This post outlines my favourite soldering iron, solder, and soldering related tools, and I will explain in great detail what kind of solder you should buy. Having the right equipment makes soldering and building FPV drones much more enjoyable.
New to soldering? I will show you all the basic soldering techniques in this tutorial.
Which Soldering Iron To Buy?
The Best Soldering Irons
I highly recommend the TS100, and that’s what I use daily! It’s affordable ($55), powerful (65W and adjustable temperature up to 450°C) and portable. It can be powered by a LiPo battery or power supply with DC12V-24V output. See my review of the TS-100 for detail.
The TS80P is a smaller version of the TS100, but with a USB-C connector, so you can use your powerbank to power it (9V/12V output). However it’s not as powerful as the TS100, with an output power of only 30W. See my review of the TS80P.
Here are some other decent soldering irons that come with power supply so you can plug straight into the wall socket.
|YiHua 908+||Cheapest basic soldering iron for the bench.||http://bit.ly/2hw3EQV|
|Weller WLC100||Another basic desktop iron, slightly better quality.||http://amzn.to/2vzEIlH|
|Hakko FX888||This would be my go-to iron for the bench if budget allows.||http://amzn.to/2xI8R1J|
What Makes a Good Soldering Iron?
You want to get a soldering iron that has the following features:
- adjustable temperature control
- maximum temperature of 400°C or even higher
- minimum power of 30W, preferably 60W or higher
Adjustable temperature allows you to handle works of different nature more accurately. Larger wires and soldering pads require more heat, while finer soldering requires lower temperature to avoid damage from overheat.
The wattage (power) of a soldering iron is an indication of how much heat it’s capable of producing. A higher wattage iron is usually better at “heavy duty” soldering, as it heats up faster with less temperature drop.
Soldering Iron Tips
You need steady hands, so don’t drink too much coffee before soldering :) This is a good tip, but what I really want to talk about here is the real tip for your soldering iron!
A good soldering iron can be fitted with tips of different shape and size. Pointy tips generally are better for precise soldering. Larger and wider tips are effective for bigger jobs.
I personally only use two tips for building and repairing FPV drones: a cone tip and a bevel tip.
I use a bevel tip most of the times because of its versatility. The large surface area helps to transfer heat faster, it’s especially helpful for larger jobs, such as soldering heavy gauge wire to an XT60 connector. The sharp edge is very handy for smaller jobs, which saves me time from having to change tips frequently.
For extremely fine soldering, like replacing micro surface mount components, or soldering tiny wires to a processor on a flight controller, the cone tip is great for that.
The TS100 already comes with a cone tip, so you just need to invest in a bevel tip (TS-BC2): http://bit.ly/2GY0vZi
The Best Solder
Using the right solder makes your whole soldering experience much more enjoyable! I recommend 0.6-0.8mm diameter solder for the fine work we do with FPV drones.
There are different types of solder for various purposes (different alloys and elements). My recommendation is rosin core 63/37.
If you can’t get your hands on 63/37, 60/40 (60% tin and 40% lead) is also very good.
Why 63/37 Solder?
When solder is heated up and melted, it takes time for it to return to solid. We call this period the plastic phase.
Movement in the solder joint during the plastic phase can create bad solder connections. Speaking from experience, this happens often when holding the wires or components by hand.
63/37 solder has a shorter plastic phase compared to 60/40 or lead-free solder, which means it solidifies more quickly, making it the superior option. If your soldering skills aren’t perfect, a shorter plastic phase can help improve the quality of your soldering joints.
There really isn’t any downside to 63/37 compared to 60/40, it is a little bit more expensive perhaps, but the price difference is negligible.
Rosin Core, Clean and No-Clean Solder Differences
I find “rosin core” easier to work with than “clean core” solder. Rosin core has more solder flux inside the solder than clean core, which helps prevent metal oxidation, especially for large gauge wires which aren’t tin plated.
However, rosin core solder can leave some “dirty” brown residue around the joints due to the larger amount of flux, this is easily removable with alcohol. This residue is not conductive anyway and should not affect your solder joints, so clean it or leave it, it’s up to you.
Clean core will not leave this residue, giving a shiny finish, but sacrifices the oxidization-removing property of the flux.
No Clean is similar to Rosin Core, and it basically means you don’t need to clean the solder joint as it should be safe to leave the residue on the solder joint.
Solder Wire Diameter
The soldering we do is usually quite fine and requires accuracy, therefore thinner solder wires are preferable. I personally use 0.032″ (0.81mm), anything over 1mm might be a little harder to do fine work with.
Avoid Unknown Vendors
It’s important to get solder from a reputable manufacturer / retailer, I learned my lesson the hard way: how the quality of solder impacts soldering quality.
Avoid cheap solder from eBay or Banggood, it is often of low quality.
Brands I have had good experience with are Kester and MG Chemical. Some also recommend Asahi but I have not tried it.
Good quality solder might be more expensive, but just for building and repairing multirotors, a single roll will last many years :) It is a worthy long term investment!
Solder Paste / Flux
What Soldering Flex to Buy?
- Kester Flux pen for general soldering: https://amzn.to/2tLWZbT
- Flux in a syringe for precise applications: http://amzn.to/2zo0WVC
- Solder Paste in a can: http://amzn.to/2sttBJj
What is Soldering Flux?
Flux is an acid or rosin based compound which helps with soldering. As the solder melts, the flux boils and flows to the outside of the molten solder, the heat activates the acid which removes impurities, manifesting as the “dirty” brown residue around the solder joint as mentioned earlier.
When metal is heated, oxidation occurs on the surface, preventing heat from being transferred effectively into the solder joint. When this happens, solder becomes pasty and sticky rather than fluid, making it much harder to work with. Flux helps by preventing oxidation, making the solder flow more easily.
How to Use Soldering Flux?
Adding flux to a metal surface before soldering can make it much easier to work with. Don’t worry if you apply too much, it is not electrically conductive and you can clean the residue off easily with rubbing alcohol.
If you have a dull and grey soldering joint, that’s usually caused by the flux completely boiling away. You can fix that by adding more flux to the joint and heating it up again.
Soldering Third Hand & Holder
A “third hand”, as known as “helping hand”, is a very handy tool (forgive the pun) for holding component steady while soldering. A third hand usually has at least two small alligator clips, and often features a magnifying glass to give you the best view of your work.
Some soldering iron holder comes with a couple of helping hands in a single unit.
- Banggood: https://bit.ly/3fcsrpU
- Amazon: http://amzn.to/2zp6YoZ
- Here is a review of the RealACC soldering helping hand (6 arms)
Pro Tip: Get some blu-tack as well, it’s useful for holding small stuff like wires and tiny components: https://amzn.to/3ebFTcr
There are times you want to remove solder from a joint or PCB (when you apply too much solder, or you want to remove a component or wire).
Common solder removers are “de-solder wick”, and “solder sucker”.
De-solder Wick acts like a sponge that absorbs molten solder, while solder sucker uses a small air vacuum to suck up molten solder out of a heated joint. If you don’t know what to get, I suggest getting the solder wick, as I’ve always found it more effective.
Or just get both in a bundle: https://amzn.to/3eqlBf5
Where to Buy?
- Brass tip cleaner on Amazon: http://amzn.to/2BlfxT7
- Brass coil tip cleaner on Banggood: http://bit.ly/2C4mXMc
- Solder Sponge on Banggood: http://bit.ly/2hQLUjQ
- Sponge on Amazon: http://amzn.to/2A72VBe
After working with your soldering iron for just a few minutes, you will begin to notice some black residue building up around the tip. Cleaning your soldering iron tip removes impurities and ensures the best possible performance. You should always keep the tip clean and shiny.
A cheap and common tip cleaner is “heat resistant sponge” that is designed specifically for soldering (wet with water before use). There is also “brass coil tip cleaner” which is more durable. Resist the urge to use a normal kitchen scourers – they are made of aluminium and will scratch and damage your tip.
Alcohol and Cotton Swabs
Alcohol is great for cleaning solder joints and removing residue after soldering.
Solder Smoke Extractor
Prolonged exposure to solder fumes can cause incurable asthma! To avoid breathing in fumes from soldering, get an activated exhaust extractor and work in a well ventilated area, or at the very least, use a fan to blow the smoke away.
Where to Buy?
If you like DIY like me, you can build a solder fume extractor quite cheaply and easily :)
Don’t want to burn your fingers when soldering wires? I use a pair of reverse tweezers. It’s really the best for holding small wires as they squeeze and hold on to the wire when you let go, it’s effortless.
Where to buy: https://amzn.to/2SE4R9r
- Mar 2019 – Article created
- Jul 2020 – Updated