I'm consistently getting poor solder joints that look dull and grainy rather than shiny. Cold soldering occurs when temperature isn't high enough or wrong tip is used - solder forms layers instead of homogeneous drops that break easily under load. Using a TS-100 at 350?C with 63/37 rosin core solder.

Temperature of 325-350?C is ideal for ESC and receiver wires to flight controller, with 400?C for battery pads involving larger amounts of solder. My technique: tin both surfaces, heat pad with iron tip, place wire, remove iron after 3-4 seconds.

Motors keep desoldering during crashes and I suspect it's my joints failing. Cold joints occur when solder hasn't fully melted or connected properly, causing intermittent power issues or complete component failure. What am I missing?

Use flux when soldering thicker gauge wire like battery leads and larger ESC leads - flux helps solder flow through the wire quicker. You're probably not using enough flux. Also try bumping temperature to 375?C.

Your iron tip might be oxidized or too small for the thermal mass you're trying to heat. For big soldering jobs, the solder joint can have larger thermal mass than the tip, sucking all heat from the tip as it melts. Try a larger chisel tip.

Avoid holding soldering iron on components for long - if wire isn't joined within 5 seconds, abort and let pad cool before trying again to prevent lifting solder pads. You might be rushing the process.