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I have a very fine PCB (illustrated in an answer to Soldering with a delicate looking board) but I have discovered that the screwdriver like tip I have seems to be too clumsy to clear solder from so tiny a hole.

If I go and buy an alternative tip what am I looking for?

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  • \$\begingroup\$ What soldering iron are you using? What difficult components are you soldering? SC70s? QFNs? Smaller pins means smaller tips, it's that simple! \$\endgroup\$ – ACD Sep 12 '14 at 17:00
  • \$\begingroup\$ go for a 0.3mm conical tip - should work for anything you end up doing. make sure to look after it though, and never push too hard. \$\endgroup\$ – KyranF Sep 12 '14 at 17:19
  • \$\begingroup\$ Stuff the soldering iron and go for a reflow workstation? Much better than a soldering iron for small SMD work obviously, but can melt things if you're not careful ;) \$\endgroup\$ – Majenko Sep 12 '14 at 22:56
  • \$\begingroup\$ I've never been a fan of conical tips and prefer the ones it sounds like you have but you can get them down to small sizes for some irons, as in a millimeter or so. \$\endgroup\$ – PeterJ Sep 13 '14 at 3:17
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Firstly, "very fine" is quite subjective when it comes to PCBs. However, the picture you point to
board in question
seems to look like components around the 1206 or 0805 size, so I'll answer based on that basis.

Different tips can work well for this size of component depending on the operator and what other tools available. However for a general hobbyist, the a conical (or B series/type) tip with a width of around 0.5 mm to 1.0 mm width is probably the best investment as it will work for most components around this size.

Examples of that type of tip for sale for different soldering iron types can be found with this Farnell UK search. Similar will be available from other element14 countries and other suppliers.

This article Use for different soldering iron tips gives a pretty good round-up of the common tips available and is definitely worth a read.

I'd also say that a fine pair of tweezers to hold components still, a magnifying glass to check the joints and always keeping your tip clear are as important as the tip you use.

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    \$\begingroup\$ I also recommend a brass wool ball for cleaning your tip. \$\endgroup\$ – tcrosley Sep 12 '14 at 18:27
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It's more than just about the size of the soldering tip. Certainly, as you scale in component size you need smaller soldering tips. The main problem with this however that is that as the tips scales the ability to get heat into the tip and its thermal mass also drops. In an ideal world you really want to have a whisper thin temperature stable soldering tip.

There are a series of precise and very well temperature controlled soldering irons like the MetCal style that work on the skin effect. They deliver the electrical energy to the outer layer of the tip and as a result the outer skin of the tip heats up much more rapidly than trying to heat up the whole mass of the tip. It also places the heat precisely in the zones that can be controlled.

Unfortunately these do tend to be very expensive or much more expensive. But they are well worth the investment especially if you're doing and soldering of SMD. If you're doing this professionally it is worth the investment.

{Note: I do not and have never worked for MetCal I have only used their equipment}

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  • \$\begingroup\$ RadioShack has a digital temperature controlled soldering iron for $90. \$\endgroup\$ – tcrosley Sep 12 '14 at 18:31
  • \$\begingroup\$ @tcrosley very interesting. Do you know that uses the similar or same technology as I described or is it just a very fine tip? \$\endgroup\$ – placeholder Sep 12 '14 at 18:37
  • \$\begingroup\$ I have no idea if it uses the skin effect as you describe. It seems to heat up very fast and hold the temperature to whatever is set on the display. Obviously not a MetCal, but for the money much much better than the typical 30 or 40w soldering iron used by so many hobbyists. I use a Weller WD 1 at work and like the RS one I have at home just as much. \$\endgroup\$ – tcrosley Sep 12 '14 at 21:11

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