so this is the ugly looking pcb… i’m sure most of you have gone through this process!
I did the manual vias…had my 1st time hand-soldering 0603 components and they worked! The leds lighted up well and not shorts or continuity issues so far.
Managed to get a contact for solder paste which i can borrow tomorrow to reflow the microSD socket and maybe the FRAM (but most likely hand-soldering them)
So the only challenge left after so many challenges is… if i coat the exposed wires using nail polish and reflow the microSD socket tomorrow… will i end up with a connection again since the nail polish might be melted to?!
Really hoping that i have one soldered proper and ready to be attached to the core and test with the SD card library tomorrow night!!!
+1 for good tweezers. I like stainless curved tip Erem brand from Switzerland. Be warned they are expensive.
The 0603’s I can do OK but the 0402 and below I really need the microscope, but a good microscope is really pricey. One of those head mounted magnifiers is OK but not as stable.
any clues on the reflow temperature in general? But im thinking it should be quite specific since each component has a max time they can be exposed to the temperature?
I was going to comment earlier but I’ve been busy. You should probably reflow your SD card holder first if that’s the only thing you are reflowing, then solder down your other components by hand. Reason being if you do the card holder last your other components are getting re-baked so to speak and now you have to worry about all of them.
Reflow temps depend on your equipment really… and you need to develop a “profile” rather than some absolute temp.
When I was using a hot air tool, it seemed to work best for me to preheat my board and components to 150C, then ramp up to 300C until I saw that everything reflowed properly, then a fast ramp down of temps by backing off physically away from the board with the 300C hot air in an upward spiral.
If you have a hot air tool, I would just hand solder tack two points down on the ground tabs, and with solder paste on the pins already… hit it with these temps 150C/300C until it reflows.
So 150/300 im general would be fine? The data sheet didn’t mentioned about the profile unlike some others.
Yeah I was wondering about populating SD 1st or components but went ahead to practice soldering soncw I didn’t have the paste. I can probably redo the hand solder again after the reflow… haha!
After some sleep things get better! The original manufacturer has a spec sheet:
Basically the 150C/300C is great for my Sparkfun Hot Airtool… because it’s generating temps close to what a solder reflow profile would on the board. The temp of the air leaving the nozzle is not the same as the board. You’re equipment may be different. Here’s the profile from your datasheet:
It’s hard to mimic this by hand, but in practice you’ll find it’s good enough.
I really wished i had to chance to mess with all these stuff few years back and be better at it now!
I got pretty much everything i have to get going but there’s a last minute training since yesterday till thursday and sadly i can’t do anything on Good Friday!
Let’s see how i can squeeze some time during lunch =:x:
Yep, I’ll take 2 without the headers (I can solder those) and it could be shipped in an envelope too.
Is this going to be the new base size layout for Spark Core micro-boards ?
Very Nice Kenneth ! We need a kickstarter campaign for this but, it would be nice to have 1 or 2 or 3 more boards in the pot as well. Your Proto ? a Blue thooth ? or ?
I’ve been following this thread a long time and then I thought that I should also post my PCB board. Perhaps someone will get ideas or just can leave thumb up message
The leds lighted up well and not shorts or continuity issues so far.
is… if i coat the exposed wires using nail polish and reflow the microSD socket tomorrow… will i end up with a connection again since the nail polish might be melted to?!
core and test with the SD card library tomorrow night!!!
