soldering

[CaptainCook]

I totally agree that clean copper is the key. I was introduced to no clean for rework about 10-12 years ago and yes, that's what is in most of the kits. It is also lead-free and complies with RoHS requirements (which hobbyist don't usually care about). I have also taken acid brushes and cut the bristles to scrub off old rosin with alcohol similar to you. It works great. The tip material in the flux pens is very stiff and also does a fine job of cleaning the old flux in lieu of a brush. I can actually get more scrubbing on the copper with a flux pen than I can with a brush. Although the pen is a bit more expensive. By using no-clean (or a water-soluable flux) both to wet the copper as well as in the solder the result will be a nice clean looking board with minimal residue that needs to be cleaned off the boards. If you decide to clean it that can be done by simply washing in water. It is very easy to remove. (The PCB assembly houses actually clean it off with water sprays in what looks like long dishwashing machines.)

I especially agree with you in spraying a non-conductive coating on your finished boards although I have not used Krylon for that purposes. All of the circuit boards that I make (or have made) are covered with a conformal coating made specifically for electronics. It is required for many uses (such as within the hospital/medical field). I have found this to be especially important in this crazy hobby we have. It provides VERY good protection from the inevitable rain/snow/moisture. I run my show rain or shine (I don't get snow here in Florida). One benchmark might be this: I have approximately 150 Xenon strobes that I opened and sprayed with conformal. Most of them I have been running for 6 years now. They all still work. Some have drip holes, some do not. You know the history of strobes from the various comments on these forums so I believe that proves that whether we use conformal or Krylon, the protection works. I even had a box with one of Greg's Rainbox Brains and a power supply in it last year. I sprayed the Rainbow Brain (not the RJ45s - very important). The box ended up submerged for about a week and in the end, the brain only needed some minor brushing of the two RJ45s whereas the power supply was dead and corroded.

[CaptainCook]

TechSpray has a good line of no-clean pens, solder as well as conformal coating spray. They are available at Mouser.com.

If you do decide to coat your boards, make absolutely sure that you do not coat any connectors, jumper pins, dip switches, etc. The coating is an insulator and they will not anymore. (My brother found that out upon return from his honeymoon - we coated all of the plugs on his lamp cords - but that's another story.)

Secondly, think ahead and be prepared for the day that you need to repair a board or replace a part. Get a conformal coating removal pen and maybe even a conformal coating dispensing pen to cover up after your repair work. I do not know if these will work with the Krylon clear spray.

The coating works great for me. We usually have 80-90% relative humidity during my July 4th show and although enclosed, my original 16 LOR units have never had a glitch due to moisture.

[Mike C.]

I wanted to thank you guys for clearing things up as far as cleaning the copper pads on the strips. My first (4) attempt(s) to solder a 4 pin male to male onto a strip was a disaster to say the least. I was wondering how they got those tiny little beads of solder on the strips. I was thinking to myself "man, it must take them forever". I went out to the local radio shack and pick out a set scrapping/cleaning tools and some rosin soldering flux. After some trial and error I figured it out and man what a difference it makes. The solder just flows on the copper pad, Thanks a bunch for the info.

[Santas Helper]

You can't be a Weller iron.

Drew

Who said they were a Weller iron?

Is it a new Halloween costume or something?