• recklessengagement@lemmy.world
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    6 months ago

    What are the ideal iron temps for your typical solder? I have an old Weller system and I feel like my results are way too inconsistent.

    • jet@hackertalks.com
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      6 months ago

      Check the documentation for your soldering station, if your soldering station doesn’t have any documentation you can go with the melting point of the solder itself plus some overhead.

      But as illustrated below, it can get a little complicated, if you’re doing a lot of soldering with the same solder you’ll experiment and figure out what’s good for you

      Ideally you want to use the lowest temperature you can get away with, using too much temperature can potentially shorten the lifespan of your soldering tips, and potentially damage the printed circuit board.

      Get a testing board, any old board will do, and do some soldering and desoldering at different temperatures.

      https://kb.hakkousa.com/KnowledgebaseArticle10297.aspx

      lets look at the melting points of common solders:

      • Tin/Lead (Sn63/Pb37) - 183°C
      • SAC 305 (Sn/Ag3.0/Cu0.5) - 220°C
      • SN100 (Sn) - 232°C

      Now let’s add the 50°C we need for making a good soldering connection:

      • Tin/Lead: 183°C + 50°C = 233°C
      • SAC 305: 220°C + 50°C = 270°C
      • SN100: 232°C + 50°C = 282°C

      We now need to consider the type of soldering station we are using…Soldering Station which has very good performance, we should add approximately 100°C as the heat reserve for quick thermal recovery.  The resulting temperature settings are:

      • Tin/Lead: 233°C + 100°C = 333°C
      • SAC 305: 270°C + 100°C = 370°C
      • SN100:  282°C + 100°C = 382°C
    • weeeeum@lemmy.world
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      6 months ago

      Probably because it is a “dumb iron” with no thermal control. As soon as it touches anything it cools way down. Nowadays fortunately, cartridge tip irons are cheap if you’re willing to buy from China. Cartridge tips have the heating element and temp probe built directly into the tip, heat up and adjust extremely fast to thermal loads.

    • JamesNZ@lemmy.world
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      6 months ago

      As mentioned, you need the pad to be hot for the solder to wick onto it. There is missing info in step 1. Step 1 should say to have a slightly wet iron (solder on the iron). You used this molten solder as the heat transfer medium. Hold the iron so the wet solder on it is touching the pad and lead. This gives more surface area for the heat to travel from the iron to the pad. A dry iron touching a pad will have poor thermal connection, so the pad will take a long time to heat up.

      • TheOakTree@lemm.ee
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        6 months ago

        I think an apt comparison is touching hot stuff with a wet glove. With a dry glove, the heat has to conduct through the fabric before heating your hand. With a wet glove, the heat is conducting through the water and burning your hand. The solder, like the water in the wet glove, is a bridge for the iron to transfer heat efficiently to the pad.

        I think a lot of hobby soldering guides really neglect the idea of heat transfer and thermal mass.