Soldering tutorials, avionics style

[Aldobrandi]

Hi all,

Forgive me if this has already been posted but I stumbled upon some interesting soldering videos on Youtube and thought they might be of interest to the community. http://youtu.be/Vynb_HdEIDU
In a word, it is soldering performed to meet avionics standards, and let's just say this guys really likes cleanliness  (he even cleans the solder wire itself with IPA which I had never seen done before). Anyhow, there are plenty of other interesting videos on his channel. Enjoy!

Cheers,
Jerome.

[xrunner]

That's a lot of work for a resistor, but, if it's going up into space I guess you have to do all that - 'cause there ain't nobody up there to fix it if it breaks. 

[Aldobrandi]

Hi other tutorials are just about as crazy. You can tell a man who likes a job well done! I wonder how much time it takes them to populate entire boards, surely when not slowing down to give explanations he probably could have soldered this resistor in a matter of seconds 

[manticore00]

Very fun to watch. I don't think I'll be nearly as diligent with cleaning as him but I like the technique of bending the leads in the direction of the trace and how to gauge how much of the lead to cut off.

[CompElitePC]

Go NASA!   its like watching Monk  however that is the best you can get.

[SeanB]

Remember this is teaching good technique, if at least 70% sticks then it is good. Wish I had as good a set of tutors when I was in training. I landed up doing a lot of tutoring of others who were bright, but did not understand electronics well. You know you have trouble when a guy wires a transformer up the wrong way round and turns it on........ Pretty impressive, as we had just finished winding them from scratch, making the coil formers and clamps, though we had a winder and premade laminations ( I would have dreaded varnishing 300 steel plated after punching them out of a sheet) to help us. Still have it around somewhere.

[c4757p]

Remember this is teaching good technique, if at least 70% sticks then it is good.

A very good point. It's always good to teach more care than you actually want - you'll never get quite as much as you teach.

[IanB]

You know you have trouble when a guy wires a transformer up the wrong way round and turns it on........

Well obviously the mains is much more powerful than the low voltage side, so of course you connect the mains to the big chunky wires, not the thin feeble wires 

[SeanB]

A very good point. It's always good to teach more care than you actually want - you'll never get quite as much as you teach.

I was cheesed with one lecturer at Atlas, I wanted 100% for the exam, he gave me 98%. 2 weeks of solid training, we only spent one afternoon touring through Bonaero Park and getting the whole 20c tour after the exams were done and dusted. Still, the place now is a ghost town, all closed up, empty and all the know how that they developed over the decades ( and they were bloody good at it, a lot went to either the USA, UK or other countries) is split up and gone for good.

@IanB he was not the brightest spark in the room, except for that one flash of brilliance. This was just after the 5th lecture on how to wire them up as well.

[fpliuzzi]

Hello,

What follows is my non-engineer take on high reliability soldering. NASA soldering standards were quite high indeed. I had to be re-certified each year for the 15 years that I spent in the Aerospace industry as an electronic assembly technician (some of the GPS satellites have my fingerprints on them). It was a fascinating experience.

The finished circuit boards had to be extremely clean so that the conformal coating would adhere properly to them, and also so that any residue on the PCBs wouldn't outgas when up in the vacuum of space.

Space is a pretty hostile place for electronics. First, many of the satellites had to survive the incredible vibration level of launch when they were sent up on the nose cone of a rocket. The electronics also had to survive high radiation levels, wild temperature swings, and the effects of vacuum while up in orbit.

As shown in the video, component lead forming was also important so that you did not stress the area where the leads met the component body.

Special end-cutters were used to cut the component leads to a specific length before soldering  (0.040" in the cutters shown in the link below). They cut the lead without sending a shockwave up the lead to the component body. Back when I was doing this type of work, many of the chips on the boards had fragile glass seals where the leads entered the chip's body.

www.hmcelectronics.com/product/Excelta/530E-US?referrer=googleshopping&gclid=CJC726j167cCFY-Y4AodgUwApg

Like anything else, with some experience, component tinning, forming, lead cutting, and soldering went fairly quickly (much quicker than what's shown in the NASA solder training youtube video, or they would still be building Sputnic 1). The completed boards were cleaned in a heated vapor, degreasing tank and rinsed in alcohol.

Regards,
Frank
.

[ampdoctor]

Some of their tutorials are quite good while a few other ones look more like a chinese fire drill.

Here are some seriously good links to more practical high performance soldering technique. Excellent close ups, commentary and explanation. For anybody looking to learn proper soldering practices, these are probably the best I've seen on youtube.
https://www.youtube.com/user/SolderingGeek/videos?flow=grid&view=0&sort=da

[Aldobrandi]

Thanks for posting these, I thought I had lost them forever!

[vk6zgo]

Telecom Aust. ran a "High Reliability Hand Soldering" course,back in the 1970s which taught us the same method of soldering,complete with cleaning & trimming your solder.
I've used that method ever since--it doesn't take any longer!

Just as an experiment,grab a tissue wet with IPA or other solvent,& run it along a length of solder.
You'll be surprised at the amount of crud which comes off!

"Clinching" component leads was not allowed by Telecom Aust,except in special cases,as  "de-clinching" the leads made replacement time longer if a repair was required.

He made a big fuss about brushing the solder off the iron into the special container,but what about the little bits snipped off the ends?

I once opened a piece of equipment where extensive rework had been performed.
The person who did the work used this technique,producing immaculate connections---but he left a whole lot of tiny solder offcuts lying around all over the board.

[cthree]

nice find.

[G7PSK]

He should be wearing white cotton gloves, Whenever I went into the high end electronic manufacturers in and around cambridge all the assemblers and technicians wore white cotton gloves so as to not leave finger prints on the boards and also to protect their hands from the solder.

[vk6zgo]

The gloves get dirty & end up transferring more crud than ordinary clean hands.

[Majorstrain]

I can understand the reason for cutting the solder and not cauterizing the end of it by burning it off.

But isn't that what happened when he tinned the iron before making the joint.
I would have thought it better to clean both ends of the solder and use one end to tin the iron and flip the solder around to make the joint with the other fresh end.

Just nit picking.

You go through a heap of Kimwipes and IPA strain gauging as well.

Mmmmm! love the smell of IPA in the morning.

[KD0CAC John]

I saw that also and thought it was a waste of time , at least from learning much , I know that NASA has to go the extra 1,000 mies .
I think this is much better for the rest of us .

[lemmegraphdat]

Tin the iron. Clean the work. Solder goes where the heat is.

[vk6zgo]

I can understand the reason for cutting the solder and not cauterizing the end of it by burning it off.

But isn't that what happened when he tinned the iron before making the joint.
I would have thought it better to clean both ends of the solder and use one end to tin the iron and flip the solder around to make the joint with the other fresh end.

Just nit picking.

You go through a heap of Kimwipes and IPA strain gauging as well.

Mmmmm! love the smell of IPA in the morning.

Yeah,he blew it!!

Your suggestion is just what you do in real life!
Telecom used a special solvent instead of IPA,but it smelled bad!
At home,I use the stuff we call Methylated Spirits in Oz,& ordinary tissues or toilet paper.

"Metho" is supposed to leave a dreaded "white residue" but unless you are cleaning lenses,I suggest it is more a cosmetic problem than anything else!