World's Worst Soldering!

photos not too clear, but looks like you need to be applying more solder. If there's black muck involved, clean the joint better.

NT

mebe theres something wrong wiht your browser as they show up v. clear indeed on my monitor at any rate. outstandingly clear in fact i would say. rotten soldering!

There may be hope for you yet:

1. How many watts is your soldering iron? It looks like the mess made by too low power or too fine a tip. 75 watt seems about right.
2. Is the soldering iron temperature controlled? If yes, raise the temperature and work fast. Mine runs at 750F (400C) for 60/40 lead-tin. If no, go shopping and buy a decent adjustable temperature controlled soldering station. Get a fine tip for fine work, and a thicker tip for the big stuff (so that the tip doesn't go cold as soon as you touch the work).
3. Are those 3300uF 25V caps 85C caps or 105C? The photo looks like

85C. If so, they'll last about 6 months inside a hot oscilloscope.

1. Clean the enamel off the wires with sandpaper before you solder. Tin the wire ends before attaching to a lug or PCB rivet.

I've dragged some of the local hams into my palatial office and demonstrated how easy it is to solder properly with a decent soldering iron. They're usually amazed at how well THEY can solder using my equipment. That's when I discover that they're using something from Radio Shack or that came with their childhood wood burner kit. I just did a quick scan of what's available on eBay and noticed that they now have OLED display aftermarket temp controllers for HAKKO soldering irons. I'm tempted: Also, if you don't have a hot air SMD workstation, this might be a good time to get one because they often include an adjustable temperature controlled soldering iron.

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Really bad.. Im suprised that the diods are still alive after that burn. Have to be a newly employed that did not get His/her 2hr education before doing the job

Den 2018-10-07 kl. 18:08, skrev Cursitor Doom:

Turns out you're right, the test card shows the grey scale is a mess. Settings can't fix it. Ah well...

NT

It's also fair to say that even with a right piece of junk one can solder properly if you have the skill. In a drawer somewhere I have a 1950s Solon where the tip hangs loosely, but it still solders ok.

NT

Cursitor Doom

Cool

Now that is an interesting bridge rectifier.

Here a raspberry replacing a big chip:

That thing has been working all day now since Dec 2013 without a glitch. Nothing to worry about.

Even older, 1985 or so, still works:

Na, it is OK.

I sort of like soldering, but only 60/40, maybe it is the lead ...

:-)

have many boards like that....

Scroll down can you find the SMDs on the board?

that is some Giggle Hz stuff too. It is still working, in fact added some stuff.

Soldering is simple.

You need a good temperature controlled soldering iron, some solder wick, some 60/40, and there you go. I count to 14 at 320 C for it to flow ... around pins.

:-)

A good soldering station and good hand tools (eg. - strong needle nosed pliers, shard edge clippers) are indispensable for repairing equipment properly.

I spotted what looks like "10..." curling over the edge on the edge of one of the caps, so he is at least using 105C caps. The caps should be secured though.

Sandpaper may be too aggressive if a rough grit, that can introduce scratches to the copper leaking to the potential for breakage. I suggest using something more like wet/dry emery cloth of about 1000 grit - true, it is another sandpaper, but less likely to scratch.

The invented bridge rectifier was poorly made for the space allowed, and those bridge modules are readily available. If you need to make a bridge module wrap the leads at least one loop around the others for a mechanical junction prior to soldering. Then there less risk of a solder joint breaking and introducing random loose parts into your equipment...

This looks handy - so I've ordered a couple for the shop:

Nice to be able to check calibrations by comparison.

John :-#)#

People often overestimate the strength of solder - it's close to zero. Always make some sort of mechanical bond first, or reliability will not be yours.

NT

Unfortunately not!

I have 15W, 25W, 40W and 80W irons. This atrocity was carried out with the 15W one which has a pointed tip for some reason.

You're very kind in attributing this train wreck of a repair to my having the wrong tools, Jeff. Sadly I don't believe it's the case. This kind of work requires a steady hand and a keen eye and I possess neither.

I followed the original spec as far as possible. The originals were

5500uF, 30VDC and 85C. I couldn't get the right capacitance within the space available so used 33's in parallel. The old 85C's lasted for decades so your 6 month assessment may be a bit pessimistic.

Yes, I did do that. I know what I *should* do but it doesn't help.

Can you imagine the carnage I'd leave behind attempting SMD stuff?? :-D

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I scrape magnet wire with an x-acto knife. That leaves a shiny surface that wets nicely. I think the professional wire strippers use rotating knives.

A serious high-power, controlled temp iron is basic to good soldering. I like my Metcal.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics

15w is way too low power for what you're doing there. 25w & 40w are the ones to be using. 15w is better for smd work, hence the pointed tip.

You'll learn. We'll give you a hard time till you do.

NT

John Larkin wrote

that burns the magnet wire insulation, and then you can just tin it. Scraping damages the wire. But watch out for the terrible possible toxic smell.

I have a brush that uses fiberglass. Cleans quickly, bends a bit to get the rounding needed, and doesn't run any risk of nicking the wire.

Something like this:

Also polishes edge connections, etc. a very useful tool.

For regular board work I like my Weller stations with the magnetic temp controlled tips, I mostly use the #7 medium or thin screwdriver tip.

John :-#)#

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On Sunday, October 7, 2018 at 1:36:19 PM UTC-7, snipped-for-privacy@nospam.org wrot e:

I use a match to burn off the insulation. Sand paper also works without ni cking the wire. I think I saw some kind of chemical stripper in the electr onics catalogs, but I never tried those.

It seems to me that instead of a certain wattage of irons, the way to go now is an iron with high wattage, say 50 or 70 watts but is temperature controlled. Then match the size of the tip to the size of the work.

Those hot air stations from China for about $ 60 seem to work fine for me as I am just doing it as a hobby and only use it once ever couple of weeks. The hot air works well for the heat shrink tubing and sometime to remove a daughter board from the mother board if it only ha a few pins. The iron heats fast and comes with several tips.

Stay away from any solder that is not 60/40 or better 63/37. Size the solder to the job. Maybe adding some extra flux will help you.

The high temperature iron sometimes works and sometime not depending on the wire.

I usually use a Bic lighter and one of the Scotchbrite pads to finish cleaning the wire.

Beldsol and some similar wires are meant to be thermally stripped.

Not #14!

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics

wrote in news:ppdl16$1gq8$ snipped-for-privacy@gioia.aioe.org:

60/40 is for plumbing.

The electronics industry settled on and proved to be the best 63/37 and for decades it was. This RoHS shit is the worst thing the world ever did. Metallic form lead is not dangerous to the environment.

If it were, there would be huge lead levels around all the damned police shooting ranges in the nation. There is not.