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de-capping (prior to re-capping)?

bugbear

pfm Member
Assuming I don't have a fancy solder rework station (because I don't :)), what's the "approved" way to desolder a radial capacitor?

Removing a resistor, or axial capacitor, is super easy because you can easily desolder one end, and lift it clear, then do the other end.

But a radial cap won't come out that way.

(I guess small signal transistors are even worse).

Tips, links, videos all welcome.
 
Place a piece of desoldering wick/solid copper wire so that it spans both pads, add solder and both pads will melt at the same time. Adding a bit of fresh solder to the pads helps the old solder melt quicker.
 
Cut down the middle of the can with fat sidecutters, then desolder the legs individually as you would other components as you described. You can also cut the can off leaving a couple of mm at the bottom and then pic that off, just leaving the legs. Very destructive, but you didn't want the old car anyway.
 
If the pin spacing is narrow then use a wide nib iron and heat both pads at the same time, if wide spaced then use tilt method.
 
Or use two soldering irons. Hold them like chopsticks with one hand while pulling the capacitor with the other.
 
Assuming I don't have a fancy solder rework station (because I don't :)), what's the "approved" way to desolder a radial capacitor?

Removing a resistor, or axial capacitor, is super easy because you can easily desolder one end, and lift it clear, then do the other end.

But a radial cap won't come out that way.

(I guess small signal transistors are even worse).

Tips, links, videos all welcome.

Most of the above will do the trick - I use the technique for radials described by mansr in the first reply ;)

But just to add that it's worth removing as much of the old solder as you can before removing anything. A solder sucker and wick work well for this.
One problem I get sometimes if I don't take the time to do this is that the hole floods shut with solder as I pull the component wire.
Can be a risky business trying to free it afterwards with a chance of damaging the track (which I have done in the past ...)

Another key tool is long-nose pliers ... saves burnt fingers ;)
 
The ultimate rebuttal of "intelligent design" is the fact that we don`t have three hands for this kind of stuff.
 
The ultimate rebuttal of "intelligent design" is the fact that we don`t have three hands for this kind of stuff.

I used to build lasers and laser amplifiers and I always felt that a short arm coming from the middle of the forehead would be a big advantage, especially for holding an infrared viewer - but it would look a wee bit silly :)
 
Hot air can be good too if you have a hot air gun with a fine end. These are amazing for the money when they are in stock:

https://hobbyking.com/en_us/portable-digital-heat-gun-eu-version.html?___store=en_us

Available in 110 and 230v but supplies are sporadic. Variable temperature and airflow with a fine tip. I find it good for heatshrink desoldering chips and multi lead components and soldering small SMT stuff with the pads under the chip. Very handy, steinhel(sp) do a proper industrial version for about £250 from memory.
 
But just to add that it's worth removing as much of the old solder as you can before removing anything. A solder sucker and wick work well for this.
With plated through holes, removing too much solder can make it difficult to apply enough heat quickly.

One problem I get sometimes if I don't take the time to do this is that the hole floods shut with solder as I pull the component wire.
Can be a risky business trying to free it afterwards with a chance of damaging the track (which I have done in the past ...)
Iron on one side, solder sucker on the other tends to work.
 
Buy this lovely Japanese Engineer brand desoldering pump. Just trust me. It is brilliant. It has a remarkably strong suction and because the end is silicone tubing you can hold the iron right against it without melting or damaging it. I also have a proper Hakko FR301 desoldering gun (crazy expensive now post Brexit (I paid £300, and that felt like a lot!)) but if I’m just doing a couple of caps, resistors etc I use the little Engineer sucker. It really is remarkably good. Amusing to see just how far they’ve spread around the YouTube vintage computer and video game community, nearly everyone uses one now!
 
This site contains affiliate links for which pink fish media may be compensated.
Use paste flux, the none clean up type, but do clean it afterwards. Mansr's rocking method is my preferred version. But if there's space I like to use side cutters to clip the can off ASAP as it just acts as a huge heatsink, more an issue with big psu caps than small voltage/ capacitance types.

Simon, currently removing 16 caps and 60 transistors from a bad diy build.
 
Be careful with that one. It can easily poke you in the eye with considerable force. I prefer the ones with a guard to prevent this.

I once saw someone at Broadcasting House smash the bulb in his benchlight with a similar device.
 
To clear holes of solder, flood them with fresh solder, then vac pump or braid them off. For stuff with a ground plain that is wicking all your heat away preventing you clearing the hole, I heat the pad with an iron (from the ground side) then poke through a bit of 0.5mm stainless wire. The solder will not stick the the stainless and you don't risk damage to the through hole plating. 0.6mm pcb drill is a last resort to clear holes, multi layer pcbs with mid layer ground plains are the worst.
 
To clear holes of solder, flood them with fresh solder, then vac pump or braid them off. For stuff with a ground plain that is wicking all your heat away preventing you clearing the hole, I heat the pad with an iron (from the ground side) then poke through a bit of 0.5mm stainless wire. The solder will not stick the the stainless and you don't risk damage to the through hole plating. 0.6mm pcb drill is a last resort to clear holes, multi layer pcbs with mid layer ground plains are the worst.

I have stainless dressmaking pins reserved for the occasion ;)
 


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