This clear picture from Dale helped me building one (edit:I see now that Richard's lay-out is slightly different) :
Man! You guys are lifesavers.
I built a second board and it works perfectly. The first board should have worked perfectly too except there was no info about the MCU placement.
I reflowed the MCU on the first board, and it’s working fine. I was afraid testing it with the MCU backwards might have blown something.
Once you pointed it out, even with my eyes, I can now spot that dot on the MCU from a mile away.
djozz dug up that great pic. I've posted some in the past as well, but tough to find them, probably buried in some of wight's threads.
That is a lovely soldering job on that driver. Mine never come out that clean. I don't know if it's something I'm doing or the type of flux or solder I'm using.
Mine come out look'n pretty much the same. Best way is to be conservative with the solder paste, pre-heat the board before doing the reflow. I use a hot air gun that has low air-flow, even spread.
It's not hand soldered, Dale does reflow as well, I believe hot air.
I must say, mine came out totally professional looking. My old paste was dried up, so I ordered a tube of Kester solder paste with a 22ga. nozzle. This is the best paste I have ever used. It has the perfect consistency and flows effortlessly from the nozzle. It melts fast and doesn’t bridge. It’s a bit pricey, but the shipping fee at digikey was so cheap I actually saved money buying more expensive solder paste. It was packed in ice and shipped overnight.
Nice Ouchy! I got a tube from Richard a while back I keep in the frig. He packed a large syringe completely full of Kester - I can't use that much in a lifetime, but tell you the truth, I've had small batch's in small syringes go bad, and this seems to stay moist forever - maybe because it is a big batch keeps it from drying up, dunno, but literally goin on more than a year, maybe 1 1/2 years on this syringe and still moist.
I actually don’t use a hot air re-flow, I use a hot plate on our glass convection stove top. Either a 1/8” thick 6” round piece of 304 SS or a 1” thick x 6” round piece of 6061.
I usually buy a stencil from OSHStencils.com, I use Kester Solder Paste and with the stencil I wipe it on with the supplied “credit card” The results are outstanding. 
I’ve done up to 24 drivers at once, with 2 sets of 12 on fully connected panels, then wired em and put springs on em and tested em while still intact. I always prefer to flash the MCU first, but it will flash after being built as well.
Here’s a pic of 20 all on the same panel…
Ahh - nice setup! Lot of history/info here:
https://budgetlightforum.com/t/-/30080 - wight's driver, very similar to the RMM one.
Pics in OP, Post #22 showing the solder paste, Dale's pic in post #78
https://budgetlightforum.com/t/-/27210 - my thread on the earlier OSHPark 17mm driver we were using at the time
OP shows the phases for reflow, good reference thread:
post #124: RMM's detail specs on voltage dividers
https://budgetlightforum.com/t/-/31102 - this thread is on the newer FET+1 boards
Also good reference thread - post #149 is a detailed pic (mine), not as good as Dale's though. Hot plate method is better
I wish I had a decent camera. My iPad just doesn’t go for macro component shots. I’d like to take a nice macro picture of this MTN driver, all built, with the components clearly legible. Then I could edit it with arrows and side notes to make it hassle free for first timers like me.
This is about as good as I could get from my iPad camera. Until a better one comes alomg for reference. There's a couple solder blobs where I had wires attached for testing.
Looks pretty clean to me, ouchy :)!!
Maybe take a pic at a sidewards angle so you can show the difference in the cap heights (which seemed to be the thing that we all get puzzled about, including myself).
Jim
I doubt I could capture that ohaya. Even side by side with a jewelers loop it’s pretty minimal.
Oh yeah, I should mention, supposedly, if you connect the pins at number three the UI should change from low - high, to high - low. I forgot to to test that though.
I just found an older digital camera that I forgot I had… an old Lumix FZ20. I wanted to try it on macros because it has manual focus, so I’ll post a pic in a bit if it comes out ok.
Jim
EDIT:
I think the difference in the height of the capacitors can be seen in this pic:
OUCHY - Can you confirm?
Thanks!
EDIT 2: OOPS! I just realized that the drivers I had from RMM are the FET+7135 - slightly different, so the locations of the caps vis-a-vis the MCU is different from the DD driver you have, but still you can see one cap is “taller” than the other.
No. The locations look pretty much the same as on my board. I don’t know if it’s the camera angle, but the taller one looks really tall in your pic. I had to actually place mine side by side (abutting) and peer at them through a jewelers loupe to tell the difference. Then again, maybe your capacitors are different.
You’re not mistaken. The caps I got are pretty visibly different heights.
Your 10uF capacitor is an 0603 whereas mine is listed as an 0805. Maybe that’s why.
Ouchy, the asterisk on the board marks the dot corner of the mcu. Dale, did you put the wires on those 24 boards before or after reflow and what kept them in place?
Rich , just checked an order (#13032) and it’s listed as shipped but no email has been received with the tracking number.
Ouchyfoot,
Thanks for the pics! I started putting these together today and they helped a ton!
Just make sure the little lines on the diode are facing toward the MCU.