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This should be an interesting project. 1 chip soldered, 100 something more to go.

It's done, but I was missing a part. Or lost it. I'll never know, they're too small.

Check it out:
https://www.instagram.com/p/CNn7XLOAcph/

and the complete(ish) toy:
https://www.instagram.com/p/CNoRKc0gNy6/


I'm going to get some more practice boards like this. It was fun. You can't really tell from the videos or photos, but the soldering isn't as good as I want. Too much on most of the joints. I need thinner solder, and more practice. The chips came out great though, and that's what I was really after.

Thanks,
Josh

Nice work!

I'm not sure what soldering iron tip you're using. Many people say that a fine conical tip is best for SMD work. But I find a standard bevel tip to be much easier and gives great results. With the conical I always find that the very tip isn't hot enough but a bit further up it too hot, I'm sometimes moving it around trying to get the right spot and all the solder goes onto the component/pad. With bevel the solder pool stays on the flat bevel of the tip and transfers the right amount to the component/pad. The tip of the bevel is still fine enough for IC legs, not just SOIC like in your example but even individual pins of TSSOP. But for 0603/0805/1206 I used the side edge of the bevel against the component end cap and the right angle of the tip edge gets in much nicer than any conical will. I do all that with 0.5mm solder, although some people go down to 0.2mm

katopan wrote: ↑

Wed 04/14/21 7:51 pm

Nice work!

I'm not sure what soldering iron tip you're using. Many people say that a fine conical tip is best for SMD work. But I find a standard bevel tip to be much easier and gives great results. With the conical I always find that the very tip isn't hot enough but a bit further up it too hot, I'm sometimes moving it around trying to get the right spot and all the solder goes onto the component/pad. With bevel the solder pool stays on the flat bevel of the tip and transfers the right amount to the component/pad. The tip of the bevel is still fine enough for IC legs, not just SOIC like in your example but even individual pins of TSSOP. But for 0603/0805/1206 I used the side edge of the bevel against the component end cap and the right angle of the tip edge gets in much nicer than any conical will. I do all that with 0.5mm solder, although some people go down to 0.2mm

Thanks!

Conical tips are trash. I use chisel tips for almost everything. Typically I use a 2.4mm chisel tip, but for this I used a 1.2mm chisel tip. I have other tips too, but those are the main ones that get used (mostly the 2.4mm, even for turrets). I use an Aoyue 2703A+ rework station, and it's great. Though it's funny because they call chisel tips bevel tips on the SRA site. Oops.

That board I did has a whole row of 0402s, which was...fun? Hahahahah

Aaaaaaaaand I did that all with .8mm solder. I ordered some .4mm solder for the next boards. That should work much better.

I ordered a few more different SMD kits to work on. I'm going to solder one again, and I'm also going to use solder paste and hot air on another one. That seems fun, and way easier (if you don't blow the components away).

Thanks,
Josh

PS. For anybody reading this who isn't sure which is which:

For fine pitch parts, it's sometimes easier to solder across all the pins, then wick off the excess. The ability to solder individual pins depends a lot on the size of the tip and the solder. I agree about using a chisel tip, although professional assemblers do often use conical. Magnification is definitely required for the work and for inspection. We had binocular microscopes at work. I use a Donegan visor on the rare occasion that I work with SMT parts at home. This is the only application where I prefer no-clean flux to rosin core.

Jack

TriodeLuvr wrote: ↑

Thu 04/15/21 10:22 am

For fine pitch parts, it's sometimes easier to solder across all the pins, then wick off the excess. The ability to solder individual pins depends a lot on the size of the tip and the solder. I agree about using a chisel tip, although professional assemblers do often use conical. Magnification is definitely required for the work and for inspection. We had binocular microscopes at work. I use a Donegan visor on the rare occasion that I work with SMT parts at home. This is the only application where I prefer no-clean flux to rosin core.

Jack

I'm aware of the wicking technique too, but I try to avoid it. It seems lazy to me. lol

My 1.2mm chisel is close enough to the typical conical tip that I didn't have any issues, and the edge of the chisel is obviously even finer. My only issue (besides lack of SMD experience) was the thickness of the solder. It looks so tiny to the naked eye, but when I looked on the scope at solder pads, it looked like mountains.

I'm really looking forward to testing out the hot air / solder paste with the next board. That seems to wick itself into the right position from the videos I watched. I ordered 3 more practice boards, so I'll solder at least one of them by hand again.

The Andonstar HD208 I'm currently using is surprisingly good, and not expensive. I was impressed with how crispy the focus gets, and it's got a decent depth of field range too. I'm considering getting the HD407 or HD409 instead. They have HDMI output, and you can add optics to them to improve the visuals and DoF even more. I dunno if I need anything more than the HD208 though, so I haven't decided yet.

Thanks,
Josh

Hot air / solder paste is soooo much easier for SMD it's silly. Check it out: https://www.instagram.com/p/CN7ZXahAAUZ/

Granted, the LEDs weren't awesome later. Maybe I needed more paste? I dunno. I'm gonna go over those with the iron and more solder.

Thanks,
Josh

Magic