Followup: Soldering How-To

The response to the soldering How-To was fantastic. You guys seem to want more and we’re looking forward to bringing you more How-Tos in the near future. If there’s a specific topic you’d like to see, let us know and I’ll see what we can do.

[justin] suggests picking up a flux pen with your next electronics order. I’ll probably take him up on that idea. [xrazorwirex] suggests using a pure form of alcohol like everclear for cleaning boards. I keep a few bottles of tape head cleaning solution – it won’t leave residue like rubbing alcohol and you don’t have to be 21 to buy it. [MattS] suggests cutting your leads and then soldering to prevent corrosion later on. This usually isn’t a problem for small projects, but it’s a good idea for anything that’ll see a less than ideal environment later on. [Josh Malone] is fond of his Hakko 936 soldering iron. I have to agree with everyone that a temperature controlled iron is the way to go. I was very happy with my Tenma which lasted well over 10 years. [David Moisan] suggests buying purpose made soldering sponges from MCM to preserve the plating on your soldering tip. Considering the varied contents of kitchen sponges, this is definitely a good idea. [Forrest M. Mims III] freaked me out a bit when he commented on the post – he notes that he taught his son to solder when he was 4 years old! I’m a bit more conservative, but lets be honest – I learned how to solder from his books when I was a kid.

30 thoughts on “Followup: Soldering How-To

  1. I’m a fan of metcal soldering stations myself. Used them for years at work. Also wanted to mention using distilled water in your sponge vs. tap water. It will help your tips last longer.

  2. i still have the forest mims books i bought back in the 80’s when i became interested in electronics. very fond memories. i’m sure 10s of thousands of us started with them.

  3. “[Forrest M. Mims III] freaked me out a bit when he commented on the post” – You’re telling me! He has a lot to answer for, as it was his books that started me off. 15+ years ago when I first read one on the 555, I’d never have thought that I would end up designing microprocessors that go into almost all mobile phones, PDAs, media players, printers… Sir I thank you and I take my hat off to the new generation that are showing their warez via Hackaday

  4. I’d love to see a more in depth article on pcb prototyping at home. I’ve seen a few around on the net but they’re not too detailed.

    Also basic starter projects would be awesome, sourcing out the parts (ala sparkfun) would be a sweet addition as well.

  5. I loved the soldering how to, as i am a fan of hacking/modding equpiment to suit my needs, but i am new to the whole building my own projects scene, what id really love to see would be some how-to’s on other basic things, like using multimeters and what the information it gives means, some simple write ups, like [ladyada]’s tv-b-gone(which im buying the kit as soon as i can afford it) and the like

  6. You can find 100% isopropyl alcohol at Costco. That’s the stuff. 70% stuff at the drugstore is nasty and the 91% alcohol is not much better.

    Also, I used one of those cheap Rat Shack irons for years, the one with the interchangeable heating elements that screwed in. I kept it going for a long time by using antisieze compound, which you can get at an auto parts store, on the tip threads. And also by buying the “good” iron tips instead of the cheap caca copper tips they sold.

  7. As i work in electronics i like those metal wool balls for cleaning. we solder our parts in then cut the legs, wash the boards under hot water with dishsoap. then after boards are tested and calibrated we spray them with a confroming silicon spray from mg chemicals. that does great at preventing corrosion.

  8. for as much as i like the altoids tin pocket amp, does anyone know of a similar project that can be used as a portable/battery powered-guitar amp? or, best of both worlds, a circuit (either with two inputs or a switch) that can take a line level or a guitar input, and amplify either to headphones level.

  9. I am new to the whole DIY electronics game. With some help from my computer repair teacher (High school) I was able to solder together a simple beeper with a switch. This how-to gave me some tips on how to solder without burning the board like I did with the beeper. A suggestion for the future would be to give some direction as where to go next, like ideas for a beginner project or something that doesn’t involve special kits but stuff that can be bought at radio or something. Great Job again.

  10. I’ll second (third?) the Metcal love… until you’ve used one, you’ll wonder what could make an iron worth such a high price.

    Metcals use high-frequency switching for heating rather than pure DC resistive elements. This translates to almost instantaneous heat, extremely fast recovery, and the ability to load in the heat on larger components (like voltage regulators with large heat sink pads).

    For those questioning “what wattage”, that depends on the size of components you want to solder. A low-wattage iron does not necessarily equate to a lower temp. The higher the wattage, the more capable an iron is of “pouring” heat into an object without losing your set temp, such as those regulators I mentioned. My 50W ESD-safe Weller has done a commendable job on just about every SMD project I’ve done to date, but it falls face down when I have to solder heavy-gauge wire… it just doesn’t have the meat for it. The Metcal I use at work blows those types of joints away.

  11. Heh – I didn’t mean to disrespect the metcal’s. Almost every pro shop I know uses them because they are great. But, like you mentioned, they are quite expensive (though arguably worth the money). I wanted to recommend the Hakko as an inexpensive entry-level T/C station. It’s one that just about any hardware hacker can afford and will greatly improve their soldering experience.


  12. I just commented on the previous post, so I won’t replicate that here. But I would like to echo the sentiment of getting a temp-controlled iron. Check : They’ve got some really nice Xytronic irons. An analog one for $50 and one with a digital readout for $80. They both come with the copper-wool type cleaning stand.
    The best thing about a t/c iron is that your tip won’t oxidize so quickly. Even a 10W iron will heat up to 750-800F given enough time. An oxidized tip sucks at soldering.

  13. I am a Hakko 936 jockey and got one of their brass colored wire wool tip cleaners when I got the iron. Much better than a wet sponge at cleaning and it doesn’t cool down the tip when you wipe it. You can buy the same thing in the houseware dept. of your local store. Every few weeks I shake it over the garbage can and out comes all the solder – it doesn’t stick.

    I have also found foam drive bit holders with an adhesive back at my local hardware that are ideal for holding my assortment of tips to the side of the temp control. They were made to stick onto the side of a cordless drill.

    I live and work in a marine environment where the green fuzzies live and breed. For thru-hole boards I trim the soldered leads close to the board and then go back over with the iron and a touch of solder to create a small round mound of solder – no corrosion and nice and smooth without the normal micro-meathooks.

    For great control of the amount of solder I use the smallest diameter solder I can find.

    For SMT components I use the small end of a chop stick to hold the little buggers in place. You may want to carve it down a bit but leave the end flat and you can rotate the part into perfect alignment especially with a slight bit of beeswax on the end.

    Favorite anti-corrosion spray – Boeshield

  14. Actually, While metcals are expensive brand new you can often find them pretty cheap on eBay.

    I got one for $50 after a little watching and it’s in great condition. Well worth the money.

  15. I have a weller wtcp that was my dad’s in the 70s (still made by weller today). Sort of temperature controlled (you have to swap out tips), but, with small tips, I can do QFPs. _on an iron 30+ years old_

    I second everything y’all mentioned, but would like to suggest a few more tools needed especially for SMT work.
    – Tweezers – I’ve found the difference between $30+ and $3 tweezers to be minimal. especially when they are shared with other hackers – get extras, they “wear out” (some ME jacka** tries to tighten a bolt with them). I buy the streight and bent tip ones from digikey (i forget the manufacturer, if there is demand, I’ll look up the digikey #)
    – Quality flux – the pen is good, liquid flux is better. Kester no clean or water soluble is good.
    – Quality solder – kester 60/40 no clean, or water soluble – seriously, it will produce better joints.
    – Flux cleaner – worth every penny for cleaning off boards.
    – Isopropyl or ethyl alchohol – available at wallgreens/cvs etc – for cleaning boards, tweezers, reworked components.
    – Solder sucker – not for smt work, but great for through hole
    – Solder wick – getting expensive as the price of copper rises, but invaluable for smt work.
    – Magnifying visor – I have a busch and lomb one I got off ebay new for $20.
    – Quality flush cutters – $25 cutters are actually far far far superior to the cheap ones spend the cash, but protect them with your life!

    I actually have been teaching soldering to new members of our robotics team at GT. We went from through hole to reworking RAM DIMMs.

    With my setup, I can do down to 0.020 in pitch components. If there are viable leads, it can be soldered. What I am looking for is a good way to solder QFN (no leads) and BGAs. I have seen a few chinese hot air rework stations, but am unsure of their quality.



  16. As far as cleaning the tip of the iron, the wet sponge/paper towel is meant to cool the tip briefly. It’s called thermal shock and is intended to help reduce oxidation and should be done immediately before applying the tip to your work.

  17. Working with Weller Magnastats for several years I decided to go for cheaper ERSA equipment 2 years ago. The “entry-level” analog stations ( are a way good deal compared to Coopertools’ ridicoulus pricing for Magnastat irons. I use 0832SD and 0832PW long life tips and 60Sn38Pb2Cu solder which enhances the life of the tips by a factor or two.
    Pretty decent stuff, I use it also for smaller SMD work.

  18. For removing SMT ICs and components, your article is incomplete without mentioning “Chip Quik” – you apply their flux, then go over the soldered pins with the special solder. Once cool, the chip just ‘pops’ off. A bit of cleanup and you’re ready to place a new chip. AFAIK, this product is a unique solution to repair of surface mount components.

  19. You should be able to find denatured/isopropyl alcohol at even the small town hardware store. Last time I look the local store stocked only gallon cans and the sticker was a shock. Everclear isn’t cheap either, but a pint lasts me a long time. But no one will believe me when I tell them it’s only for critical cleaning purposes ;)

  20. I sent in a bunch of ideas for future “how-to” articles… ranging from basics like how to use o-scopes and meters, circuit diagram reading, planning PCB layouts and entry level microcontroller programming to working with FPGAs and analyzing data lines for reverse engineering purposes.

    Anyone else submit ideas?

  21. Another vote with #6 for 63/37 Sn/Pb solder. 60/40 solder solidifies gradually; any motion during the cool-down period can result in a “cold”, unreliable joint, and it can be difficult to tell when the solder has hardened completely. 63/37 is a eutectic alloy, having a very abrupt transition between liquid and solid when the cooling point is reached. It’s often specified for high-vibration work environments such as aircraft and military field use, where keeping the workpiece steady enough to produce a reliable joint is difficult. Situations where everything is floating in midair, e.g. under-dash car wiring, are much easier to handle with 63/37.

    Anybody can do good work with either type of solder, but 63/37 is probably friendlier to the novice who’s trying to figure out how to keep board, component, solder and iron positioned and steady with just two hands. It should be available at most of the same places selling 60/40.

    I also have to put in a plug for Radio Shack’s 45W desoldering iron: At $10-12 this thing is one of the best deals anywhere; quicker, cleaner and more controllable than inferior plunger-type solder-suckers costing about the same. The tips need to be replaced periodically, and the heat and motion can damage PCBs if you dwell too long, but it’s the most effective tool available unless you move up to a much more expensive professional vacuum desoldering station. Plus you can turn it into a hot-air soldering tool: (As reported on Hackaday at one point, although I can’t find the post.)

    A final note, precision tweezers and good flush diagonal cutters make a huge difference. Spend a little more now ($10 each) rather than making do with whatever you have sitting around. It’s totally worth it.

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.