Tantalum Capacitor desoldering- safety concerns

[Alex_Santos]

Dear members

I have the TS100 soldering iron, not a tweezer type and some tantalum capacitors that I need to remove.

Considering the tools I have, desoldering braid, flux and the iron but are there safety concerns to account for? Namely the tantalums blowing up? I will use glasses but I wanted to know if this is legitimate concern or an event that happens with very little frequency.

Kind regards
—Alex

[stj]

Re: Tantalum Capacitor desoldering- safety concerns

they dont blow up, they are just a lump of tantalum in a plastic box.
removing them with an iron wont be easy though, the contact wraps under the cap body.

[R_J]

Re: Tantalum Capacitor desoldering- safety concerns

You will be fine, the capacitor will not blow up. A tantalum cap can blow if it becomes shorted when voltage is applied to it, it wont blow while soldering or desoldering
Use extra flux if you can, that will help the old solder flow when heated, and be careful to not put too much force if you are lifting it so you don't lift the trace with it.

[Alex_Santos]

Re: Tantalum Capacitor desoldering- safety concerns

Thanks stj and R_J. I desolder my first tantalum. What appears to be 10x harder are the small electrolytic caps, man are they ever tough to remove. I avoid bending or rocking the cap, maybe that's why but I can't risk damaging the pads.

Thanks again!

[stj]

Re: Tantalum Capacitor desoldering- safety concerns

smd electrolytics are a bastard, there are a few methods used - each has pro's & cons.
i like to twist them to break the legs - then desolder the legs
sometimes the legs just pull away from the pads as you twist.

[Alex_Santos]

Re: Tantalum Capacitor desoldering- safety concerns

Some folks really are against this as pads might come off as a result.

Maybe I just have to purchase desoldering iron tweezers, they can come handy in these cases, at least for me.

Thanks again!

[mariushm]

Re: Tantalum Capacitor desoldering- safety concerns

I find the easiest technique is to just add a blob of solder on each pad / leg then with the iron tip hot, alternate between the ends for a few seconds at a time to keep both blobs hot and gently push on the capacitor with something (a toothpick, a tiny screwdriver, a dentist pick, a spudger, whatever)

Afterwards you can use some solder wick or whatever you want to clean the pads.

[stj]

Re: Tantalum Capacitor desoldering- safety concerns

alternating can also lift pads, there is no 100% safe method other than hot air.
that brings it's own problems, you have to puncture the can first or it can explode!

and obviously it cant be close to any other electrolytics or plastic such as connectors.

[Alex_Santos]

Re: Tantalum Capacitor desoldering- safety concerns

Guys, I figure out a method.

I put an ample amount of flux and then soak fresh solder onto the pads. Then I heat up with 400°C which is what I found works. I alternate between sides with the iron while gripping the cap with small players. As I draw heat to each side I gently wiggle the cap until it begins to lift on one side. If needed I add more solder as this creates a nice heat reservoir.

After two minutes the cap is off, I clean up the excess solder with a copper braid and then clean with isopropyl alcohol.

This appears to work quite well for me and so far I removed about 8 caps, 2 wants and 6 electrolytic.

I appreciate everyone's advice and support as this is my first attempts on a test logic board that got destroyed beyond economical repair by a leaked battery.

Thanks everyone.
—Alex

[Alex_Santos]

Re: Tantalum Capacitor desoldering- safety concerns

Just a quick follow-up on my process.

1) add a liberal amount of isopropyl alcohol around the cap
2) add flux to both the + and - side of the cap
3) With the iron already hot, contact the terminal and add a good amount of solder to both sides
4) Alternate back and forth between each side while gently rocking or lifting the cap. This relies on my sense of feel but I maintain a gentle tug while alternating.

This has proved the quickest method for me. I have pulled 20+ caps since my last post thanks to all of you who volunteered your strategies/recommendations. I couldn't have done it without your advice.

After spending countless hours watch PACE videos, EVBlog videos I finally feel like I touched down, touching metal for the first time and the satisfaction is immense.

Thank you all for helping me along this new journey. I love electronics and I am in my diapers still but everyone's help has been critical and supportive.

Best regards
—Alex