are my A17PZL (17mm 8x7135 with Zener & dual-PWM) and RMM & Mattaus’s Moonlight Special V2 (post #1447).
Depending on your needs, I’d recommend looking at the A17PZL. It’s simple, well understood, and handsome. (RMM’s Moonlight Special driver may be easier to build by reflow, but I think that the A17PZL is probably going to be easier to reflow now that I’ve added the scallops around the edge.) The downside is limited current: Without stacking 7135’s you won’t do better than 3.04A. The first driver I linked to, tentatively named A17LDQX, is experimental and should be capable of the same drive currents as the LD1. Unfortunately it is much less compact than the LD1, requiring a two sided board with plenty of components on both sides.
For a better understanding of some different types of drivers we use, please read this thread by lagman: Understanding the difference between Linear, Buck, Boost and Direct Drive drivers.
You mean to tell me that the A17PZL boards that just shipped aren’t coming to me already fully assembled? Crimey! 
lol yeah yeah yeah, I know. worlds smallest violin…
> haven’t ripped an LED pad off yet
I’ve ripped a ground ring off the outside of a driver, after pressing it into a pill — while fiddling with soldering iron and bits of wire and solder trying to get it to properly ground to the aluminum around it.
To whatever extent vias help — and I’d think having some for little bits of copper wire to go through to engage with the pill — I’d cheer for whoever includes them.
Blame the old eyes and shaky hands, but hey, if a machine were doing the work, it wouldn’t be improving at the same pace. Glad y’all are doing this. Poking along behind trying to pick up some of the skills needed.
BTW, got any tips on how to unsolder a driver from a pill with just a soldering iron and some copper braid? I’ve removed as much solder as I can but the thing is still stuck. I don’t want to apply so much heat that I start melting components off, but it seems that some solder got down between the driver and the pill.
Am I just using the wrong tools, perhaps?
If there’s room in a wire hole to poke through with a tooth pick. Try knifing the remaining solder with an exacto knife. The solder shouldn’t wick to the side of the board so it’s probably just a tight press fit.
What driver/pill? It’s very uncommon (in my personal experience) to see a driver which is soldered to the pill from the inside. This definitely won’t happen just from solder running down the crack between the driver and the pill, it must be done one purpose.
If you can see joints and just can’t get the solder blob to separate (surface tension is keeping it together) then we can do something about that. In that case you can try to use a stainless or graphite implement to separate the liquid solder. An X-ACTO knife is a good tool for this. Solder will not wet to either material.
Good point RBD! In the case of a tight press fit where there is no alternative: comfychair mentioned in another thread that you can solder a wire onto the driver and pull on that. I’ve done it, it works. I’ve pulled quite hard on a driver to get it out that way. It’s scary, you could totally destroy the trace you solder to when pulling like. I tried to choose the largest copper pour available which was also close to the edge (so that I’d get good leverage).
Ideally you’d probably poke the press fit out from the top if possible.
Hmm… I hadn’t thought about cutting through the solder. I’ll see if that works.
This is an AK-47 driver in a UF-602C host, built by RMM. It’s nice, but I wanted to take it apart to reflash it. Remember when he tried to do 16340 EDC lights but the supply of hosts dried up? It’s one of those, after the better hosts were gone.
The driver is press fit into a brass adapter if I’m not mistaken, should be able to get it out if you hold your tongue to the left and squint your right eye while pounding a 1/8” drill bit through the LED wire hole in the shelf.
! I wasn’t suggesting cutting through the solder while it was solid, although that can be an option at times. Once the solder is liquid you can “divide” or “part” it with a stainless implement. If you push a stainless blade through a sphere of molten solder it will turn into two smaller spheres.
Like this? WarHawk-AVG - Convoy S5 and UltraFire 602C
Looks like WarHawk-AVG’s 101-AK was a loose fit inside the brass ring. In that case gently dragging an X-ACTO through the molten solder blobs should separate that driver nicely.
Woot! Cutting it (while solid) worked.
Anti-woot! The off-time cap is stuck directly onto a MCU pin so it’ll be a pain to reflash.
Anyway, thanks. Sometimes I’m really good at missing the obvious.
Edit: I think I might just pull it off and put it onto a different driver. I was recently hoping for a way to get an OTC or two to add to existing lights. Or maybe just put it on the other side, on a star. I think there’s just barely enough room to fit with a button-top battery. (the driver I wanted to put it on doesn’t appear to have room unless I air-wire it)
Good job! It shouldn’t be very difficult to remove the OTC. Take a look at my videos thread. I normally add solder to both sides and the cap is off before I know it. Be ready to remove it from the tip of your iron with a pair of stainless or bamboo tweezers.
I’m new here so forgive my ignorance but am I able to buy one of these (17mm) competed? My soldering skills aren’t the best and surface mount is something I have never done. Lets just say I’d prefer to just buy one completed. I was going to buy a BLF17DD from Mountain Elec. but they’re out of stock and I think this single sided driver is pretty cool.
If I recall correctly, RMM is planning to sell these soon, after he gets time to build them. Might be a little while though.
Otherwise, it’s possible someone in this thread might be willing to help. I suspect, if that’s the case, they’ll probably PM you.