How not to solder!

[Blastcap]

We are all wetting our tips.
But he is applying the bulk of the solder by melting the solder on the tip, and lets it flow over the iron on to the joint, and not applying the solder directly to the joint.

[nanofrog]

I always melt a small amount of solder on the tip before soldering.

A completely "dry" tip won't make good contact with the pad/pin to be soldered and it will take a lot of time for them to warm up.

If the tip is slightly "wet", you can go through solder joints really quickly and there's less risk of damaging a sensitive IC.

This is proper practice to get good thermal transfer. 

But there's a difference; you're adding solder with fresh flux to the joint, not solely relying on what you wetted the tip with to make the joint without even adding any additional flux to the pad & lead.

SMD changes this a bit (can solely use the solder on the tip), but it still requires the leads & pads to be fluxed prior to touching them with an iron (i.e. drag soldering with a tip that has a hollow in its face).

[ivan747]

... more flux than Louis Rossman likes to use...

Makes me wonder if be buys it by the barrel or so.

Me too, man, me too.


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[rdl]

... more flux than Louis Rossman likes to use...

Makes me wonder if be buys it by the barrel or so.

He might.
I remember him mentioning in one of his videos that it's sold in his store.

[Ian.M]

IIRC he buys it by the case from Amtech. See https://www.eevblog.com/forum/repair/rossmann%27s-repair-videos-using-tons-of-liquid-flux-for-no-apparent-reason/.  He's in NY so time is money + he has a swept ultrasonic cleaning tank so its cheaper to use plenty and save time than to be stingy with it and take longer.

[RGB255_0_0]

Yeah and he resells it.

[SeanB]

Plus he is showing you the microscope work, where 1ml of flux will appear to be a very large lake on the board. Remember the components on the board, while looking large, are actually sub millimeter in size.

[Macbeth]

Plus he is showing you the microscope work, where 1ml of flux will appear to be a very large lake on the board. Remember the components on the board, while looking large, are actually sub millimeter in size.

Father Ted teaching Dougal about this...


It does look disgusting the amount of flux Louis uses, the scraping of damaged pads, etc. but he himself says he is the worst at soldering in the world. I think he is just being very modest, when you realise how tiny those parts are.

I would really love a decent (Tagarno?) microscope. A bit too pricey for me, so the magnified lamp or headmount loupe will have to do for now.