Solder joints - Page 1
Forum section: electronics / projects

author: Rohandn
author_rank: Newbie
timestamp: March 09, 2021, 06:10:49 pm
content: Hi I'm an amateur at soldering and I wanted your advice on the joints that I have soldered. Please let me know how I can improve the cleanliness of the board also.

author: bob91343
author_rank: Super Contributor
timestamp: March 09, 2021, 06:37:21 pm
content: You need more practice. They all look like cold solder joints. The dull, crusty look shows that. A proper joint will have a shiny, solid look. You need more heat or more prolonged heating or more flux. Just melting the solder isn't enough. It also seems that you are using too much solder.Of course one needs to be concerned over the possible overheating of the parts, and therein lies the most common issue. Too low an iron temperature is the culprit in many cases. If the tip is hot and tinned, it should allow correct solder temperature without overheating the components.

author: Benta
author_rank: Super Contributor
timestamp: March 09, 2021, 06:46:06 pm
content: Why are you using immensely fat wires for such a small board?Any way, the soldering iron is not there to melt the solder, it's there to heat the joint so the solder melts when applied to the joint. You could say: iron on one side of the joint, solder on the opposite side.

author: rfclown
author_rank: Frequent Contributor
timestamp: March 10, 2021, 01:48:19 am
content: Quote from: bob91343 on March 09, 2021, 06:37:21 pmUnless you are using lead free.

author: xrunner
author_rank: Super Contributor
timestamp: March 10, 2021, 01:51:45 am
content: Nothing to add to previous comments, but I would like to see the soldering equipment you are using.

author: coppercone2
author_rank: Super Contributor
timestamp: March 10, 2021, 07:14:06 am
content: sorry what I meant to say is, are the solder pads big enough for the AWG that you chose? Solder terminals are the chirstmas tree things.It looks a little tight there. I think you put a wire through the PCB and soldered another wire to that and it looks like a terminal.I would say the gauge of wire is much too high for that PCB, I can't see whats going on there.

author: jonpaul
author_rank: Super Contributor
timestamp: March 10, 2021, 02:32:41 pm
content: Hello: I have soldering my electronic stuff since the 1950s.What is the application current, power voltage, eg 12V auto, 10A 100 W amp, etc?1/ Beware that thick stranded wires often are hard to solder or tin due to oxidation or contamination of the plastic insulation. In that case we scrape the strands with xacto knife before soldering.2/ The PCB pads are a poor and unreliable method to attach such heavy guage wires, suggest thinner gauge wire or use a PCB with screw terminal connectors.3/ Best irons for large power work is Metcal. Our preffered iros are the old Hakko, 936 etc.4/ Use only high quality rosin core eutetic solder 63 tin/37 lead and NEVER use 60/40 or 50/50 or lead free. We use Kester.5/ A good mechanical bond to keep the wire from moving during cooldown is best, rather than just touching the wire and depending on the solder to hold it.THE SLIGHTEST MOVEMENT DURING COOLDOWN WILL CRYSTALIZE AND RUIN THE JOINT.Just the ramblings of an old retire EEKind Regards,Jon

author: coromonadalix
author_rank: Super Contributor
timestamp: March 10, 2021, 03:21:00 pm
content: Quote from: rfclown on March 10, 2021, 01:48:19 amDid you use some liquid flux ??

author: ajb
author_rank: Super Contributor
timestamp: March 10, 2021, 05:14:22 pm
content: Quote from: Benta on March 09, 2021, 06:46:06 pmThat looks like a flight controller for a quadcopter, so those big wires are likely the leads to the battery and the ESCs for the motors, which are typically fixed part of the ESCs and usually about that size from what I've seen.