What Solder Do You Use?

Kester 24-6337-6422 15mil diameter solder, SN63PB37, water soluble flux

(* jcl *)


Do any of you guys know about this “trick”?:

Is that liquid flux being used (the clear fluid being dripped/flowed on the pins before soldering)? Do you think he is using regular solder or something else?

It looks like a slick and easy way to solder such devices!


Yup, that works. It is liquid flux…very good stuff. Note that I think he is gluing down his components first else they would move, of course. You can tack-solder some pins down on the other side instead.

It should work just fine with regular solder, and a lot of practice :wink: Make sure you have some good (and thin) solder wick around until you do get that practice as you will be forming solder bridges until you get the feel for using the right amount of solder and motion.

It actually looks like he tacked some pins down. So that “drag” soldering works?

problem with drag soldering is, you catch 1 pin your going to solder together a nice little bent pin lump nightmare

be careful

Note that I think he is gluing down his components first else they would move, of course.

Yeah, I noticed that - what do you think is being used for glue? Is it an epoxy or a cyanacrylate (super-glue)? Or something else? Silicone maybe?

When I get around to trying my hand at SMT, I plan on starting with 805 sized resistors and caps, maybe some larger transistors (if I need them), and LEDs - then move to larger pitch SOICs, etc. Maybe practice on an old board or something.

It actually looks like he tacked some pins down. So that “drag” soldering works?

He makes it look easy, doesn’t he? If you notice, he’s got the board nearly vertical; I think that is one of the “secrets” - which is why the components are glued/tacked down. I think the vertical orientation helps in some manner with the flow of solder, and with the extra flux keeps the bridging to a minimum (in one part you can see he makes a bridge, but a quick go-over again fixes it).

Fortunately I have a board vice that should be able to hold in that orientation (I may have to get an extension arm to lift it up higher).


The drag soldering works well. I use the bottom of the bent tip and lots of flux (followed by lots of cleaning :wink: I tack two or three corners depending on the IC.

I have not tried the vertical dragging. The horizontal dragging works quite well.

For just starting out I would recommend 0805 or larger, SOT23 (wherever possible),
SOIC (1mm pitch or larger). Soldering 0.5mm pitch is not bad (FTDI chip).
A good iron and lots of flux.

(* jcl *)

Nice Demonstration:

In the demo, he says he uses “EcoWave 45” soldering flux. Nice stuff based on his demonstration.

About $13.00 US for 550 ML.

I believe that this soldering can ONLY be done with good flux… and not just what is in the solder itself. I personally only use high silver content solder if I use lead-free.

The flux I currently use for Surface Mounty work is a MUST CLEAN type… but it works great… especially when drag soldering.

I always prefer legacy solder that does contain lead.

(I have been a wave solder machine operator in the past… so I sort of understand that guy’s passion)

Drag soldering is a very easy way to solder multiple pins and the best thing is anyone can do it!

I’ve done it with cheapo firestarter irons and poundland solder :wink:

If done correctly, there will be no bent pins but occasionally you will get a bridge or 2, nothing some wick wont sort. Just use plenty of flux, a clean iron with a small amount of solder(it will do more than you think) and with moderate speed slide the iron over the pins. Job done :slight_smile:

Lately, I’ve been using this…

Before that, I was using 63 Sn / 37 Pb.

I “borrowed” the solder I use from my grandad, it is about 1mm diameter and probably contains far too much lead, but it completely pwns. The flux is liable to be a bit sticky and hard to get off though as it seems to burn really easily - that might be me though. The solder must be over 40 years old.

watch that old stuff on things you want to keep, it could be acid core, and if not cleaned up can foul up things over time

Oh, I have been assured by a friend (called Ted, he used to do soldering for HP) that it is flux. Any ideas on cleaning btw?

I use rubbing alcohol and horse hair “acid” brushes, you can buy em online or at half the cost at your local hardware store by the welding supplies

I use a very crapy solder.

Circuit-test Rosin Core Solder
60% Tin, 40% Lead, 1.0mm

I hate it, stay away from it.
It must be because of the package it comes with…