[BatCaveTrep]

Has anyone successfully repaired one? I have taken one apart and it is more electrical than mechanical. The only mechanical part controls the clock's arms, so my theory is the problem lies in the circuit. Possibly these solder points, that controls the motor that is connected to the arm's gears. Any insight?

[cdmccul]

I'd re-heat any large pin connectors with a soldering iron and a little flux. You probably don't need any solder to go with it. Reheat the solder till it gets shiny, then remove the iron and don't bump the board till it frosts over slowly. Then move to the next pin. I'll be posting a how-to soon on a gauge cluster repair.

[BatCaveTrep]

You have already lost me. The only soldering I ever do involves adding solder, so I have no clue about flux and removing iron. (new to the world of solder) Is my assumption correct that the problem, with the clock not working, could be in those solder points? What is the brown stuff? It also looks like the solder points are touching, so I may just redo it.

[FREE93CORDE]

the "brown stuff" is flux material used when soldering. you can get solder wick or a solder sucker at radio shack. solder wick looks like braided copper. the sucker is tool you cock a mechanical plunger then press on a lever/or button which then creates a vacuum making it suck up the hot solder

[CaptainMorgan]

I always just throw away broken dash clocks. I've got a whole box of them.

I should take a run at repairing the next one, if it really is just solder joints that would be a piece of cake.

[BatCaveTrep]

I figured I would look into before spending $30+ on a working one. The board and all solder points look good except for those five. What is the purpose of flux? I've never used it.

[cdmccul]

Flux is a cleaner used to eat away any contamination or corrosion, so that when you apply solder, it sticks really well. The brown on the current solder is not likely flux, but may be. I'd clean it with rubbing alcohol first, and then make sure any fibers from the cleaning cloth are removed.

I was distracted a bit with my last post about how to fix - let me try to clarify in my next post here.

[cdmccul]

So - the iron I talked about was the soldering iron.

I use one of these:


These are most popular:


You could un-solder, but I personally wouldn't worry about that.

Here is a solder sucker being used (the green thing in the person's right hand):


and here is a de-soldering wick:


Sometimes a solder sucker looks more like an infant snot sucker, but I've never used that kind.

SO - how to fix...

After cleaning, heat your iron up. Apply a dab of flux to the area of the board you are going to be working with - a small dab on each pin, for example:


I apply flux with a paper clip or toothpick.

Take your hot iron, and place it against the first pin. Hold it there, and the flux will melt and thin out, and then bubble - and then the solder will begin to melt. Don't hold your face over the smoke that comes up... I've never been harmed (that I know of!) by it, but it isn't the most pleasant to inhale.

Watch the solder get hot and liquefy, it will get shiny, then remove the soldering iron from the pin. You don't want to overheat it (melt the plastic that forms the socket), but you don't want the joint to be too cold either. As the solder cools, it will frost over in appearance. Do not shake or wiggle the board while it cools. When the first pin is cool (won't take but a few seconds), move to the next pin.

When you are all done, wash the board again with rubbing alcohol and check your work.

Under magnification, you may be able to see the cracked solder joint.

[300maximilien]

I'll sell you one for $20 shipped if interested...pm me

[CaptainMorgan]

Nice little how to.

Solder fumes are really bad for you, but most people don't really bother to worry about it. I wear a respirator all the time when I solder because of the high volumes I've done at work. Most people even there just put a fan on their work so the fumes don't come up into their face.

I solder with one of these at home.

[BatCaveTrep]

Does the clock have the blank white face or does it show the number marks? Would prefer one with the markings, but no wings. I will let you know for sure in a few days. I would like to try and find why the clock died to begin with.

[cdmccul]

Very good point - yes, you should do something to mitigate the fumes being inhaled. In the very least, the lead in the solder itself is probably bad enough (non-plumbing solder), not to mention contaminates on the board, chemicals in the flux, etc. A small fan would probably be best, but I've used some irons that aren't powerful enough to recover from a strong air current(!). I end up taking a deep breath, then exhale slowly while soldering - but I don't generally solder for more than one or two joints or contacts at time.

One strange thing I noticed about solder smoke - it ALWAYS drifts to my face... it is such light smoke, I think it follows the heat of my head, as my head forms a draft of its own above me, and the smoke follows it. If I start out over the work, and then move away, the smoke follows me... BUT, if I start exhaling and blowing gently towards the work, and don't start with my face over it, the smoke will drift away very nicely.

[CaptainMorgan]

Yeah when you do a couple at a time you don't really need to worry, but I've sat and done hundreds in a row where my face has to be right on top of it.

If I had an iron that couldn't handle a gentle breeze I would throw it away .

I fought for way too long at home using shitty off the shelf irons and eventually got fed up. On car wiring half the time they couldn't generate enough heat to get the wire to melt the solder. Now I use something that's the real deal always and it was well worth the investment. Temperature control for soldering helps so much. I can go from heavy wires down to circuit board joins with always having just enough heat to make it easy.

Here is an excerpt from a MSDS data sheet for a random rosin core solder I looked at.

"Prolonged overexposure to lead can result in systemic poisoning with symptoms of metallic taste, anemia, insomnia, weakness, constipation, abdominal pain, gastrointestinal disorders, joint and muscle pain, and muscular weakness, and may cause damage to the blood-forming organs, kidneys, nervous and reproductive systems. Damage may include reduced fertility in both men and women, damage to the fetus of exposed pregnant women, anemia, muscular weakness and kidney dysfunction."

"NORMAL HANDLING:
Use of approved respirators is required for applications where adequate ventilation cannot be provided. Activities which generate dust or fume should be avoided. When melted, the temperature should be kept as low as possible."

[BatCaveTrep]

That soldering setup looks nice. What model is that? I have that $10 Radio Shack iron () and some little handheld red sucker, which is pointless. I have never needed a decent iron, since the RS cheap one does fine for small quick jobs. Anyways I hooked up the power and started probing around, with a multimeter, and never found a power reading, so the board may be damaged. I figured I would have had a reading off one of those 5 pins.

[CaptainMorgan]

That's a weller WES51 station. They have both analog and digital versions but I've grown accustomed to the analog versions at work so I saw no need to get a digital for home. I picked it up for about 80 bucks a while back.