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Do you hate blue resistors?
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exe:

--- Quote from: floobydust on March 26, 2020, 04:41:24 am ---Where's the power? 0402 good for 63mW. I can't work with little pepper flakes, too small for my eyes and the slightest bump sends them flying.
It's weird one consumer product drives the entire electronics industry towards the smallest parts, to the extinction of engineers being able to prototype something. In that sense, blue resistors are awesome.

--- End quote ---

I think so far there is a wide range of components available on the market: from beefy current shunts, to parts less than 0201. I use all of them (I mean both th and smd), TH for breadboarding and when I have to dissipate a lot of heat (hello to-220 and to-247), and 0603 when I have a pcb and I want to save some board space. I used to use 0805, but they are "too big" :).           

In my next project I'll try using 0402. I already have experience soldering them with a naked eye (on training smd boards). With a bit of practice it was actually not hard at all. But I wouldn't go smaller, at least not now.

I also have 0204 capacitors (reverse geometry), which I thought would be a great idea for bypassing digital circuits. But looking at the size of their pads, I'm not sure I'll manage. They are too tiny for me, and it looks like they are easy to short with excessive solder. So, probably, I'll use 0306.

I want to buy this kit, but it's not available: https://www.tindie.com/products/MakersBox/smd-challenge/ . May be I should just make my own version...

My advise for people who are afraid of smd because of the size: it's much easier than it looks, up to 0603 requires no special skills. 0402 a bit trickier, I suggest practice on an "smd training kit" before working with them on actual equipment.

PS smd tweezers are awesome. Can be used both for measurements and for placing if working with a stencil.
rsjsouza:

--- Quote from: floobydust on March 26, 2020, 04:41:24 am ---Where's the power? 0402 good for 63mW. I can't work with little pepper flakes, too small for my eyes and the slightest bump sends them flying.

--- End quote ---
Not only power but voltage as well. Slap an 0402 at the high voltage part of your power supply, immerse it in a humid environment for a few months/years and watch sparks fly. You can't beat physics.


--- Quote from: exe on March 26, 2020, 07:37:32 am ---My advise for people who are afraid of smd because of the size: it's much easier than it looks, up to 0603 requires no special skills. 0402 a bit trickier, I suggest practice on an "smd training kit" before working with them on actual equipment.

PS smd tweezers are awesome. Can be used both for measurements and for placing if working with a stencil.

--- End quote ---
I agree on the SMD training kit - these are very useful but could be replaced by old boards on a pinch.

But no special skills?!? The physical tolerances and marging for error are much narrower, requiring not only a feather touch hand but quite a few aids to help with the process, such as a loupe/microscope (stereo is even better), a fine pitch solder and soldering iron, spare flux and wick/braid for the occasional removal/resoldering of a part, kapton tape or other way to hold a QFP part in place...

You can solder a through hole part with a "fire stick" soldering iron featuring a 5mm tip half eaten by continuous use, filing it along the way to remove crud that accumulates as you go, whatever remnants of solder you have around and with a much heavier hand and a pair of reading glasses if you are aging. Some friends even used a clothes iron for the lack of a better thing available in an emergency.

Several years ago I have transitioned to 1206 and 0805 and, even when my eyesight was good, I still needed the optical amplification (loupe, stereo microscope) to be sure the job was well done (no solder blobs or shorts, proper positioning and alignment of parts). For the past year or so demand required me to move to 0402 parts and I can tell no special skills are required for this when compared to the 1206/0805, just a much lighter touch of hand.
exe:

--- Quote from: rsjsouza on March 26, 2020, 10:45:29 am ---But no special skills?!? The physical tolerances and marging for error are much narrower, requiring not only a feather touch hand but quite a few aids to help with the process, such as a loupe/microscope (stereo is even better), a fine pitch solder and soldering iron, spare flux and wick/braid for the occasional removal/resoldering of a part, kapton tape or other way to hold a QFP part in place...

--- End quote ---

Ah, I took this for granted  ;D . Also a hotair gun... The tool I really miss at times when dealing with lead-free is a bottom heater (though I woudn't say this is specific to smd, as I had troubles desoldering a TH-cap from a motherboard due to power planes). Also hooking test leads is a problem for me. Micrograbbers are expensive. I also have a spring-loaded needle-like probes, but I didn't manage to use them on 0.65mm tqfp, it's too easy to fall off (and short something).

I usually don't use a tape to keep parts in place, tacky flux help with this. But that's my personal preference.

My message was more like "embrace the fear". I was terrified by smd for many years, until just accepted it. Now I love it more than TH. It actually makes many things easier and faster (if the pcb is ready). Just put it on the board and bake it :).

My fears now are BGA, fine-pitched components, components smaller than 0402, and highly-integrated ICs with many legs, power sequencing, impedance matching, etc. I haven't dealt with them yet, but one day may time will come...
Mortymore:
I can't read the color strips over the blue. I ALWAYS have to measure them.   :rant:
I rarely have to do the same in tan ones.
Fungus:

--- Quote from: exe on March 26, 2020, 07:37:32 am ---My advise for people who are afraid of smd because of the size:

--- End quote ---

I'm not afraid of SMD because of the size, I don't use them because almost everything I make is a one-off or in small quantities so drawing a proper PCB, ordering it, waiting for it to arrive, etc., is a non-starter.

On the odd occasion when I do make a PCB I use through-hole because that's the parts I have in the drawer from the prototyping. If I used SMD on the board I'd have to order a bunch of duplicate SMD parts, too, so...  :-//

If you're producing en-masse or if somebody's paying you to sit in an office and prototype stuff then sure, SMD all the way.


--- Quote from: Monkeh on March 25, 2020, 02:49:02 pm ---What are these odd things with leads, anyway? Have we travelled back in time to the 1980s?

--- End quote ---

They're alive and well around here.  :-+
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