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Help with electonics repair. Need to fix an external HDD enclosure.

This topic can be found at:
https://sigforum.com/eve/forums/a/tpc/f/320601935/m/9160013684

October 30, 2021, 10:07 AM
ensigmatic
Help with electonics repair. Need to fix an external HDD enclosure.
quote:
Originally posted by sigcrazy7:
I’m not that interested in purchasing a new 1394 enclosure, being that FireWire is quite obsolete. Also, I’m getting tired of filling our landfill with crap ...

Agree.

I'll spend perhaps an inordinate amount of time and money saving something, if I can, before sending Yet Another Thing off to the landfill.

quote:
Originally posted by sigcrazy7:
As for testing it first, it’s swollen, and it costs less than a dollar. I’ll put the meter to it, ...

Unless your meter has a specific capacitor test mode you can really only test it for a dead short. Not having a dead short does not necessarily equate to good.

I wouldn't even bother. It's visibly swollen. I'd replace it. I'd replace them all while I was at it.

quote:
Originally posted by PHPaul:
I think it's more common for pads to be damaged by too LITTLE heat applied for too long a time. Folks use undersized irons for fear of damaging the board or components and wind up pressing too hard and spending too much time trying to get the solder to flow.

We were taught to go in hot and get out quickly.

That is certainly a valid point.

quote:
Originally posted by PHPaul:
Another factor is CLEAN! Clean tip on the iron, clean solder and clean the pad before trying to desolder. Oxidized solder is a pretty decent insulator.

True, but here's a little trick: Apply a touch of clean solder to the tip of the iron before attempting to de-solder. That will speed-up heat transfer to the existing soldered joint Smile

Same thing for soldering a fresh joint. A mistake soldering newbies make is applying solder to the iron or the iron/joint junction, whereas what you're supposed to do is apply the solder away from the tip of the iron. This ensures the entire joint is heated so the solder will flow throughout the joint. (Solder flows toward the heat source.)

But sometimes it can be difficult to get the heat to start transferring from the tip of the iron to the joint. Applying just a "dash" of fresh solder to the tip/joint junction to speed heat transfer can save insulation, PCB pads, components, what-have-you.



"America is at that awkward stage. It's too late to work within the system,,,, but too early to shoot the bastards." -- Claire Wolfe
"If we let things terrify us, life will not be worth living." -- Seneca the Younger, Roman Stoic philosopher
October 30, 2021, 10:16 AM
PHPaul
quote:
Originally posted by ensigmatic:

True, but here's a little trick: Apply a touch of clean solder to the tip of the iron before attempting to de-solder. That will speed-up heat transfer to the existing soldered joint Smile

Same thing for soldering a fresh joint. A mistake soldering newbies make is applying solder to the iron or the iron/joint junction, whereas what you're supposed to do is apply the solder away from the tip of the iron. This ensures the entire joint is heated so the solder will flow throughout the joint. (Solder flows toward the heat source.)

But sometimes it can be difficult to get the heat to start transferring from the tip of the iron to the joint. Applying just a "dash" of fresh solder to the tip/joint junction to speed heat transfer can save insulation, PCB pads, components, what-have-you.


All good points. I do that so automatically I don't even think about it.




Be careful when following the masses. Sometimes the M is silent.
October 30, 2021, 10:26 AM
ensigmatic
I missed this--perhaps because it was an "ETA?"

quote:
Originally posted by sigcrazy7:
ETA. Looks like I just answered my second question. I can get a whole assortment of caps from Amazon for $15.


quote:
Originally posted by snidera:
$15 for capacitors is a bit high, unless you plan on using the rest of the assortment.

This ^^^^^

Plus, with Amazon and things like this, you can't be certain of what you're getting. I've seen no end of the most astonishing CCC (Cheap Chinese Crap) being passed-off as the Real Deal on Amazon.

Again: I'd go to Mouser or DigiKey and order the exact parts I needed.

Solder is easy. For PCB work you want thin stuff. <Looks in electronics kit...> *hmph* The label fell off. I'd say the thickness falls somewhere between angle hair pasta and regular spaghetti Smile

The soldering iron is a bit trickier. I use a temp-controlled, grounded-tip soldering station I've had since about the dawn of time. But those are spendy--particularly for somebody who's not making a hobby of soldering electronics.

I'll leave it to others, who've purchased soldering irons more recently, to recommend on this one.

(For day-to-day work on most small soldered joints I use one of these: Wahl Solder Iron Kit)



"America is at that awkward stage. It's too late to work within the system,,,, but too early to shoot the bastards." -- Claire Wolfe
"If we let things terrify us, life will not be worth living." -- Seneca the Younger, Roman Stoic philosopher
October 30, 2021, 11:13 AM
PASig
Does it have to be FireWire?

The HDD doesn’t care what interface it’s connected to.

Why couldn’t you turn that into a USB 2.0 one?


October 30, 2021, 11:15 AM
mark123
quote:
Originally posted by PHPaul:
quote:
Originally posted by ensigmatic:
quote:
Originally posted by mark123:
If you don’t use solder wick you’ll pull up the pads on those mass-produced PCBs.

<waggles hand>...

Personally, I much prefer a solder-sucker. IME: Often the reason pads detach is too much heat was applied, poorly-fabricated PCBs, or both.


Just an opinion from a guy that was miniature and micro-miniature PCB repair certified in the Navy:

I think it's more common for pads to be damaged by too LITTLE heat applied for too long a time. Folks use undersized irons for fear of damaging the board or components and wind up pressing too hard and spending too much time trying to get the solder to flow.

We were taught to go in hot and get out quickly.

Another factor is CLEAN! Clean tip on the iron, clean solder and clean the pad before trying to desolder. Oxidized solder is a pretty decent insulator.

JMHO, YMMV.
Yes, use the wet sponge and a good tip.
October 30, 2021, 11:51 AM
snidera
quote:
Originally posted by mark123:
quote:
Originally posted by PHPaul:
quote:
Originally posted by ensigmatic:
quote:
Originally posted by mark123:
If you don’t use solder wick you’ll pull up the pads on those mass-produced PCBs.

<waggles hand>...

Personally, I much prefer a solder-sucker. IME: Often the reason pads detach is too much heat was applied, poorly-fabricated PCBs, or both.


Just an opinion from a guy that was miniature and micro-miniature PCB repair certified in the Navy:

I think it's more common for pads to be damaged by too LITTLE heat applied for too long a time. Folks use undersized irons for fear of damaging the board or components and wind up pressing too hard and spending too much time trying to get the solder to flow.

We were taught to go in hot and get out quickly.

Another factor is CLEAN! Clean tip on the iron, clean solder and clean the pad before trying to desolder. Oxidized solder is a pretty decent insulator.

JMHO, YMMV.
Yes, use the wet sponge and a good tip.

The brass(?) brill-o-pad cleaners work well too - no solder balls to fall off the sponge & get everywhere.