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Basic Tools and Hardware

Getting started in electronics doesn't necessarily mean spending thousands of euros before you can accomplish anything interesting. While there are a number of very useful tools that can cost hundreds or thousands of euros, we've tried to set out here the basic tools that we think are a good starting point for anyone interested in creating prototypes or even manufacturing on a micro scale (keeping in mind that not everyone has 5000€ set aside to build a basic electronics lab).

All of the tools on this page are aimed at Surface Mount Technology (SMT). The reason for this is that anything except the simplest devices will probably be easier and cheaper to manufacture with surface-mount components, and you'll be better served by setting up a solid manufacturing workflow from the start. As such, much of the content on this site focuses on 'reflow soldering' (where solder paste is applied to the printed circuit board and 'melted' in an oven).  It's entirely possible to solder SMT parts with traditional hand-soldering (other than BGA parts since the pads are 'underneath' the chip), and we often do so when prototyping, but you probably only want to do this where it's really necessary (such as soldering through-hole header pins), or when making one-off prototypes.

Hand Tools

Tweezers

Probably one of the first and most useful tools you'll need to buy is a high-quality set of non-magnetic ESD safe tweezers. You'll need these to easily (and safely) pick up and manipulate tiny SMT parts and populate your circuit boards, or work with SMT components in general. Thankfully, it's also one of the least expensive tools you're likely to buy. The two main shapes of tweezers used when picking up and handling components are 'straight' or 'curved' edged. It's really a matter of personal preference which shape you prefer (personally, I find the curved tips easier to work with). While you are free to shop around, we do offer some inexpensive tweezers in our online store (straight, curved) that are are easy to work with, have very fine tips, and have an excellent build quality for the price.

 

Pliers and Wire Cutters

These are easily found in any hardware store, but pliers and wire cutters come in handy when prototyping, whether to snap off header pin, trim cables, etc. Any good quality pair should be fine.

Rework Tools

While not 'essential' (you may be able to get by with just some tweezers), some simple tools for poking, prodding and pushing ICs around can be very useful, especially when you are trying to remove components from a soldered board using a hot air gun (see 'solder station' below) or precisely adjust the position of a small component. Some common and useful types of rework tools can be seen below. A quick search on ebay for something like 'soldering tools' should produce several sets for 10€ or less.

Meter

A basic multi-meter is something you'll use throughout the entire development process, whether in prototyping or later in quality-control. Any 20€ meter should be fine, though in the case of surface mount soldering you might want to purchase a unit that also measures temperature (to 300°C or more) since this can be useful to test the temperature of your reflow oven when working with solder paste. Check that the meter also has a Diode test function (most do), since you can use this to determine the polarity of LEDs if you don't know which side is + and which is - (it's much quicker than searching through the datasheet).  Simply connect the two probes on the meter to the LED terminals and if it lights up (however dimly) you've found your LED's polarity.

Soldering/Rework Station

Despite the fact that we focus on surface mount parts, a good adjustable temperature soldering station is absolutely essential. It's something you'll use on a regular basis -- especially in the important prototyping stage -- so it's important to make the right choice at the beginning to avoid wasting money in the long term by replacing an inappropriate (or useless) product down the road. There's really no alternative here: If you're serious about electronics, you need a decent quality adjustable soldering station where you can control the temperature up to about 400-450°C, and where you can change the soldering tips. Unfortunately, this will set you back at least 100€, but there's no real alternative in the long run. If you can afford to pay a little bit extra, you'll be better off buying a unit that also has a hotair rework gun built into it (you use this to repair PCBs and remove faulty or poorly soldered components). While we'd recommend buying a station from a known manufacturer such as Hakko if you have the possibility, if you're on a budget Ebay is a good source for less expensive Chinese imitations of soldering stations similar to those made by Hakko and other manufacturers (see the example photo below for a unit that has both hot air rework and a normal soldering iron in one small package).

Soldering Tips

Just as important as the soldering station are the soldering tips available for it. The reason that you need to choose a good soldering station is that you want to be certain you can use a variety of different soldering 'tips' with it depending on the components you're working with. Manufacturers like Hakko offer tips in dozens of different shapes and sizes, but the two most useful shapes for surface mount work (in our opinion) are a small conical tip, and one medium 'wave' soldering tip (which is conical in shape, but with a flat surface on one side). Resist the temptation to buy the smallest tip you can find (0.1mm, etc.) ... they're useless 99% of the time, and they solder very poorly because you need a certain amount of surface area to produce enough heat for the solder to reflow. A soldering tip like the 900M-T-B works well for both through-hole and surface-mount parts down to 0603, and will be appropriate for 95% of your soldering work. The wave soldering tip (such as the 900M-T-2C) is used to 'wave' solder QFP or other fine-pitch components. Essentially, you use this tip to 'drag' a bit of solder across the pads, and the solder will naturally bead to the pads thanks to the solder resist on any professionally produced PCB. If you are ordering the tips from an online source, you may want to order a few tips because they eventually wear out and you may not be able to easily locate a source for tips for your iron in the future if it is off brand.

 

Flux Pen

While flux (or a flux pen) isn't technically a 'tool', per se, it is an essential part of surface-mount soldering. You can purchase flux in either a liquid form in a bottle or in flux 'pens' (basically a highlighter filled with flux rather than fluorescent coloured ink). The pens are probably more convenient since you don't have to worry about spills -- flux is both flammible and sticky, and likely isn't very good for you to get all over yourself or your work area.

Flux helps solder to reflow and makes working with surface-mount parts much easier. Before soldering an IC to bare pads, you should make sure the pads are clean (clean them with some Isopropanol/alcohol if necessary), apply flux to the pads with the flux pen, and then solder the parts. When doing rework (removing chips or fixing a solder bridge, etc.) apply some flux before you try to reflow the solder ... you'll have a much easier time than if you weren't using any flux.

While there are probably hundreds of different types of flux, the one we tend to use ourselves is Kester #2331-zx. It's water-soluble, meaning it can easily be washed off with water and a few gentle strokes from a soft tooth-brush (unlike some flux formulations that we've tried that stick like super-glue). You're free, of course, to try any other manufacturer or model, but a bit of flux will almost certainly make life easier when working with surface-mount parts, and it's well worth adding one or two flux pens to your basic kit.

Reflow Oven (when working with solder paste)

You may not need this right away (you can definately get by with hand-soldering for one-off prototypes), but if you get more serious about electronics and intend to produce more than one or two boards of the same design, you'll be better served using solder paste and will need a way to efficiently cause it to reflow (i.e., "melt").

While specialised ovens exist for this purpose (with appropriately elevated prices and sizes), for small scale manufacturing a simple 50€ 1500-2000W toaster oven with manual controls can be turned into a more than capable reflow oven. We've seen numerous adapters on the web and on EBay, but we've had perfect results with the (very convenient) kit offered at Reflow Kit. It's a bit expensive, but it's dependable, easy to adjust (you can modify all the settings over a simple serial connection), and we were genuinely surprised by it's accuracy and 'repeatability'. (The only caveat is that the default temperature on the device was too low for us, and we had to set the peak reflow temperature to around 245°C to get lead-free solder paste to properly reflow ... the default is around 230°C which is much to low).

The device works by controlling the amount of electrical current flowing into the toaster oven (the oven is plugged into the controller, and the controller is plugged into the wall).  You place the attached temperature sensor inside the oven, which is used to determine how much power should be applied and for what duration. We tested the accuracy of the device with another temperature meter, and were genuinely impressed when the temperatures were consistently within 1-2°C of the target. Any basic toaster oven with manual controls (and sufficient power) should work, but we found the toaster oven also sold by Reflow Kit, a Severin TO 2020, worked admirably for the price. It's a "no-frills" oven, and the door is conveniently designed in a way that prevents any damage to the temperature sensor cable.  For the temperature sensor itself, we recommend attaching it so that it is in contact with the surface of a spare PCB to make sure you are measuring the PCB surface temperature and not the air temperature.  You can see a photo of how we've done this ourselves (using high-temperature Kapton tape) below:

 

Microscope

This is a tough one. A good microscope is absolutely invaluable when working with surface-mount parts, soldering fine pitch components, inspecting soldered pads, etc., but it will also set you back between 300-600€ for an appropriate, decent quality unit with the right accessories. If you are planning on doing any sort of manufacturing it's essential since it's the only way to inspect your boards (without going blind), but if you're just testing the waters it's understandably difficult to justify spending so much money on one item. If you're serious about electronics, it's the best 450€ or so that you're going to spend, but inexpensive 'helping-hands' may get you buy until you have a bit more money to invest, or until you're convinced that electronics is something you really wish to pursue.

If you are able to invest the money in a good microscope, though, here are some things to keep in mind when deciding on which unit to purchase:

1. Somewhere from 10x to 40x magnification is ideal for surface-mount electronics.  (We use modified 20x/40x units ourselves giving 10x/20x magnification.  10x is ideal for general work, and 20x is perfect for inspecting individual pads or for very small parts.)
2. You'll want a 'stereo' microscope for ideal working/viewing conditions, and you may want to consider a 'trinocular' design for a few euros more.  With an appropriate adapter the third tube allows you to add a still or video camera, which can be useful for documenting your work or showing other people the results of your inspection, etc. 
3. You want the largest possible working distance between the object and the lens to allow you to freely move objects or place the soldering iron (4" or more is ideal, 8" is great).
4. The ability to illuminate the objects is very helpful (via a ring-light adapter, etc.).
5. You'll want to purchase microscope on a solid boom stand to allow you to freely move the unit around and have the maximum possible work space.
6. If available, you may want to consider purchasing a 0.5x "Barlow Lens" for the microscope. This effectively doubles your working distance (from 4" to 8", for example), and halves the magnification (from 20x to 10x). We've fitted 0.5x barlows on all of our 20x/40x microscopes, and find the resulting 8" working distance and 10x/20x magnification perfect for the kind of work we do.

There are a few reputable dealers for microscopes on the Internet (search on Ebay for terms like "stereo microscope boom" for the microscope, "barlow 0.5x" for the barlow lense, etc.).  If you purchase everything from one reseller you can probably negotiate a lower shipping rate. We purchased some of our microscopes off Ebay and use the 20x/40x stereo trinocular models on a boom stand, with a ring light attachment and a 0.5x Barlow, and were pleasantly surprised with the build quality (and the weight, ouch!) of the units we purchased.

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