Removing surface mount capacitors

Discussion in 'Modding and Hacking - Consoles and Electronics' started by phillip, Jun 24, 2018.

  1. phillip

    phillip Active Member

    Joined:
    Dec 13, 2015
    Messages:
    39
    Likes Received:
    8
    Just thought I'd share a time-saving tip for replacing capacitors. Experienced repair techs need not apply.

    I recapped my Sega Saturn today. It had 27 surface mounted capacitors. I watched a few youtube videos on ways to remove them and tried something that some of you are undoubtedly going to cringe at.

    In short, rather than desoldering the capacitors, you can simply use a pair of pliers to gently grab the capacitors and twist them off. The key here is to twist, not pull. I was able to do this with all 27 caps and I didn't lift a single trace or pad, nor run into any complications. Before the repair, no video. After recapping the Saturn, video on the first boot.

    The obvious risk here is that if you have a particularly fragile board, you run the risk of lifting a pad or trace. Use good judgement. All I can say from my experience is that this method worked perfectly and saved me a ton of time.

    Youtube link for reference:

    Best of luck!
     
    Nully likes this.
  2. Nully

    Nully Enthusiastic Member

    Joined:
    Nov 23, 2010
    Messages:
    545
    Likes Received:
    36
    Yep, that's the trick for sure.
     
  3. Sp33dFr34k

    Sp33dFr34k Spirited Member

    Joined:
    Jul 13, 2015
    Messages:
    135
    Likes Received:
    23
    Damn, I wouldn't have the guts to do this on more expensive hardware than a Saturn.

    I'd use one of these:

    [​IMG]
     
    -=FamilyGuy=- likes this.
  4. Taijigamer2

    Taijigamer2 Gutsy Member

    Joined:
    Jun 29, 2015
    Messages:
    425
    Likes Received:
    150
    I think I'll stick to desoldering the old fashion way.
     
  5. takeshi385

    takeshi385 Mojarra Frita Bandit

    Joined:
    Mar 29, 2011
    Messages:
    1,829
    Likes Received:
    141
    Hot air and tweezers.
     
  6. 8bitplus

    8bitplus Gutsy Member

    Joined:
    Feb 25, 2008
    Messages:
    434
    Likes Received:
    31
    The method in the video works fine... if the board is strong and the solder pads for the caps are not compromised by fluid leakage.
    If the console/computer is needing new caps, and they have leaked, the solder pads will be weakened and can result in the copper pad being torn off if you remove the caps like that.
    For any leaked caps NEVER twist or pull them off. First at least attempt to desolder the cap with something like the desoldering tweezers above, or a regular iron and tweekers.
    Hot air can also help, but I find the corrupted solder is hard to melt with air sometimes, and needs an iron and a touch or fresh solder+flux. I've also heard of caps exploding with hot air lol.
     
  7. 8bitplus

    8bitplus Gutsy Member

    Joined:
    Feb 25, 2008
    Messages:
    434
    Likes Received:
    31
    @phillip
    Your Saturn was probably in fine shape without changing the caps. I've never seen a Saturn needing new caps. Its not like a PC Engine DUO or GameGear where the caps all the the PLAGUE .
     
  8. Nully

    Nully Enthusiastic Member

    Joined:
    Nov 23, 2010
    Messages:
    545
    Likes Received:
    36
    Capacitors can definitely pop with hot air. Ask me how I found that out the day my first rework station arrived.

    Scared the crap out of me, now I wrap everything in aluminum tape/foil.
     
    Traace likes this.
  9. phillip

    phillip Active Member

    Joined:
    Dec 13, 2015
    Messages:
    39
    Likes Received:
    8
    As I said, my Saturn was outputting no video. Wouldn't call that "fine." About 4 of the capacitors had substantial corrosion beneath them. I don't recap consoles for fun. I was repairing it. According to my research online, more and more Saturns are needing cap replacements. It's not that uncommon, actually.
     
  10. Bad_Ad84

    Bad_Ad84 The Tick

    Joined:
    May 26, 2011
    Messages:
    8,237
    Likes Received:
    1,052
    All electrolytic capacitors have an finite life span. Saturn is about at that point and are most certainly starting to fail. Also, they don't need to leak to be faulty - they can equally dry out and give no visible signs.
     
  11. Jord4n313

    Jord4n313 Member

    Joined:
    Jun 27, 2017
    Messages:
    18
    Likes Received:
    1
    When you say pop or explode, what kind of explosion are we talking about? Like those pop snaps you throw at the ground? An M80? Enough to do damage to the board.....or your body? Just curious.
     
  12. Nully

    Nully Enthusiastic Member

    Joined:
    Nov 23, 2010
    Messages:
    545
    Likes Received:
    36
    More of a pop than an explosion and if I remember correctly, it shot something across the room. I was just desoldering a broken motherboard and testing limits etc with the new equipment I hadn't used before. You'll probably never have that happen unintentionally.
     
  13. Sp33dFr34k

    Sp33dFr34k Spirited Member

    Joined:
    Jul 13, 2015
    Messages:
    135
    Likes Received:
    23
    The same thing that happens when you switch the positive and negative leg of a cap when soldering it back on, guess how I found that out :D
     
    Taijigamer2 likes this.
  14. Bruktmoped

    Bruktmoped Rising Member

    Joined:
    Mar 16, 2016
    Messages:
    50
    Likes Received:
    10
    Ive tried most aproaches over the times. Twisting is a bad idea. You could be lucky, I have been many times too, but when you do damage a pad or two, its a huge job to repair. The tweezer thing works in many cases, but now, I only use hot air and kapton tape on select areas. And protective eyewear. :) It saves time in the long run. At least for me.
     
  15. -=FamilyGuy=-

    -=FamilyGuy=- Site Supporter 2049

    Joined:
    Mar 3, 2007
    Messages:
    2,816
    Likes Received:
    657
    This "technique" seems like the "field-medicine" version of desoldering...
    It's not that it doesn't work if you really need it, but it's not optimal if you can avoid it...

    Soldering tweezers are like 30$, if you're gonna desolder a good amount of caps, it's worth it. Or just use two soldering irons like two-handed chopsticks...
     
  16. CZroe

    CZroe Rising Member

    Joined:
    Jan 13, 2013
    Messages:
    69
    Likes Received:
    3
    GameTechUS uses flush cutters so that the caps rupture instead of the pads. I still don’t like it because it can spill electrolyte on the board if the cap wasn’t dry/leaked.
     
  17. acidtalk

    acidtalk Active Member

    Joined:
    Jan 18, 2014
    Messages:
    35
    Likes Received:
    4
    off topic but, how much did it cost you to recap the saturn ?
     
  18. Nully

    Nully Enthusiastic Member

    Joined:
    Nov 23, 2010
    Messages:
    545
    Likes Received:
    36

Share This Page