thanks

[Sniper82]

I have something that has been damaged do to a screw drive smacking the PCB and going through a trace(not sure if the trace is completely cut in half). I was curious what is the best and easiest way to remove some of the insulation off the trace so that I can try to repair it using a conductive pen.

Suggestions?

 

[CTho9305]

I sand off the colored top layer cause that insulates. This exposes the actual trace. Then I solder carefully

 

[Sniper82]

sounds good

Well I will try with the pen first but if it doesnt work I have some 30gauge wire that should do the trick. The thing is dead so I don't think lifting the trace will hurt any worse .

Thanks for the info and if someone has any other suggestions please post them.

 

[Evadman]

they also sell trace repair kits that are basicly little pieces of flat copper in common trace widths. I picked some up from a hot deal a while go. game with the tools and everything, all for free Samples rule!

 

[Peter]

On a standard 4-layer board there's a good chance you didn't break anything in the inner layers. Scrape the paint off, and solder with a steady hand, under a magnifying glass with good lighting.

 

[blahblah99]

If it's a 4-layer board and the screw fell onto the traces while the board was still powered, it might damage some internal traces, but if it wasn't powered, you're good to go to repair it.

I usually just scrape off the solder mask with an exacto knife to expose the copper and then use VERY FINE wire for signal traces, or regular 22gauge wire for thicker traces.

 

[dkozloski]

You might also be able to jumper around the damaged area by connecting to the pads for circuit components on each side of the break using a fine insulated wire like "wire wrap".

 

[Sniper82]

"You might also be able to jumper around the damaged area by connecting to the pads for circuit components on each side of the break using a fine insulated wire like "wire wrap". "

I got to thinking that earlier but that is a good point. I will attempt this before doing anything else.

 

[dkozloski]

You can't hurt anything by trying and it is not unusual to see mods made to circuit boards with this technique.

 

[Peter]

Originally posted by: ^Sniper^
"You might also be able to jumper around the damaged area by connecting to the pads for circuit components on each side of the break using a fine insulated wire like "wire wrap". "

I got to thinking that earlier but that is a good point. I will attempt this before doing anything else.

No don't. You're making an antenna.

 

[dkozloski]

Peter, it depends on what signal the trace carries. Beyond that, so what if it does radiate as long as it works. If it doesn't work try another technique.

 

[Sniper82]

"No don't. You're making an antenna."

Whats that do?

 

[dkozloski]

If the trace you are repairing has a high frequency square wave or some other similar siganal on it, the wire you add may be of such a length that it may resonate with this signal and cause it to be radiated or transmitted in the immediate area, like an antenna. This may cause some very low-level interference in your TV or radio reception. Put the cover back on your case and the problem is eliminated. This is not an issue to lose sleep over.

 

[CTho9305]

The trace goes to a pin used as a reference for Vcore or something like that. A121 IIRC.

 

[Peter]

Originally posted by: dkozloski
If the trace you are repairing has a high frequency square wave or some other similar siganal on it, the wire you add may be of such a length that it may resonate with this signal and cause it to be radiated or transmitted in the immediate area, like an antenna. This may cause some very low-level interference in your TV or radio reception. Put the cover back on your case and the problem is eliminated. This is not an issue to lose sleep over.

The real problem is that the signal wire itself PICKS UP all the radiation inside the computer, which is not at all what you want.

 

[heliomphalodon]

Originally posted by: Peter
The real problem is that the signal wire itself PICKS UP all the radiation inside the computer, which is not at all what you want.

Why would the wire pick up radiation any more than the original trace would?

 

[AbsolutDealage]

Why would the wire pick up radiation any more than the original trace would?

Because the trace is shorter, the connections are not leaky, the entire trace is sealed, etc. Also, a professionally designed board is layed out in such a way that nearly all interference cancels out, or is shielded by a ground wire.

 

[dkozloski]

Give it a try, no guts no glory, the proof of the pudding is in the eating, and a whole host of other sayings apply. You won't know unless you try it.