Testing for cold solder joints?

[BAM]

How can I check for cold solder joints? Thanks in advance

[Mark F]

One check is a visual check.Cold solder joints sometimes have a dull & sometimes whitish look. You can also use your ohmeter & check for intermittency, is that even a word? It is easier to just reheat any joint that appears suspect.

[niftydog]

eyes.  :shock:

Solder joints must be shiny and smooth. They should also have a concave shape - not convex. The entire pad surface should be covered with solder.

Using a meter may not help you at all - however it's useful to check for continuity where it is supposed to be as a general trouble shooting step. Also, cold solder joints often are fine to begin with but deteriorate over time.

[petemoore]

Let the MetalZ heat.
 Use very small amounts of solder to 'bridge the heat from the heat through the metals, you can tell when the least likely to heat [farthest away or connected to large thermal mass object] surface is heated enough by how fast it takes it to melt the solder.
 You can use the cool solder to cool surfaces you melt it on :cry: / :lol: .
 Enough solder is covering the 'avalalable surfaces', as close to the joint as possible, a little more provides structural integrity. I'ts easy to use too much.
 Not adding solder and continuing to add heat for the first 7/8ths second or so after. Whatever...I haven't had too much overheating problems. You can probably experiment with a little too much heat withought a big mess. Might weaken the pad a little, I've had Iron tips hook in and bake for like 6 extra seconds, and if I could finally retrieve it without blurbing a bridge to an adjacent already pretty heated soldered pad and ruin everything...I had no problems.
 Anyway point being you can just work with it on junk or what and see that after everything actually gets hot enough, not much else takes place. The solder kind of 'grabs', then settles as the heat gets everything, then doesn't do much unless you try to move it.

[bwanasonic]

eyes.  :shock:

At my age, I like to augment these with a studly magnifying loupe. Of course, when in doubt - reheat.

Kerry M

[petemoore]

Nice piece of glass and a close in light never hurt 'minutae' inspection results. I have one under a high intensity 60w quartz bulb in a gooseneck reading lamp, the glass is in a third hand setup. A second light from another angle is nice.
 I have a huge glass, with a circular light surrounding it, haven't even whipped the 3' bench mount device out yet.