Soldering Iron Tip Saver. Beginner’s Trial 13

Most of the Soldering iron Tips or Bits now available are Copper core surrounded by Iron . It is coated with Nickel or Chromium to prevent the sticking of solder. If we are switched on the soldering iron for long period, the excess heat may damage it permanently. If the soldering work is intermittent, it is ideal to keep the tip half warm. This circuit performs this function. It has a switch and if it is in the Off position, the soldering iron tip remains half warm and if the switch is in the On position, within seconds, it will become fully heated. Don’t be confused. Not a large circuit, but a single diode is sufficient.

See how it is working. You know that the 230 volt AC cycles with positive half and negative half cycles. When we give AC to an electric device, it works through both the half cycles of AC. Look the diagram below.

AC switch is there in the Phase line going to the Soldering Iron. It is bypassed by the diode IN4007. The AC switch is doing the trick. When it is in the ON position, the current passes directly to the soldering iron, so it will warm as usual. When the switch is in the Off position, current passes through the diode only and the soldering iron gets only half cycle. So the iron remains half warm.

If you are giving a rest to the soldering job, then keep the switch in the Off position  The soldering iron will remain half heated so when the switch is in the On position, it will become fully heated within seconds. By observing the brightness of the LED you can confirm it.

Caution: The circuit uses AC, so there will be lethal shock if any part is touched. So do not try this if you are not experienced in handling AC circuits. You may seek the assistance of a well experienced person to make the arrangement.

4 responses to “Soldering Iron Tip Saver. Beginner’s Trial 13

  1. Hi,
    ഇത് വളരെ പ്രയോജനപ്രദമായ ഒരു സർക്യൂട്ട് തന്നെ. കുറേ നാൾ മുൻപ് ഇത് കിട്ടിയിരുന്നെങ്കിൽ ഒരു അയൺ കളയാതെ കഴിക്കാമായിരുന്നു. ഇനി വാങ്ങുന്ന അയണിന് തീർച്ചയായും ഈ സർക്യൂട്ടിന്റെ പരിരക്ഷ നൽകണം. സർക്യൂട്ടിനു നന്ദി.

  2. Dear Sir
    Thanks for your valuable feedback and suggestions. I am trying to share the simple tips and tricks which I have learned from technicians ( not well educated) . I using an old porceline Fuse carrier as a heat sink to keep the Iron.Another method is to wrap some winding of thick copper wire on the Iron while soldering heat sensitive components.DR 25 diode you mentioned is the big sized germanium diode once used in Radios but not available now. It is a very good heat sensor. I have procured it from a shop to see how it is working.

  3. Dear DMK,
    You made me remember my practices in good old days, when I was a student of the VS Rajagopal Radio Institute, near TVS, Annasalai, Madras (Chennai). I do not emember my principal’s name, but he told us the trick, to use the then availabvle DR25 opr the selenium plated diode. One of our inmates made a small M shapped stand ffor keeping the hot tip of the soldering rod. We were forced to use small tip by wrapping a thick copper rod on the then available 35W bulky soldering rods to solder very thin PCB layers. BUT, THE EXTRA LED is an added use here, which we were un-aware of. Thank you very much sir!