I've found that there is a HUGE variance in quality and effectiveness with the handheld solder-suckers; the original full-size Solda-Pullt is still the yardstick. People complain that it's too big; and it can be unless you're willing to do the disassembly necessary to be able to heat the pad & move it into position quickly. But that size is what makes it effective; you need that volume and big springs to develop useful vacuum.
One of my first China-direct purchases, back in the late 90s, was a couple of knock-offs of the full-size Solda-pullt; I figured for what they cost (2/$9 with shipping from DHGate or DealExtreme), I could have one and a spare and still be money ahead. They were TOO GOOD a copy; aside from the branding ( Zhong-Di ZD-108 ), they were the same all-nylon construction, with 1/4-turn disassembly and even a spare Teflon tip. 20 years later, I still have both of 'em.
I have a good power desoldering station in my Aoyue 2702; it works well but is just a lot more hassle to maintain than the ZD-108.
mnem
*off to take a handful of pillz*
Yes, powered ones are far more difficult to clean and can be slow to heat up but there is nothing like them for big jobs and speed especially on large parts like multipole connectors for example. I have tried heat and wick with wiggle, manual suckers, even have a manual sucker which is heated directly and nothing compares to the powered sucker in my book. I've damaged traces and pads with wicks using heat and wriggle method with wriggling lifting or even tearing traces.
Yup... that's why I still have the 2702. I follow a few simple rules: Use a big enough iron at the RIGHT TEMP FOR THE SOLDER, work quick, don't try too many times, move on to the next tool in your arsenal. If the sucker doesn't work the first time, apply fresh solder/flux & try again. If no joy, then time to move on to the power station, take time to set it up right, then try again. Usually you'll get to where you can wiggle the leg in the hole with a touch of the iron to just the pin. If still no joy there, time to move on to destroying parts & extracting pins. As always, you use your judgement as what is the likeliest route to success.
If the part is a dip or QFP, I usually cut the legs flush with the package using an X-Acto knife, then extract the remains using tweezers & iron. Fucking VIAs and microscopic pads will always pull apart otherwise. (Yes, I know I still have the CMOS battery on the board; I didn't care because
"Hello! Chip was dead already!", and I didn't want to lose the coin cell on my horror of a bench while I waited for the new chip to arrive.)
The single most important pitfall I can think of is DON'T CHEAP OUT ON YOUR SOLDER-WICK. Chem-Wick is the only one I TRUST TO RECOMMEND; no other brand has "Not let me down" with QC issues at one time or another. You CAN buy cheaper stuff but you HAVE TO TEST IT EVERY TIME, EVERY ROLL on scrap boards and often your technique has to change to be able to use it successfully.
When using solder-wick, DO NOT BE TEMPTED to turn up the heat. Use a bigger iron AT THE RIGHT TEMP FOR THE SOLDER. This is the only way you keep from wiping microscopic traces off the board with 0.5mm pitch QFPs and such. This is a STM32F205 in LQPF100/0.5mm pitch that I did completely by hand with iron (
My MLiNK S4, back when it was brand-new and magical and I was still in love with it
) and drag-soldering to reinstall. Sorry for the crappy finished pic, but the only one I could find post-op was a crop of the board after my WS2812 mod.
As a manual desoldering pump I have this one (the ss-02 model): Can be found here: http://www.engineer.jp/en/products/ss01e.html or on Amazon
And the more sophisticated one is this one: https://www.tme.eu/en/details/sp-1010dr/desoldering-stations/solder-peak/
I've had a number of the aluminum-body solder-suckers and never cared for them; too small, not enough vacuum. Single-handed operation is easy; just a matter of changing your workflow. I've gotten in the habit of placing my trash-can under the bench just to my left (or right, as the work demands) whenever I do rework. I just push the plunger up against the bottom of my workbench; it dumps the crap right into my trashcan and I don't even have to reposition my hand off the trigger button. You do it a few times and it becomes almost an autonomous function.
But I DO like the idea of that silicone tube as a consumable "sealing element". I need to see if I can mod one of my ZD-108 blue beasties that way.
Your desoldering station is pretty much identical to the one built into my Aoyue 2702. Again, more assache than it's worth most of the time.
The outcome depends on the annular ring size, track sizes and the via quality. If you look at the high density boards none of those are in your favour.
Quite so.
Still, there are many that use default annular rings and drill sizes and are too inexperienced with rework to know how big a difference just these simple things can make.
I've given up critiquing PCB's here as advice on this seems to fall on deaf ears.
I only hope these novices have to rework their own designs a few times to get them to work and then learn from the school of hard knocks !
Indeed. I think most professional "design engineers" tend to just chuck the board over the fence and not give a shit.
They should spend some time fixing shit. And make them use a firestick and a Tandy solder sucker just to hurt them 
Quick case study. QRP Labs QSX. Check out the pissy little pads for the encoder pins, the tiny annular rings everywhere and the worst of all, the clear bad soldering on the header pins on the rear of the board due to the drill size vs pin size - the solder just sits on the top and there's hardly any annular ring. Ick! The pads are so small it's no possible to hand solder them properly. Bugger one and the whole board, including all the prepopulated SMD parts go in the bin.
I've got this one unpopulated but look at the huge difference. This was designed to be fixed: 
There is no excuse for the former not to be like the latter. Edit: another really good board: 
THIS! 1000x THIS!!! One of my first jobs as an engineer I was the "young guy" they always sent to the floor for troubleshooting, rework and process control. Time and again the problems revolved around trying to make it too compact. The application didn't need it; we had oodles of space to work with. It was simply trying to get as many PCBs out of a sheet as they could. They were working with older parts placers, and their precision wasn't that great. They had unskilled labor force and high turnover, because they weren't willing to pay for skilled workers. So rework rate was high, as were the number of "holes" in the conveyor due to stopping to clear jammed placers.
Just by actually listening to the workers and what they had problems with, we revised the design to lose 2 boards per sheet, made the boards approx 10% larger on one edge, and used the space to decrease density so we could use the right size drills & pads (slightly oversized so our older machinery and unskilled workers could "hit da ho' " the first time instead of the board needing to loop through or go to rework) and actual productivity increased by almost 40% just because we weren't breaking parts placers and a backlog of rework boards all the time.
Sometimes you need to hit the bean-counters where it hurts to get their attention: right in the beans.
mnem
*Feeling almost-human*
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