Friday, April 6, 2012

Desoldering SMD Parts - No Fancy Tools

So this post is in,well yeah,de-soldering SMD parts without using any special tools or chemicals(ChipQuik looks like TV magic!)
I had a non-working Cypress PSoC3 First Touch Kit (btw,dont ever buy one.I'll do a review sometime soon where I'll tell you why) from which I wanted to remove the 12pin 2mm pitch(when did 2.54 become an unlucky number?) SMD header intended for their CyFi wireless modules made by Artaflex.

The SMD header in question.
 So yeah,Since the kit was badly damaged(too fragile,they are.) I thought it fit to take off this weird header,and use it for my PSoC3 Wireless development board(future project).

As far as soldering equipment goes,I own a cheap 25W iron,and some flux cored solder wire of local make,I think 1mm or so in diameter.Yeah,that's it.

So here is a cool trick that worked.I don't know if its already out there,but I'm documenting it here anyway.

1.Flood the pins with solder,on both sides
solder flooded pins
2.Add enough solder so that each pin is part of this huge glob,on either side.In this case,I removed those anchors(on either edge of the part) using a bit of stiff wire to pry them up while keeping their solder molten with my iron.Then heres the part that needs to be done with some deftness.
keep running your iron's tip along the sides of the part,keeping both solder globs molten long enough to allow you to take off the part with tweezers (if you have them),or you could hold the board at some steep angle,so that the molten solder on both sides cant hold the part against gravity,and it slides off.Thats what I did here.

Off with you head(er)!

In this case I had planted the board onto a breadboard,so I could hold my work easily,and then held that almost vertical,so that the SMD header came off easy when the globs were molten.

A good part about this method is that you leave most of that excess solder on the board,not the part.So thats less of cleaning the part's pins.Thats a big concern if its some close pitch TQFP or something.

3.After a bit of cleaning with some IPA from a friend(Thanks!),heres what the end result is
Tada!

Easy :-)

2 comments:

  1. Great Post!
    But One of the easiest ways to desolder SMD is to use hot air. And it seems like you are working with some really hardcore SMD components. A hot air workstation will save you a lot of time/components! I recently got a hot air rework station for like 3K here in mumbai!

    ReplyDelete
  2. Hey Murali,
    Thanks for the compliment :-)

    Yes,a hot-air station would be the best way to go.An interesting point you made about the price,3000 sounds good for one.I'll see if I can get my hands on one ;-P

    ReplyDelete