5. Bits/tips
Bits for soldering irons and guns are their essential parts. Depending on their shape, they can be used for varying purposes. Depending on material they're made of they have varying durability.
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| A transformer soldering gun with a soldering tip mounted and additional three tips next to it. |
People preferring using soldering guns often also make non-standard soldering bits depending on needs. For example twisting the wire and cutting it or even hammering it to form a bit resembling with its tip the truncated cylindrical, or even miniwave bits for heater soldering irons.
Similarly twisting two pieces of wire and cutting one off shorter and second only a slight bit to form a sharpened end, they form bits similar to screwdriver bits for heater soldering irons.
In my opinion it's a lot of additional work, but some seem to really like using those as I already wrote in a post about soldering tools ;P
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| Heater soldering iron bits (for Xytronic LF-369D): 1. A bit with 'miniwave'; 2-4 screwdriver bits 3,2mm, 2mm and 1,2mm; 5. Conical ballpoint bit. Descriptions in text. |
You can buy them in varying shapes, with different tips. The body/shaft of the bit should fit your soldering iron well - make sure you are buying a bit fitting really well with its dimensions to your iron - some owners of cheaper soldering irons buy soldering bits fitting their irons from more expensive brands, which usually work much better (better coating alloys give them much better lifespan, much better wetting characteristics etc.).
Bits shapes.
Conical ballpoint (number 5 on the picture) - as the name suggests it's a bit with a workpiece shaped as a cone, with slightly rounded tip. Some say that they can solder most components with such bit. It seems to me however that they aren't the most comfortable ones in use because of their round cross-section - due to this they have much smaller contact surface with soldered components and in the beginning they may be harder to use properly - they always need to have a sizable drop of solder on them to have a good thermal connection with soldered components. their thin tips however allow one to tin thin pads and lands for surface mount components.
This type bits are most often added to the soldering irons as a standard (except for the cheapest heater irons plugged directly into a mains socket which often have big, wide screwdriver shaped bits). If it isn't mentioned otherwise in a description in an internet sale - usually it will be such bit. If you're buying physically in a shop, you can check it easily of course ;)
I have such bit as indeed it was added to the soldering station as standard - it is pretty much a spare one for me in case I don't have a screwdriver shaped one because it got used up and I'm waiting for a new one.
Screwdriver bit - as in its name, the shape of its working tip resembles a screwdriver or a chisel.
They have various sizes. For soldering through-hole components, the ones with wider tip are better, thanks to that it's easier to heat up soldered components. Standard pads for through-hole components have around 3-4mm (sometimes less for smaller components), so similar width of the tip would be best. For the surface mount components on the other hand thinner tips would be much better, e.g. 1,2mm (it looks very similar to conical one, but the flattened tip helps it make better thermal connection with soldered components), which will allow you to solder of most the SMD components comfortably.
Wider, bigger bits could possibly be useful in case of soldering wider wires, or in general for parts with bigger thermal capacity. I however use a transformer soldering iron for that if my smaller soldering bits can't do it.
I have three (visible on the picture, 2-4) 1,2mm for SMD, 3,2mm for through-hole components and 2mm bit sitting in a drawer unused, ordered just in case, when I wasn't yet sure what bits I'll need. It's waiting until it'll be needed as a replacement or until I'll be soldering components with pads of such diameter.
Each of those bits for Xytronic brand soldering station did cost me 22PLN (~5,5EUR/7USD) bought at a popular online auction site.
Bit with miniwave (or microwave, but it's much harder to search in internet because of those pesky microwave ovens ;)
(bit number 1 on picture)
Its name comes from the fact that in its working principle it's quite similar to wave soldering used industrially for through-hole components where soldering is dependent on surface tension.
It's a cylindrical bit, truncated at the tip at around 45 degrees angle, with the truncation surface shaped specifically - usually slightly concave - so that on its surface, thanks to surface tension, could always easily form a drop of solder.
Thanks to this specific shape it is enough to place a components with many 'legs', like all those integrated circuits, microchips and such, and then move the soldering bit (and more precisely that solder drop on its tip) over the component's leads, and with a properly made circuit board and good soldering technique all the leads should be soldered easily without creating any shorts between them, or only with single bridges - easily removed with next swipe of the bit.
Unfortunately a complicated shape means that those bits are more expensive, but at the same time they're used more rarely - only for specific purposes (though you can solder with them components other than just those with multiple 'legs'), but they speed up work a lot, and thanks to shorter heating time they decrease risk of damaging the component being soldered.
Mine did cost 45PLN (~11EUR/14USD), so twice as much as other bits for this soldering station.
Cylindrical truncated bit - it's a cylindrical bit with its tip truncated at 45 degrees angle - similarly to the miniwave, but without that concave surface. That means that it has similar traits to the miniwave, but is much worse at that because it doesn't have such surface tension of solder like in the previous bit. I personally don't use it. Because of larger mass, so also larger heat capacity it can be useful for soldering bigger components requiring more heat for heating their volume up.
Some people owning a milling machine buy those bits instead of miniwave ones and work it to create the concave surface, to save some money - it is usually done by expense of the bit's durability (the outer surface extending bit's lifetime is destroyed in the process), however from their descriptions they have enough leftover durability for that to be economically sound.
Other bits - there are various bits with very wide tips or other strange shapes fit for soldering different integrated circuits and other specific components. I can't speak precisely about them, because I've never had to use one, but it seems to me that they are a sort of a relic of not so long ago, when hot air soldering stations were much more expensive and less available - today all that can be done faster with a miniwave bit or with the hot air. It could possibly be useful for more mass-producing kind of hand soldering (bit of heater soldering iron heats components being soldered/desoldered a bit faster than hot air).
Angular bits -for many soldering irons there are bits that have a longer shaft bent at 30 or 45 degrees angle. They have working tips with same shapes as above bits. They allow soldering in various places which are hard to access, thus they can be useful in repairing things - when you don't mount components according to size, just those that are needed. They aren't a good replacement for regular bits because being bent they are slightly less comfortable in use, however they can be a good addition. Because of them having a larger volume, thus also the thermal capacity - they may need longer time to be heated up, while at the same time they may allow one to solder thicker parts a bit easier.
Hot air stations nozzles - there are various shapes of those and some overlays fitted for specific kinds of integrated circuit packages (casings), which while using a suction tool attached to the chip allow for easy desoldering or soldering (without the suction holding tool). The standard are nozzles of varying diameters and round cross-section, chosen depending on the size of components being soldered, and on how much space there is around.
Nozzles for the hot air stations usually cost around 20-30PLN (4,9-7,3EUR/6,2-9,4USD), so it's worth to look sometimes just not at the price of hot air station you're buying, but also how many nozzles are there in that price ;)
Summing it up, for most uses in electronics, just 2-3 screwdriver shaped bits will be enough. If you add miniwave bit, and possibly some hot air nozzles to that, it should be enough most of the time for most uses.
In the next post about tools for desoldering and removing components ;)
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