Now I have the idea of a small soldering competition circuit board floating around in my head. It woudl be great is we had a tri-colored LED (or maybe a number of individual LEDs) and we could arrange it so that bad solder joints affected the LEDs in some way ... but maybe I'm over-thinking this...
All this talk about soldering reminds me of Day 2 at college. The instructor passed around squares of plywood filled with nails along the edges. We had to create a criss-crossed array of bare wires using the nails as anchors and solder them at every junction.
Many folks learned soldering through building of kits, Heathkit included a soldering how-to manual with every kit. Funny how the worst solderers were TV repairmen, followed by ham radio operators. Most first-timers followed the tips and did a decent job.
@Max:"It would be great is we had a tri-colored LED (or maybe a number of individual LEDs) and we could arrange it so that bad solder joints affected the LEDs in some way"
Practical Components: http://www.practicalcomponents.com/ offers some soldering training kits. Some of their kits come with a PC board and a special quad flatpack "dummy" chip that has some pins internally connected to each other. The idea is that you solder it to the board and then check the continuity between two pads on the PCB. The circuit zigzags in and out of the chip package through all of the pins, so if you've got continuity, you've either got all the solder joints right (or at least conducting), or you've got a solder bridge.
Max - "....if we were to hold a soldering competition at EE Live! 2014,"
If I make it I'd give it a go. Time us Aussies took something else off you guys besides the Americas Cup :-)
" I recently constructed a 4x4x4 tri-colored 3D LED cube kit that required 400-plus soldered joints... needless to say it worked the first time I powered it up (well, actually, if truth be told, this was the first project I've ever built that worked the first time, but let's not rain on my parade as it were)."
Rats! I was looking forward to you sending it to me for final commissioning..... :-)
Just fired it off at the wire end and sploog ends into a mug of acetone.
Power electronics lab style - we went thru several CO2 extinguishers per week.
The Cooner was for for large air cored toroids - just don't forget the anti-poloidal turn!
Having over 24 TO247 mosfets blowing up behind your back was a wee bit of a regular nuisance, and that was regular. Not my design but an inherited inverter that was sacrosanct. I came up with an cheaper IGBT version, ~200kHz switching, ~100kHz PLL resonant ZVZC switching and then quitely walked away from that job. That was 18 years ago.
As to why Radiologists' wanted 150kV @ 80kW, no idea. A zoo VET might need such a thing, but for humans?
It can be fairly subjective, but much of it can be measured. The IPC 610 standard describes things like fillet height, distance for fillet to clipped lean, part position on pad and such.
You could also judge to differnet levels of expertice so the experience folk wouldn't always runaway with the prises. The same standard has different levels: Class I (the minimum acceptable), Class II (appropriate for consumer goods), Class III (military & hi-reliability).
Soldering with the 300 watt had soldering iron was a real pain at 10 years old the Iron was so heavy to hold.
Multi strand Litz wire tails from a tuning coil were the killer of dry joints for me, until dad showed me the trick of soldering it. Dip the cotton and shelac coated wires in alcohol, set light to the end and wait for a lovely bright glob of copper to form and then blow the flame out and then solder. Oh what lovely mini fires I had with this.
It seems to me basic soldering skills are something that needs to be taught on the bench, preferably in a flame proof room.
@Crusty....working on military radios I had similar problems with the "Tinsel" wires used in handset and microphone curly cords. The trick was to get a strand out of multistranded wire, and use it to bind up the tinsel cores. You could do a very neat job with practice.
@David: I think my first head of department at London Underground Research Labs showed me how to do it and it mainly concerned getting the oxide coat off with fairly normal lab reagents, and then quickly soldering.
@Max; While thinking about a soldering competetion you could make life interesting by getting the contestants to measure the resistance using a slide wire potentiometer and Weston Cell. How many have used similar old kit?
I used, once, a Cambridge optical pyrometer at college, but I have never seen another one to put my hands on.
@Duane: In my case the burns would be palm prints, as that 300 Watt soldering iron I mentioned, used to rest on a bunsen burner tripod. Two of us working at one bench, it had to happen, my co-worker put the iron the wrong way round, so i got the heating element embossed in my closed hand. Ouch. After nearly 60 years the marks are almost gone, but the memory lingers on.
Sheesh Max, here you go again threatening to make our lawyers' heads explode hosting a soldering competition at a live event. But (and it's a big but) if our readers want, er demand it, I will start looking into it. I'd hate to face your wrath if I didn't deliver.
Now that's something I should've thought of 3 weeks ago. I am having a denture made- If I had allowed for a gap between two of the teeth and had the edges sharpened I could probably claim the denture as a work expense!
@Max: With the thousands of miles of MICC I accepted for the fire alarms at London Underground post Kings Cross Fire, I almost became a world aclaimed connoisseur of MICC cable installation.
I can still walk around the sations and say which crew installed a particular section, just by looking at the way it is dressed into the building fabric. I think LU took the whole output for England for two years, some say the total length used would reach the moon.
If you are going to downgrade a cable then you have to be as good as the men installing, so I learnt to dress and terminate MICC. The Japanese joke that MICC is the English plumbing electricity, it has to be installed at site and can not be pre-constructed in a factory.
I have got data rates of over a Meg across a kilometer of MICC which considering it was not designed for such use is amazing.
But correct after working 7 nights a week for two years installing/accepting the LU fire alarm systems Mrs Crusty does not allow me out that much.
To really find the best of the best, the finalists need to solder 0.7mm (or thinner) soldering wire to itself ie make a loop. Then add another and another to form a long chain. It can be done; I was an expert 35 years ago. Using a modern electronic temperature controlled solcering irons is cheating!