Comment by jrockway | Hacker News Reader

Comment by jrockway | Hacker News Reader

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He seems to be mostly interested in building through-hole designs, which avoids the need for a lot of that specialist equipment. I do think you need a good desoldering solution for through-hole work, though, and he should talk about that a little. (For me, solder braid is always ... a relief? You struggle for a while and it does finally work once you are frustrated enough. Solder suckers are nice when they work, though!)

I kind of see where he's coming from but on the other hand, if you have some budget for hand tools, surface mount work is not as hard as you think. The Universe wants it to work; you heat up a board with surface mount components and solder paste on it, and entropy pulls the components to their correct position. So instead of waging war with the laws of physics, they're there to help you. A light touch and magnification are all you need.

I don't have a hot air station (or reflow oven) and I'm perfectly happy building surface mount designs. There are some things I can't do -- super small passives, BGA chips, etc. That's easier to design around than through-hole only.

My tip for the send-to-fab-and-wait workflow is to get someone to "code review" your design. Maybe they will find a dumb mistake and save you a week for a new revision.

Braid ALWAYS works if you know how to buy it, store it and use it properly.

Buy it -> chemtronics soder-wick. Do not buy anything else.

Store it -> store it in a zip lock bag not just chucked in your draw or crap box.

Use it -> Use an iron which can actually deliver energy quickly without overheating the workpiece (Metcal!), place the wick at least 1cm in from the end onto the joint and hit it hard from the other side in a iron, wick, joint sandwich until it stops creeping up the wick. Do not stop until it's done or it's game over for that joint.

99% of bad wick and soldering experiences are crap irons, crap solder and crap wick.

Tip: Solderwick goes bad after while.

I mostly agree with you but sometimes through hole joints just won't wick all the way because of the extra surface tension around the pin on the opposite side of the pcb. Not a huge deal if you can access it, but if you can't, like under an electrolytic cap, it's a pain. Even with my metcal and chemtronics wick. Sometimes preheating the joint can help but I almost always end up just destroying the cap.

If they are big cans like the old Sprague ones, I use a crap desolder station and the metcal at the same time. I wouldn't hit them with wick. That's for small components.

Question - you mention caps, I've always found them to be the easiest component to desolder. Just heat one pin and rock the cap using your other hand, sometimes you need to rock back and forth several times if the layout is tight, but this method applies way less heat to the board and cap. Once the cap is out, even one of those useless solder suckers will easily clean the hole in the board. You pretty much need to have a vise or some sturdy way of holding the PCB where you can access both sides, but this works way easier and doesn't destroy the cap or delam the board.

Yeah through-hole you want a desoldering gun. Using a wick is too much work for that IMO.

Something I've found that helps is to snip off a section of wick and hold it with a pair of ceramic-tip reverse tweezers so you don't have the rest of the roll leeching heat from the section of wick that you are using.

>Solder suckers are nice when they work, though!

They are great things once you learn their quirks.

Cut a notch in the nozzle that is slightly smaller than your iron's tip, a few uses will mold that notch to your iron's tip so you can keep the iron on the joint when sucking without affecting the seal.

Add more solder to the joint before sucking, this will help get a good seal as the sucker's tip will sit in that solder. The sucker will have no issues getting the excess.

Don't force sucked solder out through the nozzle, if the piston is more difficult than normal to depress than unscrew the end to clear the solder, forcing it through will only distort the nozzle and shorten its life.

Take the time to clean and lubricate at the end of the day. Bits of solder which get trapped in the sucker chew up the o-rings and ruins the vacuum. Take it apart, run a small stiff bottle brush through the body a few times to remove any solder, remove any solder in the nozzle, clean the plunger. Apply petroleum jelly to all threads and the plunger, reassemble.

If function quickly degrades after cleaning/lubricating than your o-rings are worn, replace them. O-rings are cheap, keep a supply on hand.

All good pieces of advice.

I also want to throw out a recommendation for this sucker in particular: https://www.engineertools-jp.com/ss02

I kind of impulse-bought that recently and had to repair a device where the AC line cord was damaged and is soldered directly to the board. I heated up the joint and sucked out what seemed like a gallon of solder in one go; the wire then just fell out with no problem. I was very very impressed. For $22, worth having in your toolbox if you ever interact with large quantities of solder that may be to removed.

I concur. It works exactly how you expect a solder sucker is supposed to. It gobble up the solder so good it's a joy to use.

I regret not having known about this tool years ago. I wasted so much time and frustration on the ubiquitous cheap solder sucker. It's a world of difference.

Be careful with these. If you use one with a crap iron or overheat the joint it'll suck the traces off the board too. They should only be used with a decent temperature controlled iron.

Sucking solder without temperature control is no different than soldering without temperature control. If you are not good at spotting when the solder goes liquid or using a sort of solder which is difficult to see when it goes liquid than just apply solder as you heat it as you would if you were initially making the joint, solder touches the pin and not the iron's tip, when the solder starts to flow put down the solder and grab the sucker, suck. No need to rush when getting the sucker, you have a second or two still before the entire joint has gone liquid and a few seconds after that before you are at risk of overheating assuming you are using a properly sized iron for the job.

This company also makes amazing pliers!

Check this vid for de-soldering w/o hot air [0]. Lots of flux and some heat spreaders.

[0] https://www.youtube.com/watch?v=CVsmwFAkf7I&list=PLYG9UdJdXi...

I also like that Chip-Quik solder that stays molten for a long time; apply it to every pin, lift off chip.

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