R259 came ALL the way off- Now What?!!

[rolandska2]

Hi,

After all the ECM's going on lately I decided to put on a dig. lock(my 1st). When I pulled up R259 the solder joint came up as well. It looks to me like the trace goes directly to the TSOP... Am I F**cked or what? Is my 4900 now totaly useless? Is there a way to put a joint back in there? Please, could somebody with a little experience help me out please? I know you all are busy lately but I always search 1st and ask as a last resort... My thanks to those who give a shit!

R

[Project2501]

R259 was supposed to be completely removed. I'm not sure what you mean when you say the solder joint came up as well. Ther'es just a couple little solder pads under R259. One side of the trace you severed by removing R259 is WE1 and the other is WE0. Are you saying you did some physical damage to the PCB? It shouldn't really matter that much so long as you can still solder WE0 to the left side of the gap you made when you removed R259.

[rolandska2]

Allright I did some more searching and found my answer in a totaly unrelated thread. Apparently if you pull a pad or if a pad is missing you can just use a razor to clear the top of the trace and solder(very carefully) to the trace itself. Use the razor and carefully scrape the trace until you can see the wire(don't sever any other traces) and use a SMALL amount of solder to connect to the trace. I don't know if this will hold good enough but I don't have another choice so bombs away! Thanks anyway to those who help- the rest of us would be lost W/ out you!

R

[rolandska2]

Hey thanks for the reply! Yeah I DID pull up the little pads you refer to--Do I have the right idea to fix?? What is the PCB-for future reference?

R

[Smurftoon]

PCB =Printed Circuit Board

[Project2501]

You can solder directly to that trace and expect it to hold. Solder is actually pretty darn strong when it's been melted and cooled. In order to have pulled those pads up you had to put way too much heat to the board. Maybe you should get a dead anything with a PCB and practice removing and reinstalling parts off the board to refine your technique a bit.

[t160hq]

Might have been too little heat and too much physical force on the part as well.

You really need to heat both sides on a surface mount resistor to remove it. But in the real world of the hobbiest this is not going to happen. So try to keep the iron on the top edge or little metal end cap of the resistor (not where it meets the PCB trace). Then heat it till you see the solder start to melt on both sides. (The heat will transfer across the resistor itself to the other side) Then move the resistor out (Gently while still holding the iron on it) with a dental pick or similar device.

My favorite method is to heat one side till it melts then move to the other side and follow the instructions above. The shorter the time the iron is on it the less likely you'll get trace damage.

The trick is to keep as much of the heat as possiable on the resistor rather then the PCB traces.

t160hq

[skinerd]

You can solder directly to that trace and expect it to hold. Solder is actually pretty darn strong when it's been melted and cooled. In order to have pulled those pads up you had to put way too much heat to the board. Maybe you should get a dead anything with a PCB and practice removing and reinstalling parts off the board to refine your technique a bit.

Most traces can be followed to a point where soldering is much easier than soldering to the trace itself, not always the case but usually is.

[Westy]

rolandska2

The same thing happened to me. I scraped off the covering on the trace, and soldered the wire to it. I then mixed up some 5 min epoxy and placed some on the solder joint, anchoring it to the board to give it some strength. It has worked well and is more secure than if it had been soldered to the resistor pad.

-------
Westy

[Project2501]

I recomend that the only 'glue' you put on your PCB is a good rosin core solder. That epoxy won't ever come off and it can't be reworked.

[Westy]

That's not been my experience working with epoxy, but some have more patients than others.

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Westy