burned and liftef PCB tracks repair. - Page 1
Forum section: electronics / repair

author: knifesk
author_rank: Newbie
timestamp: April 18, 2013, 04:41:14 am
content: Hi everyone! I've subscribed to the YT channel yesterday! It's really nice and full of knowledge! I'm a hobbiest solderer myself.. never designed a PCB or something like that, but I've changed some caps over time and I'm really interested in electronics (as hobby of course)So, cut to the point! I would like to suggest a video for the blog that maybe helps me to solve a problem that I currently have.I've purchased a used AsRock motherboard.. according to the seller the board was perfectly functional, the only issue was that the PCI-E socket clip (the one that locks the VGA to the socket) was broken.. As I had no plan to use anything but the integrated graphics I didn't mind and proceeded with the deal (the board was very very cheap). When it arrived home, I've noticed that a track was completely burned and lifted from the board, and a really bad solder "patch" was applied. As the track was lifted off like 3cm long I've made the decision to cut it out and replace it with a single copper thread wire.. like UTP cable internal wires. I've soldered the cable, isolated both solder points to prevent shorts and turned it on... It works, but is a really really nasty fix. So, the idea was that Dave could make a video about this topic. What do you think?I don't have pictures right now, but I've found this picture that has a similar problem.. the only thing is that in my case the track is like 2mm wide and burned distance is like 30mm straight (no corners).

author: David_AVD
author_rank: Super Contributor
timestamp: April 18, 2013, 07:59:10 am
content: I've repaired boards before with appropriately sized tinned copper wire. You do need to carefully remove all of the lifting / affected track and tin each track ends a few mm.I'll usually use a sharp blade to carefully cut across the track a bit before the damaged part, then peel the damaged bit off. This makes a neater cut and helps stop the end from lifting in the future.If possible I'll run the new wire all the way from one pad to the other (bypass more than just the actual burnt bit) so there's more area to solder to and reduce the likelihood of more damage.

author: mariush
author_rank: Super Contributor
timestamp: April 18, 2013, 08:35:57 am
content: Here's a couple of videos that show how to fix thatPACE Rework and Repair of Electronics Lesson 6 - "Damage Repair"

author: Joules
author_rank: Contributor
timestamp: April 18, 2013, 10:18:21 am
content: Love the advert at the end, we are having all our 6 layer board techs fitted with catheters. Should boost company profit and keep the water bills down

author: David_AVD
author_rank: Super Contributor
timestamp: April 18, 2013, 11:18:37 am
content: Well done. I've done similar repairs to a TV before. It's nice when the tracks are relatively large and can accept a good chunky wire bridge.

author: Smokey
author_rank: Super Contributor
timestamp: April 18, 2013, 07:30:08 pm
content: Nice. Especially that SA repair. That's hardcore rejoining a cracked PCB from one side to the other.I had an IGBT blow up and arc to the PCB once, burning a hole the size of a dime (~18mm) through 3 of the 6 layers. It was one of a small batch of prototypes so I had to fix it. I ended up scraping away the burned FR4 and bridging parallel 6mil traces across the hole on an inner layer. Then I epoxied that over and repaired the power trace on the outer layer over the epoxy. That was a job and a half. I think that board is still going strong and all the rework was on the bottom side so unless you took it off the heatsink you would never know it had it's chest cracked and underwent a quadruple trace bypass procedure. Now if only I could convince someone to pay me chest surgeon salary I'll be all set.

author: justanothercanuck
author_rank: Frequent Contributor
timestamp: May 04, 2013, 07:37:07 pm
content: I've seen and done fixes like this before...What I would do is glue down the pieces that are floating, don't worry about trimming them or anything, just so long as they don't touch anything else... Then I would scrape the solder mask off near the edge connector (above the connector, but below the burnout) and solder two wires from the edge connector to the two solder points on the other side of the burnout. Then to top it all off, glue the wires down so they don't get ripped off the board. It's an ugly looking job, but every bodge job looks ugly.Good luck