goal for 2023: use a conical solder tip and enjoy it

I've been tempted by this thread to try a chisel tip.  Up to this point, I've only had conical.  My favorite one is the slightly offset tip (900M-T-IS).

Seems that my post convinced more people to abandon conical than to learn it 

Perhaps, if it corrodes there. Or it could shock the entire board (although most components are a lot more rugged these days than they used to be).

I don't know the chemical reasons for it, but I guess the exposed copper/plating/solder could interact all together with moisture and air.

I doubt it matters at all with modern components being used indoors, but it's a habit (and does mean the joints visually look nicer with solder all over them!

It's seen a lot in videos from (say) Adafruit etc. Wrong though! (I mean if they are going to teach, they may as well try to do it properly, since it's little effort).

Also depends if the cut is to be coated afterwards or not.

https://workmanship.nasa.gov/lib/insp/2%20books/frameset.html

I think it is still cut first, i.e. this was a scenario where the soldering didn't cover the top of the joint despite it being cut beforehand. Not sure! 

I guess this shows it must be a chemical reason, e.g. corrosion.

I have an opinion®:

the cut end of a lead is exactly the same material as all the rest of the lead. And that's exposed too.

Yes, I was referring to the base metal sealing there.

Strange that they let that one through though given some of the other stuff.

I think this is the one you are after about cutting stress

I've not read the NASA standards, but it would be surprising if they allow component leads to be snipped on a PCB after the component is soldered. (merely from what I observed in mil-product hand assembly).  I know nothing about metallurgy/chemistry, so I'm speculating it is shock and corrosion related. But the conformal coating comment does seem to align with the corrosion theory (at the junction of the exposed copper/plating/solder perhaps, but I have no idea). 

Here is what is done in avionics: https://www.youtube.com/watch?v=Vynb_HdEIDU . Whatever you do currently, it will not be good enough for these standards. (and yes, the cut before soldering)

You could be right, but instinctively if I see exposed copper on the end of a component, I tend to solder over it. Just habit.

'Properly' kind of depends on which standards you are working to though.

Also it doesn't help that some of those standards are expensive to get hold of and certification even more expensive...

'Properly' kind of depends on which standards you are working to though.

Also it doesn't help that some of those standards are expensive to get hold of and certification even more expensive...

We could rephase to "more properly " I guess : ) There are some things that seem to be common to all the standards, but some people take shortcuts like combing all the leads down like hair first, for all the components, and then soldering and then cropping. I think I saw it in an Adafruit or Sparkfun video. It might save half an hour on a project at most I guess.

That is true. I run across NASA standards periodically and they provide some interesting insights, but are often different form other standards on the same topic. That said, I violate virtually every standard when I solder, and I'll even cut my own corners when some other requirement has higher priority. Like trimming the lead way too close to the card because there isn't enough room for a good solder joint. I do at least try to make the joint work for its intended application, and so far it is working out.

beacon_dave said:

'Properly' kind of depends on which standards you are working to though.

That’s how I feel about it too. I imagine NASA would be the highest standard given the conditions the electronics for avionics and space flight would be used in: extreme vibration, temperature, and pressures. Maybe exposure to chemicals and gases too.

Adafruit is geared towards hobby projects, so I imagine they’d rather not scare off the newbies with that level of precision! Similar for any beginner type classes.

My standards will be slightly below that hobby level 

I do want to start making them more visually appealing though, which includes cleaning of the flux and having more consistent solder joints.

Leaving flux uncleaned - guilty as charged. 

Maybe we should start a discussion  topic - How not to solder...