Electronics Soldering Information


This is a compilation of information on how to solder electronic componentry and what to use to solder with. I received my soldering education via NASA Langley's Soldering School way back in 1977. I have compiled the following guides and supplemental information in an effort to aid both the novice and the experienced technician alike in the art and science of electronics soldering. I hope you find the following useful and informative.



Soldering Guides

Below are guides for learning about how to solder for the novice electronics hobbyist. The Electronics Club Soldering Guide in particular presents good information on developing good soldering skills. The Soldering Comic Guides are also quite useful particularly for the younger hobbyist as well as insightful light reading for the experienced hobbyist.

Soldering Guides
[How-to] TopicElectronics Club Soldering Guide .pdf file

    Soldering Comic Guides
[How-to] TopicSoldering Comic Booklet 11x17 - English .pdf file
[How-to] TopicSoldering Comic - English .pdf file
[How-to] TopicSoldering Comic - Japanese .pdf file


Soldering Station

Below is one of the very best entry level production soldering stations on the planet, the Hakko FX-888D. It is designed and manufactured by Hakko of Japan. This is no cheap Chinese knockoff with little or no manufacturing quality control. This is the real thing manufactured in Japan with exceptional quality control during manufacturing. Not only is the unit itself attractive with excellent fit and finish, it utilizes a Hakko patented ceramic heating element with an integral thermal sensor that heats and cools rapidly allowing quick adjustment of tip temperature. Not only does Hakko offer a large variety of high quality tips for this soldering station but every part for this unit is individually available from Hakko as replacement parts. Take it from me, although it is a bit pricy, you will not be disappointed with the performance of this soldering station. It is available from All-Spec Industries.
For Printed Circuit Board (PCB) through hole component soldering I like to use a small hoof tip (Hakko T18-C2) and set the tip temperature between 600F to 650F. For wire to wire or wire to connector soldering I like to use a small chisel tip (Hakko T18-D16) and set the tip temperature between 700F to 750F. For Printed Circuit Board (PCB) surface mount (SMD) component soldering as well as very fine component soldering I like to use a fine SMD tip (Hakko T18-S4) and set the tip temperature between 600F to 650F. To improve thermal conductivity I like to slightly tin the tip (add a little solder to the tip) before contacting the parts being soldered. Finally, prior to shutting down the soldering station I like to moderately tin the tip to prevent oxide formation on the tip itself. Upon restarting the soldering station, once the tip comes up to temperature, just wipe the heated tip on the damp sponge tip cleaner and start with a freshly tinned tip.

Soldering Station
[How-to] TopicHakko Brochure FX-888D .pdf file
[How-to] TopicHakko Instruction Manual FX-888D .pdf file
[How-to] TopicHakko Product Bulletin PB330 .pdf file
[How-to] TopicHakko 936 Calibration .pdf file
[How-to] TopicHakko Tips .pdf file



Solder

The question always seems to arise between novice hobbyists as well as seasoned professionals alike, as to what type of solder wire should be used for a given electronics project. Aside from special applications requiring high silver (Ag) content solder, my personal favorites contain cored flux formulas 44, 285, and 245 produced by Kester. The purpose of using flux during soldering is to remove any oxides on the materials being soldered. Failure to so will yeild poor solder to metal bonding resulting in compromised electrical conductivity. Soldering flux comes in many forms, liquid, paste, and cored solder wires, just to mention a few. My preference for electronics printed circuit board (PCB) based projects is to use a cored flux solder wire that is 50% to 66% flux. Note here that although the metals comprising the solder wire have a very long shelf life this is not true with the flux core, whose shelf life is between 3 to 5 years. Although you may be using flux cored solder wire that is much older, take it from me through personal experience, that the flow characteristics as well as the oxidation removal properties of the flux core have been greatly compromised. This generally results in poor, or at the very least, ugly solder joints. Do yourself a favor and properly dispose of any flux cored solder wire older than 3 to 5 years. Formula 44 rosin flux is the old reliable activated rosin (RA) flux thats been around for decades. Formula 285 is a mildly-activated rosin (RMA) flux that is less corrosive than formula 44. As of late though, I lean toward their formula 245 flux, which acts like a mildly activated rosin flux but is not rosin based. It is less corrosive than the formula 44 activated rosin or the formula 285 mildly-activated flux and is advertised as a no clean, RoHS compliant formula. By the way, no clean soldering flux does not mean it does not leave any residue, it means that the remaining residue is non-conductive. Formula 245 flux eliminates the requirement to remove the flux residues and reduces the amount of flux removing solvent required to clean the printed circuit board after assembly. I tend to use 63% zinc (Sn) 37% lead (Pb) solder as opposed to the 60% Sn 40% Pb composition. The reason for this is that the Sn63/Pb37 composition solder has superior flow characteristics and is less plastic making it a better choice for Printed Circuit Board Assembly (PCBA) applications as opposed to the Sn60/Pb40 composition which is a better choice for wire-to-wire connections. Note that lead based solders are about half the price of the lead-free varients. I have been using lead based solders for over 45 years without any sign of heavy metal poisoning. The decision whether to use leaded or lead-free solder is entirely up to you. My personal favorite general purpose electronics PCBA solder is Kester No-Clean 245 Solder Wire, 0.031" dia., Core Size-66, Composition Sn63/Pb37, which I purchase in 1 pound rolls. This solder is available from All-Spec Industries, Part #KW24530.

Solder
[How-to] TopicKester  44 Flux-Cored Solder Wire
[How-to] TopicKester 285 Flux-Cored Solder Wire
[How-to] TopicKester 245 Flux-Cored Solder Wire



Desoldering Braid

I have discussed in some detail how to solder items together. What do you do when you make a mistake or just want to redue something soldered to a PCB? There are several solutions from high priced professional Desoldering Stations to budget priced Solder Suckers. My personal favorite though is #2 Desoldering Braid, otherwords known as Solder Wick. It is important to use a high quality product here as, through personal experience, I have found that cheaper Desoldering Braid just does not have the wicking action of the premium products. To properly use Desoldering Braid pull several inches out of the container but leave it still attached. Next I open up the weave a little bit by holding the end of the Desoldering Braid and using a gentle side to side motion. Now sandwich the Desoldering Braid between the joint to be desoldered and the soldering iron tip. The solder should be wicked by the Desoldering Braid as soon as it becomes molten. A word of caution, do not over heat the part or the PCB as this could result in permanent damage to both. I like to use a small hoof tip (Hakko T18-C2) setting the tip temperature between 650F to 700F to perform this type of desoldering. As you continue your desoldering, it is important not to let the Desoldering Braid act as a heat sink, so trim the spent Desoldering Braid every inch or so of use. If the joint solder fails to wick it is helpful to add a little bit of solder to the existing joint prior to wicking. This often aids the wicking action if there is insufficient solder at the joint to wick. Below I have listed a couple of premium quality Desoldering Braids. I like to use the #2 Size (0.055" width) Fluxed Desoldering Braid and purchase it in 25 foot spools. Both the Chemtronics Solder-Wick and the Techspray Pro Wick Desoldering Braid are made in the USA. The Chemtronics Solder-Wick - Item No. 50-2-25 is available from Digi-Key Corporation. The Techspray Pro Wick 1802-25F - Item No. TOL-80755 is available from All-Spec Industries. Note that the Techspray product contains RoHS compliant flux.

Desoldering Braid
[How-to] TopicChemtronics Solder-Wick .pdf file
[How-to] TopicTechspray Pro Wick .pdf file



Soldering Accessories

Some of my favorite soldering accessories and hand tools are listed below.
I like the Jameco Item No. 141761 Solder Reel Stand for its quality, weight, and non-slip/scuff-resistant base, not to mention its ease of use. I do not require a soldering iron holder as part of my Solder Reel Stand since my Hakko FX-888D soldering station comes with an exceptional soldering iron holder.
Its also a good idea to use a premium quality flux removing solvent that matches up with the flux type used. My preference here for the Kester 245 No-Clean flux is the Techspray G3 No-Clean Flux Remover available from All-Spec Industries. The Techspray G3 based flux removing solvent is a non ozone depleting replacement for the very effective CFC based solvents used in flux removers of yesteryear. Note that this flux remover is effective on all flux formulations except for lead-free and synthetic activated (SA) formulations. Of course you'll need an ESD Safe cleaning brush to scrub the PCB after spraying it with flux removing solvent. I recommend the inexpensive, ESD Safe cleaning brush listed below from Adafruit Industries.
As far as hand tools are concerned, my two must have pliers are the Xuron Corp. Long Nose Pliers and Flush Cutters, both with ESD Safe handles. Both of these hand tools are made in the USA and are of very high quality.
To hold your PCBs and other work I highly recommend one of the most versatile vises on the market, the PanaVise 300 Series Vice. A large variety of heads are available for the Model 300 base allowing you to hold just about any item you wish to work on.

Soldering Accessories
[How-to] TopicJameco Solder Reel Stand-#141761
[How-to] TopicTechspray G3 No-Clean Flux Remover-#1634-12S
[How-to] TopicESD Safe PCB Cleaning Brush-#1209
[How-to] TopicXuron ESD Safe Long Nose Pliers-#485AS
[How-to] TopicXuron ESD Safe Flush Cutters-#410ASF
[How-to] TopicPanaVise Catalog (11.27 MB) .pdf file



Last modified:
20 August 2013
By: E.P. Mueller