Well, as I continue to look at moving to smaller components for my SBC projects, my tools are sorta like me.... old. I've been using Weller soldering irons/stations for over 50 years. The WTCPL station I bought in 1977 is still in use (gave it my brother over 18 years ago). Meanwhile my older EC3000 had fried it's control board due to a short in the handle cable... so I just repaired it (new updated control board and a new old stock iron I had). I still have a pair of newer WTCP stations and just gave a barely used Hakko FX-888D to my older daughter. Despite the ones I still have, none are quite small enough for the really small components. Then again, most of what I built up years ago was vacuum-tube audio gear.... big parts!

So... as I'm still a Weller fan, I finally broke down and bought a new WX2022 set (Mil-Spec). It came in today... in a word, lovely. As a kit, it came up the WX2 supply unit (which will handle two irons), the Pico handle with a tiny chisel tip, the stand/holder, some nice tweezers and even a small roll of lead-free 0.2mm diameter solder. I'll likely get a second larger iron to pair up... mainly for soldering larger stuff, but that will be later.

My next tool for SMT work will be a Stereo Inspection Microscope, still doing some research on that one. But I'll also look at a better PCB holder going forward and a few other specialty tools. In any case, just thought I post this and perhaps others will chime in on what they're using for SMT related work.

Teaser pic attached....

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Regards, KM
https://github.com/floobydust

I've used a WS50 + MLR21 from 1999 to 2017. That pair got a massive amount of use in that period. After 10 years of full on activity, I did have to replace the iron, because of some freak cable trouble. Still used as a spare.

Replaced by WX2021 in 2017. Again excellent. Not cheap. But if you use it extensively (and I do) it is totally worth the investment. WXMT MS is a great little tool for quickly and cleanly removing various SMT components. I added (but rarely used) a WXP120, which is more of a 'just in case' for any truly rough work.

I would recommend anyone, these days, to at least go for a 'micro' type iron. I've never understood why many people seem to do everything with an iron that is okay for DIP but is way oversized for these day's smaller components. A WXMP MS (for example) has enough power to handle everything from SMT up to connector lugs, and is far more precise in use.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

Early part of my professional job was a production engineer. All the assemblers were using Metcal soldering station and worked under Zeiss stereo inspection microscope. They were too expensive new so I bought mine on eBay back when eBay was young (I'm an eBay member since 1998). I still use them, everyday. My most precious possession for SMT work is a roll of 0.0092" (0.23mm) solder wire acquired from local salvage store, had that for over 20 years and hardly used 1/10 of the 1 pound roll. That's a good thing, because it is pretty much unobtanium.
Bill

I have that one too. Two rolls, one 0.23 mm (250g), one 0.9 mm (500g). That's what I've always used. I don't even remember when I bought the 0.23. But the 0.9 I have to buy again every 5 to 10 years. 0.23 mm seems to be still available though.

For the fairly small amount of SMD soldering I do I get along alright using a fine-tip iron -- and sometimes desoldering braid, as BDD mentioned. But removing SMD parts remains somewhat challenging.

When removing a through-hole IC (.1" pitch) I typically nip all the pins and remove the body; then I can desolder and remove each individual pin one by one. The goal is to avoid damaging the board (I'm not trying to salvage the IC).

Of course the pins on an SMD chip are too small to nip with hand tools (cutters), but I have a Dremel bit which could probably do the job -- haven't tried this yet. Reminder: in this and any other case where metal fragments are generated, take pains to ensure they get removed as they could cause a short if they end up lodged in the board.

The other removal approach involves de-soldering, which gets tricky when there are lots of pins involved. Has anyone used hot-air devices for this? Is there an entry-level tool you can recommend? Cheers.

Jeff
ps- here's an illustration of the Weller WXMT MS which Windfall mentioned.

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In 1988 my 65C02 got six new registers and 44 new full-speed instructions!
https://laughtonelectronics.com/Arcana/ ... mmary.html

I have an inexpensive (<$50) 858D hot air station to remove parts I want to save. In crowded board I would fashion an air-dam out of a strip of copper so adjacent parts won't reflow. For fine pitch SMT like quad flat pack that doesn't need to be saved, a X-Acto knife can easily cut off the legs from the body.

From my board production days, I've seen experienced assemblers removed quad flat pack one pin at a time and re-solder it to another board, quickly. I'd missed it if I blinked and then I can hardly tell it had been reworked.

Eye protection is good when doing this...

Recently I've used hot air, but mine is not an entry level tool (Weller WTHA1).

What I've often done before (and still do), is use a small needle : very gently push it under the pins and alongside the chip body, creating a slight upward force, and then heat up the pin with an iron to lift it. Next pin. Needless to say, subtlety is essential here, or you'll lift more than just the pins ...

I've also used an exacto knife, very gently cutting the pins exactly where they enter the chip. I've found that SMD pins tend to cut surprisingly easy this way. Then desolder the individual pins and clean up.

I have a Milwaukee Precision Hot Tool Model 1400. It's a small heat gun intended for arts and crafts. I bought mine used on eBay USA for around $20 shipped. There are usually several similar "Buy It Now" listings at any given time. The tool is not designed for surface mount rework but it's inexpensive and I have used it successfully to desolder quite a few LQFP and TQFP parts. The radio in my car has an MCU that I desoldered with this hot air tool and soldered back in later.

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- Mike Naberezny (mike@naberezny.com) http://6502.org

Thank you, all, for your replies.

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In 1988 my 65C02 got six new registers and 44 new full-speed instructions!
https://laughtonelectronics.com/Arcana/ ... mmary.html

I got one of these: https://tinyurl.com/2ahxedvv

A cheap and effective unit with iron and hot air.

Mine also came with a tweezer iron which is great for removing larger passive components.

My old Hakko iron plugs right in and works a charm too. The iron that comes with it is okay, but not as nice as the Hakko for every day use. I use the iron that came with it on my old Hakko power unit with a big tip on it for when I need a little extra thermal inertia.

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Bill

Under the 'overkill' category of tools, I use my old lasercutter a lot. I cut stencils for solderpaste, which allows me to play all kinds of tricks for really dense parts - such as cutting slots instead of lots of tiny holes (when reflowed, paste is drawn into the pads). Varying the width of the slot allows me to deliver just the right amount of paste. I do all SMT ICs that way.

Click on image and zoom in for a closer look!

By the way, I cut disposable stencils from old paper mailing labels. I got a big roll at some yard sale years ago, and they happen to be just sticky enough for a perfect attachment to the board for creaming, yet come right off. They also have a glossy surface and are perfect in thickness, and in fact, in every way. I don't know what I will do when I run out, but I will probably be dead before that.

I experimented with reflowing boards in the lasercutter by illuminating each pad to heat it. It worked extremely well, but required a lot of trial and error to initially figure out how much energy each spot requires. It was somewhat slow, but most of laser cutting is pretty slow (except for paper stencils which are fast!). I didn't do much reflowing as the fumes produced are likely to damage the mirrors, but it was an amusing experiment.

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In theory, there is no difference between theory and practice. In practice, there is. ...Jan van de Snepscheut

The best tool for working with SMT is keen vision...which leaves me out.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

My vision is getting crappier all the time, but I am not giving up yet. I am developing all kinds of tiny black spots that fly across my vision field, and weird local distortions. It is very frustrating. But the worst is a https://en.wikipedia.org/wiki/Scintillating_scotoma, which is completely crazy and makes it impossible for me to do anything for the rest of the day. Luckily I've only had it a few times. Apparently it is a migraine symptom, but sometimes happens without a headache (as in my case).

I have a stereo microscope (for which I need to build a real LED illuminator), a couple of little camera microscope USB devices, and a variety of magnifiers.

The microscope is old and a little hard as the image darkens unless my eyeball is exactly in the right spot in front of the ocular. I should really get a proper industrial microscope with a camera. One day.

My favorite magnifier is a cheapo visor-style one with (pre-led-era) tiny flashlights which I lost the covers for long ago and never use. The magnifier has a flip-down secondary lens, is entirely filthy and scratched, but I use it all the time! I can fit my glasses with astigmatism correction under it.

I also bought dentist-style binoculars with eyeglass frames. These are interesting because they focus 2-3 feet away, which sometimes saves your back and gets your nose off the workbench, which is probably not that clean. But because of my astigmatism they are hard for me to use as they are quite good and I expect a sharp image! The crappy magnifier is so bad that I expect nothing, but I can wear my regular glasses underneath.

I also have an eyeglasses-with-removable-plastic-lenses kind of magnifier, with a set of 4 or 5 lenses. The optics are crappy plastic but they work fairly well for short stints. They are a little heavy on the nose and leave a mark after a while.

Good lighting is essential. Luckily we live in the golden age of LEDs. I have powerful worklights, and some multi-led stick-on strips to light up the operating theater. The trick is finding ones that are not pulsing slow enough to be annoying when scanning across them.

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In theory, there is no difference between theory and practice. In practice, there is. ...Jan van de Snepscheut