Your best method for removing thorugh-hole components from a PCB

andare

Well-known member
Hi,

I'm trying to remove a 47uF electrolytic capacitor from a Minnow PCB that is 99% populated. Silly me soldered it where the 4.7uF cap goes...
I'd like to salvage this build because it is expensive and complicated for me but solder sucker and my puny 0.5mm solder wick aren't working.

What is your go-to method from removing through-hole components from a PCB?
Should I just use wider solder wick? 2mm?

Thanks in advance!
 
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Unless it's a super valuable part, I cut it out because it reduces the risk of damaging the pcb. You won't need as much heat to desolder. Then the problem is reduced to removing the solder and the little bit of lead left.

It's possible to do it even with one of those cheapo suckers. I put the board vertically, and place the solder sucker on the under side, with the tip flush against the pcb. It needs to create a vacuum to suck. Heat the component side with the iron, and start triggering the sucker once the solder is moving. You might need to pop it a few times to get everything out.

There are more precise tools for the job, but that's how I do it with the commonly available dingus.
Unfortunately the cap is right in the middle of the PCB and there's no way I can reach the bottom with cutters or the iron.
 
I usually hit it with the solder sucker then wick the rest out... taking my time sometimes the components with just fall out. I have learned the hard way a few time if you try and force things and rush you are going to screw up.
 
First I use a sucker to get as much solder out as possible. Then I heat again to pull the component out.

Once I get the component out, if there's solder plugging the hole, I push a needle through while heating the pad. That usually clears it out.

I also usually end up stabbing myself with the needle. That part is optional, but it's a good reminder to double check the component the first time.
 
And it never hurts to check the board with your DMM after removal to make sure you didn’t F up... in the event of a future troubleshooting issue you know that the board isn’t the problem... first hand experience: when that sucker doesn’t work right and you didn’t check the board that the first thing that popped in my head... it wasn’t the issue but still... that piece of mind is priceless.
 
And it never hurts to check the board with your DMM after removal to make sure you didn’t F up... in the event of a future troubleshooting issue you know that the board isn’t the problem... first hand experience: when that sucker doesn’t work right and you didn’t check the board that the first thing that popped in my head... it wasn’t the issue but still... that piece of mind is priceless.
What do you mean exactly?
 
When I’ve pulled parts on pedalpcb boards (which I’ve done a few times, and luckily it’s usually just been mods rather than mistakes), I hold the part from the component side, heat the pad on the solder side, and lightly pull (not hard).

resistors are easy since you can bend the lead as you lift it up. Caps are harder since the other leg holds it solid. Usually I have to go back and fourth between each leg, pulling it out just a little bit at a time. Haven’t killed any pads yet, luckily.

08UDZ8f.jpg

Not very helpful, but it is my best method. ;)
Hope you get it fixed.
I saw someone remove an 8 pin op amp in about 10 seconds with one of these once, and I’ve wanted one ever since.
 
I like to use these now

These are the way to go... I find that anything soldered to the ground plane is the problem. Did you notice that one lead of your cap moved easier than the other? I had this problem yesterday with a power supply cap on a board I'm working on... The cap was fairly easy to take out (caps are easy to remove because the leads are so close together, you can heat both leads at the same time with a chisel tip iron) but clearing one of the holes (ground plane) was nearly impossible to do. Wick won't do it and a solder sucker won't either. What does work is those SS fine point desoldering tools but a 3rd hand is needed. Another thing that works well is compressed air coming out of a very fine point, but this method is messy.
 
These are the way to go... I find that anything soldered to the ground plane is the problem. Did you notice that one lead of your cap moved easier than the other? I had this problem yesterday with a power supply cap on a board I'm working on... The cap was fairly easy to take out (caps are easy to remove because the leads are so close together, you can heat both leads at the same time with a chisel tip iron) but clearing one of the holes (ground plane) was nearly impossible to do. Wick won't do it and a solder sucker won't either. What does work is those SS fine point desoldering tools but a 3rd hand is needed. Another thing that works well is compressed air coming out of a very fine point, but this method is messy.
Thanks Dan. Never thought about the ground plane issue. Hopefully that saves me from trying to overheat boards in the future
 
These are the way to go... I find that anything soldered to the ground plane is the problem. Did you notice that one lead of your cap moved easier than the other? I had this problem yesterday with a power supply cap on a board I'm working on... The cap was fairly easy to take out (caps are easy to remove because the leads are so close together, you can heat both leads at the same time with a chisel tip iron) but clearing one of the holes (ground plane) was nearly impossible to do. Wick won't do it and a solder sucker won't either. What does work is those SS fine point desoldering tools but a 3rd hand is needed. Another thing that works well is compressed air coming out of a very fine point, but this method is messy.
What is the ground plane of the PCB?
 
Ok guys I did it!
I added some solder, put the PCB in the third hand, heated up the joints and jiggled the cap on the other side until it came out. Binned it and ordered a new part.
My cheap solder sucker, after much cajoling, finally cleared both holes.

Thanks a lot to everybody who helped me out, you guys rock.
See you in my next post when the pedal doesn't work for other reasons :)
 
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