Pad came off of PCB - Page 1
Forum section: electronics / beginners

author: MuTeD
author_rank: Contributor
timestamp: December 15, 2014, 07:20:27 pm
content: I just ripped off a pad from a small component (BLE113). The pads are 2mm by 0.5mm and 0.8mm pitch. Is it possible to try and solder this back on (I still have the pad) or would this just be a waste of time? Thanks in advance!

author: wraper
author_rank: Unknown
timestamp: December 15, 2014, 07:26:25 pm
content: Just take a piece of thin wire and use it instead.

author: MuTeD
author_rank: Contributor
timestamp: December 15, 2014, 07:49:40 pm
content: But what do I attach it too? I was using UTP cable to breakout the pads, but now it seems like i would have to solder it onto the solder mask (which seems nearly impossible).

author: Refrigerator
author_rank: Super Contributor
timestamp: December 15, 2014, 07:56:05 pm
content: Scrape some of that solder mask off and solder a thin piece of wire, i hope you're not using an automotive soldering iron.

author: pickle9000
author_rank: Super Contributor
timestamp: December 15, 2014, 07:56:29 pm
content: Can you put a couple holes in the pcb near the point? If so thread some wire through the holes, twist tight and solder to the broken trace. A drop of epoxy on the lead (between the two holes and solder joint) will act as a strain relief.

author: wraper
author_rank: Unknown
timestamp: December 15, 2014, 08:17:14 pm
content: Quote from: pickle9000 on December 15, 2014, 07:56:29 pmWTF that for? just soldering wire to trace cleaned from solder mask would be no worse without drilling shit out of the board. If any concerns, put a drop of RTV silicone on top.

author: MuTeD
author_rank: Contributor
timestamp: December 15, 2014, 08:42:00 pm
content: Quote from: Refrigerator on December 15, 2014, 07:56:05 pmok so basically just scrape off the solder mask where the pad was, attach wire to it? And I'm using a Hakko FX888D with a 1.8mm chisel.

author: IconicPCB
author_rank: Super Contributor
timestamp: December 15, 2014, 09:47:55 pm
content: Alternatively trace the copper and solder the wire elsewhere in a more suitable position

author: ptricks
author_rank: Frequent Contributor
timestamp: December 15, 2014, 11:15:35 pm
content: Unless you absolutely need the pad, use some wire:Take some AWG 30 wire ,strip the end, using cyanoacrylate (super glue) , glue the insulation covered wire to the board leaving about 1 inch of the stripped end free.After the glue has dried , solder the wire to end of the trace. If you don't glue the wire first the connection is so weak that it will likely break free if you move the wire. Some people use tape instead of glue, but I like the glue best.

author: wraper
author_rank: Unknown
timestamp: December 15, 2014, 11:43:12 pm
content: Quote from: ptricks on December 15, 2014, 11:15:35 pmNot a good idea because of 2 reasons: 1. cyanoacrylate glue is conductive, 2 if you heat it and some fumes gets in your eyes/nose, you'll regret it for sure.

author: hamdi.tn
author_rank: Frequent Contributor
timestamp: December 15, 2014, 11:52:26 pm
content: i use super glue all the time to fix wires in prototype board never had a problem with it being conductive , and yes your eyes will burn as hell if fumes get in it careful

author: ptricks
author_rank: Frequent Contributor
timestamp: December 15, 2014, 11:58:08 pm
content: Quote from: wraper on December 15, 2014, 11:43:12 pmThe glue that you find in most stores is not conductive and actually a pretty good insulator.You will not be heating the part that is glued, glue should be on the insulation , not the end.

author: 128er
author_rank: Regular Contributor
timestamp: December 16, 2014, 12:06:24 am
content: Had that problem with lifted pads a couple of times before. If it's just the pad that is lifted, then I prefer my fiberglass pen to scratch some soldermask off, a skalpell would be fine, too. But in my opinion you can work more exact with a fiberglass pen. After that, I often use one strand of a flexible wire - or what is available at the moment - to bridge the gap.Or as IconicPCB has mentioned, follow the track and find a location to solder a wire to some point.

author: wraper
author_rank: Unknown
timestamp: December 16, 2014, 12:17:32 am
content: Quote from: ptricks on December 15, 2014, 11:58:08 pmThen measure it. None of cyanoacrylate was not conductive as much as I tested. Right now took glue I have and measured drop of it. I got about 20 Mohm resistance.

author: 128er
author_rank: Regular Contributor
timestamp: December 16, 2014, 01:29:27 am
content: Quote from: wraper on December 16, 2014, 12:17:32 amI confirm that . . . if it's wet.If it's dryed, even my 500V insulation tester did not measure anything. Or did I miss something?