What is a mechanical solder sucker?

[johnnyh55]

I read the steps to replace capacitors and the step 2 of the equipment needed found here:
https://www.badcaps.net/index.php?pageid=overview

says to not use a mechanical solder sucker, they can damage the board. I was planning on using a vacuum one like this

Is that ok? If it is, what exactly is a mechanical solder sucker, can anyone link to a picture of one?

[stj]

Re: What is a mechanical solder sucker?

that's one type of "mechanical solder sucker", the other is a plastic ball.

read this.
https://www.badcaps.net/forum/showthread.php?t=34998

[SteveNielsen]

Re: What is a mechanical solder sucker?

I'm not sure but I think the warning about using a squeeze-ball or spring-loaded sucker is that operation of it causes movement (how ever slight) of the sucker and in the hands of an inexperienced person can cause the soldering iron to move or bounce on the board, potentially damaging traces nearby. That said, I've used the spring-loaded for years but I can't say that I like them. I'd much rather have a continuous vacuum pump.

Another thing I'm not sure about is the recommendation that a 40W soldering pencil with fine tip will work. On a 6 layer board? Yeah, it might eventually but where caps are soldered to the ground plane traces you're gonna be heating it up for a really long time.

[johnnyh55]

Re: What is a mechanical solder sucker?

Well I was planning on using a solder sucker from radio shack to replace motherboard caps, do you guys think it will suffice? I did invest a in hakko fx-888d soldering station, I was hoping the solder sucker would be a minimal investment.

[stj]

Re: What is a mechanical solder sucker?

shack still exists?

[johnnyh55]

Re: What is a mechanical solder sucker?

Not quite, I refer to it as radio shack but in Canada the stores were bought out by Circuit City and were then called The Source by Circuit City and when they went bankrupt, BCE(Bell Canada) bought the stores and they are now called The Source. But they're still referred to as radio shack by many.

[SteveNielsen]

Re: What is a mechanical solder sucker?

I can't afford a constant vacuum desoldering device either (although I am trying to make one, still in experimental stages), so I use a spring loaded solder sucker. It doesn't always work that well and has to be cleared frequently but I can't say using it has ever caused any direct harm to me or what I was working on.

[diif]

Re: What is a mechanical solder sucker?

I've never damaged a trace either using mine (the end is a softish plastic) although they do annoyingly crap bits of dried solder into your board occasionally to remind you to clean them.

[stj]

Re: What is a mechanical solder sucker?

I can't afford a constant vacuum desoldering device either (although I am trying to make one, still in experimental stages),

i recomend you use an airhorn pump and an electronic relay as the basis.

[rhomanski]

Re: What is a mechanical solder sucker?

I just use a straw.

[SteveNielsen]

Re: What is a mechanical solder sucker?

I worked for a radio/electronic shop back in `75. The boss used an old canister vacuum cleaner duct-taped up to an automotive neoprene vacuum hose as a solder sucker. When it clogged up he'd cut the hose back.

I have a direct coupled electric motor piston pump I am trying to adapt. It is a nebulizer pump I have connected to the intake port a tube adapted to the body and tip of an old mechanical sucker and it works (very loudly) but I've got some leaks and it's a little clumsy.

[stj]

Re: What is a mechanical solder sucker?

weller DS80 used a pump very similar to an airhorn,
very fast to get 1Bar negative!

that's the other thing, fit a vac guage on a T piece so you can see how your pump is performing and spot blockages.

[SteveNielsen]

Re: What is a mechanical solder sucker?

I've look at vac gauges online too.

[johnnyh55]

Re: What is a mechanical solder sucker?

Well I was able to remove 4 capacitors but I was only able to get one hole completely cleared from the solder. I have tried using a piston type solder sucker and solder wick to no avail. I also had to add a little bit of solder to get the caps removed but some overflowed and are now touching the metal lines beside it. What would be the easiest way to clean those up? I am using 1.2mm solder, maybe that's too big?

Also any ideas how I can clear the solder from the remaining holes, I don't have a dentist pick on hand. I am using the chisel tip on my hakko fx-888d maybe I should be using a conical tip? Here are some pics of what I have done so far

[diif]

Re: What is a mechanical solder sucker?

Maybe you haven't got your iron hot enough ?
I use a chisel tip and mechanical pump. I add a little solder, heat the hole then slide the iron to the rim so the hole is exposed with the molten solder in. I get the pump in tight to the iron and click the pump, this should clear the hole.

[johnnyh55]

Re: What is a mechanical solder sucker?

I have the iron set at 842 degrees Fahrenheit, is that hot enough?

[diif]

Re: What is a mechanical solder sucker?

That seems too high, i have my cheapo iron set to 400c, turn it down and hold it on until the solder melts. Maybe practice on some scrap boards. It took me a little while to get my soldering right.

[ChaosLegionnaire]

Re: What is a mechanical solder sucker?

i use a safety pin instead of a dentist pick that is the same thickness as the hole. have a few safety pins of differing thickness for different sized holes. never seen the solder adhering to the safety pin. it must be made of stainless steel too.

never ripped out a via or trace after fully recapping three boards. (that means i've cleared over a hundred holes with the safety pin) never burnt myself either holding the safety pin to clear the hole. if the pin gets too hot, it means u are overheating the board with the iron!

[johnnyh55]

Re: What is a mechanical solder sucker?

That seems too high, i have my cheapo iron set to 400c, turn it down and hold it on until the solder melts. Maybe practice on some scrap boards. It took me a little while to get my soldering right.

Oh, I was following the recommended temperature listed here:
https://www.badcaps.net/index.php?pageid=cap_removal

i use a safety pin instead of a dentist pick that is the same thickness as the hole. have a few safety pins of differing thickness for different sized holes. never seen the solder adhering to the safety pin. it must be made of stainless steel too.

never ripped out a via or trace after fully recapping three boards. (that means i've cleared over a hundred holes with the safety pin) never burnt myself either holding the safety pin to clear the hole. if the pin gets too hot, it means u are overheating the board with the iron!

Good idea, I never though of using a safety pin. When I was removing the capacitor I was feeling it getting hot in my hand, was I overheating the board?

[johnnyh55]

Re: What is a mechanical solder sucker?

Also what size solder should I be using? And can I use the very end of the tip of the iron to solder or you have to use the side? It's kind of awkward to use the side with a chisel tip on something small, maybe I would need to use a conical tip?

Another thing I noticed is when I melt the solder in the hole with the iron, the solder comes up and follows the tip, as soon as I remove the tip the solder is already too solid to suck it up with the solder sucker.