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I started getting interested in drones recently and I bought a soldering iron last week on Amazon.co.uk

After using it for 5 minutes to try pre-tin some copper wires, the solder was unable to retain the lead on the tip, it would just fold its self and escape the iron. Also the iron apparently got so hot that it melted itself.

Can someone give me me some tips on what kind of soldering Iron I should use (please not very expensive hopefully up to £100) and how to actually take care of it so this doesn't happen again. I want to believe that this is not just my lack of experience but also a very poor quality soldering product that I bought.

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    \$\begingroup\$ Have you ever used a soldering iron before? \$\endgroup\$ – Eugene Sh. Dec 11 '17 at 14:59
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    \$\begingroup\$ If it gets so hot it melts itself then it's faulty, get it replaced. \$\endgroup\$ – Finbarr Dec 11 '17 at 14:59
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    \$\begingroup\$ we don't do product recommendations here. But if you search on the YouTube channels: "EEVBlog" or "Bigclive" they have some recommendations for you. \$\endgroup\$ – Bimpelrekkie Dec 11 '17 at 14:59
  • \$\begingroup\$ Did you use a solder with a flux core, or maybe some plumbing solder? (without flux.) \$\endgroup\$ – George Herold Dec 11 '17 at 15:04
  • \$\begingroup\$ If you have a budget for this of £100 you can easily find a decent temperature controlled iron. All I did was searched around for deals then before buying, I googled it to read reviews \$\endgroup\$ – MCG Dec 11 '17 at 15:16
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It's too hard to say what happened according to your description. The 5 minute thing might just be that the thin coat of solder on the tip oxidized, and therefore can't be wetted anymore with solder. That's normal, and the fix is normal tip maintenance.

The part about the iron melting itself makes no sense. Irons simply don't have enough power to melt themselves. One exception might be if this is a 115 V iron you somehow managed to plug into 230 V.

Get a real soldering iron, not something with questionable heritage you bought on price from the other end of the internet. Irons without temperature control just aren't worth whatever little you might pay for them. Not only do such irons overheat their tips, which causes them to wear out quickly, but they are terrible to learn good soldering with because the tip is always a mess. Then there is the issue of grossly over-heating sensitive parts.

Big clunky fixed-power 25 W soldering irons with four-facet pyramid tips were OK for soldering wires and resistor leads to tube socket eyelets back in the Pleistocene, but are of little value today.

Anything that is truly temperature-controlled (not fixed or with a "power" knob) is probably good enough for hobby uses. Check out the Weller WES51. Last I looked around, that was the cheapest soldering iron actually worth owning. They can be had here in the US for around $110. Look around.

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  • \$\begingroup\$ That was my first soldering iron! Still works 5 years later, decent bit of kit! When looking for a cheap first iron, I just looked for any deals going then google the model and read reviews. Best way to find a good bargain I found! \$\endgroup\$ – MCG Dec 11 '17 at 15:18
  • \$\begingroup\$ +1 for the Pleistocene, Or the days when every TV Repair Man had one of these in his holster amazon.com/Weller-8200-Universal-Soldering-Gun/dp/B00002N5LN \$\endgroup\$ – Trevor_G Dec 11 '17 at 15:20
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    \$\begingroup\$ @Trevor: Yeah, one of those got me thru college. Even back in the late 1970s it was already too klunky for most things. You got clever with it, like manual PWM to keep the temperature not too hot. I also ended up making my own tips from #10 copper wire. They wore out fast, but were dirt cheap to replace, which was important back when I was a student. I got a few feet of #10 wire as free scrap from some electrical job on campus. \$\endgroup\$ – Olin Lathrop Dec 11 '17 at 17:21
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You must keep your iron tip tinned from the first time you power it on. You need to apply solder all over the tip of the iron as it is heating up. This tinning of the iron tip prevents it from oxidizing and provides a surface that conducts heat better than the burned tin/copper that makes up the iron tip. If you do not tin the iron tip then you will get the exact issue you described at the start of your post. That issue is also accelerated if you have the temperature up too high. For most electronics you can get by with temperatures of less than 650 degrees Fahrenheit (~340 degrees Celsius). You may have to turn it up to 700 or (very rarely) 750 Fahrenheit (370-400 Celsius) for large metal pieces or RoHS solder but you must keep the tip clean and tinned.

As for the iron melting itself, it sounds like you may have a very poor-quality soldering iron, probably made in some won hung-lo Chinese factory (assuming you mean the handle actually melted). Buy a Weller or a Hakko. They are proven reputable manufacturers that build the finest equipment. My Weller is 25 years old and still works beautifully.

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    \$\begingroup\$ Yup, I keep my iron at 600F by default. That's fine for typical soldering of 0805 parts onto a PCB and the like. I turn it up to 650 or 700 as needed, which is sometimes for larger parts, but mostly for de-soldering. I don't remember having to go past 700F, but then I use tin/lead solder. \$\endgroup\$ – Olin Lathrop Dec 11 '17 at 17:27
  • \$\begingroup\$ @DerStorm8 Thanks for this reply. Is there something you could suggest to keep the iron clean? How often should I clean it? Also When you say apply tin on the tip, you mean all over it? \$\endgroup\$ – sfrj Dec 13 '17 at 14:00
  • \$\begingroup\$ @sfrj Generally all you need to keep the iron clean, once it's been tinned, is simply wipe it on a damp sponge or paper towel to wipe off the remaining flux residue every few minutes. They make special sponges that are designed for this purpose - I wouldn't recommend just any sponge because some of them could release toxic fumes. And yes, as the iron is heating up apply solder (with flux) all over the tip of the iron. The tin will help protect the iron tip from the flux residue, as well as provide a smooth surface that better promotes heat transfer and wetting of the solder \$\endgroup\$ – DerStrom8 Dec 13 '17 at 14:07
  • \$\begingroup\$ @DerStrom8 Ok I think I understand. But I am still a bit confused, sorry I am really new to soldering. So if I apply the Tin to the tip and then I use the solder and I wipe it into the sponge will the Tin come off? I have to apply tin all the time after soldering something? \$\endgroup\$ – sfrj Dec 13 '17 at 14:51
  • \$\begingroup\$ @sfrj First of all the tin is the solder. They are one and the same. Anyway, when you apply the solder as the iron is heating up with the flux it should flow onto the tip. When you then wipe it on the sponge it will leave only a thin, smooth layer of solder, or "tin", on the tip of the iron. It will not all come off. Then just wipe on the sponge every few minutes to keep the flux residue from staying on the tin too long and burning, and it will also help maintain the thin layer of solder on the tip. \$\endgroup\$ – DerStrom8 Dec 13 '17 at 15:04

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