In my last post I introduced you to shopping safely and cheaply on eBay (which basically meant reading everything carefully and working smart with their search engine). Now with that groundwork over, here’s how to buy the tools and parts you need to work with electronics (and Arduinos) on eBay, including my own experience on what works and what doesn’t.

By the way, the list I’m working off of is taken from an excellent reference on building with microcontrollers, “Physical Computing”, by O’Sullivan and Igoe. While I’m still reading my way through it, it’s been a great introduction to using devices that let the microcontroller ‘sense’ the world. And although the book was written just before the Arduino became popular (and so the examples use other devices), the information adapts well to the Arduino, plus it’s a great introduction to electronics.

That said, here’s what I’ve found with eBay and parts, starting with tools:

Tools

Soldering Iron. I’ve used a cheap Radio Shack model for years, but have since switched over to a eBay version I found that I like a lot. Around $10, it’s an with a dial on the side. But if you plan to get into it in a big way, are considered quite good online; however a simple ‘pencil’ style iron will get you started. By the way, if you order one, order a with sponge at the same time; leaving your iron resting on anything else will soon give you (or your desk) a nasty burn.

Wire stripper or cutters. If you’re careful, a knife against the wire will do the job of removing insulation. But if not, there’s two kinds of wires stripper/cutters I’ve bought and used successfully – manual strippers (where you match the wire to the proper hole and pull) and automatic strippers (where you just insert and strip – quite cool, and easy to use). You can get on eBay via this link.

Multimeter. I’ve already blogged about buying a good multimeter (and which I’m quite happy with). However, if you don’t need all the bells and whistles, or are on a budget, you can get a super-cheap one that works fine for under $5 – just search on the models. Of course, don’t say I didn’t warn you when you want to upgrade to more features…

By the way, if you’re reading the shopping list that’s in “Physical Computing”, you’ll notice I left a lot of tools out, specifically a vise/third hand jig, glue gun, solder, needle-nose pliers, screwdrivers, and a toolbox. In my experience, you’ll find all these very cheap locally, cheaper than on eBay. For example, if you live near a Princess Auto (which Victoria BC has recently been blessed with), keep an eye on sales for many of these tools, as well as Canadian Tire. Recently, I picked up a metal vise for just over $8, and a hands-free jig for $2.50, both on sale at Princess. They are also fantastic for power tools, for example if you want to buy a hand drill, or a Dremel-style small drill for circuit board work.

That’s some of the tools for starting in electronics – now how about parts?

Electronic Components

Miscellaneous components. Resistors, capacitors, diodes, transistors, and so on. For components like this, there’s two ways to stock up: Buy individual packets of items (like 2.2k resistors, 22k resistors, etc.) or look for a group of components. For that, just add the word ‘lot’ to your search on eBay, like resistor lot/capacitor lot/diode lot/transistor lot (or use for all four together!) If you’re going the individual route, two companies I’m happy with are are and – even when I search for the lowest prices on parts, it seems 9 times out of 10 I end up placing an order with one of these two. Speedy, professional, and I haven’t had a problem yet. Start small, and once you’re happy, make regular orders to build up your stock.

Power supply. The Arduino plug is a female 2.1mm plug with center positive, so you want a power supply to fit that (as explained on their site). The modular ones (nicknamed “wall warts”) are handy for powering your Arduino when it’s not plugged in to the computer, but more importantly, for powering all the devices you’ve connected to it. For example, I have a for my motors. You need a beefy power supply for motors, and 2 amps means the motors have enough to run on (and gives me one less thing to wonder about when things don’t work!) 5v is what the Arduino uses, but the designers recommend 9v or 12v for external power, depending on what you’re doing with it.

Power connectors. Like my using Molex connectors for my stepper motors, a good connector can make it a lot easier to plug and unplug. I recommend checking eBay for “” – while not always needed, if you use an Arduino motor shield (which can use a separate power supply), your life will a lot simpler if you use a connector to bring the power in (I take two wires from the connector to the screw terminals of the board).

Headers. These little parts are the connectors found on the Arduino – male and female, and they make it convenient to plug in things. I recommend buying a selection of both , as well as the cables that fit in them (called ). Using these wires, you can breadboard from the Arduino to test out devices. One warning: While the headers may not be necessary right away, you’ll end up using lots and lots of jumper wires right off – so consider ordering a couple packs ASAP (and maybe one pack of the for times the gender of the header pins is reversed).

Shrink wrap tubing. I’ve found it a handy thing to buy on eBay, and quite cheap. Get a 2mm-3mm thickness of , and any color you want. You can usually get 3 feet or so for around a dollar. I just use a cheap cigarette lighter to heat the wrap and shrink it, and the result looks better to me than electrical tape – but of course, you may prefer the latter.

Breadboard. You plug a wire in, and connect it to the Arduino. These things are great for hooking up circuits. And while I’m not a fan of the cheap ones I’ve bought on eBay, you may find a better selection. If you do search online, I recommend you look for the quality , and get ones in shrink wrap, with terminals and a back plane – not only do they look better, but they are likely to be more professionally made. And while a bit more than the cheaper ones, they are still less expensive than most anything you’ll buy locally.

USB stuff. The Arduino has a port called an A socket, identical to most printers. To avoid plugging and unplugging, I’ve bought many a . I leave them plugged into the microcontroller, since a $1 cable’s wear and tear suits me better than an Arduino’s connector breaking! As well, I’d recommend a , so your computer’s USB is somewhat separated electrically from the Arduino “just in case” – get one with its own power supply, and you might even be able to run a few devices without using a wall wart.

Miscellaneous. It seems every tutorial I read ends up requiring something I’ll buy on eBay. – if you order in advance and buy extra, you’ll start amassing a small pile of stuff, which means your next project may have the parts all ready to go!

That covers just some of the tools and parts you’ll need – but there’s more. Turn in shortly for the third (and final) part, where I discuss the best Arduino deals on eBay!

I shop local when I can – but eBay frequently. Here in Victoria (BC, Canada) it’s hard to come by inexpensive electronics, especially Arduinos. Vancouver is just a ferry ride away, but I’m not into traveling for shopping – so it should come as no surprise I rely on eBay heavily for my components and electronics tools (who am I kidding – not just for them, but almost anything, from to to really nice ).

eBay however, can be an issue for a first timer – so here’s what I’ve picked up in the last decade so your every online shopping ‘trip’ is safe and straightforward – and a few tips for those times it isn’t…

• Join eBay ASAP. If you’re not a member, start there – it’s free and most importantly, it’s necessary in order to buy. There is a mind-numbing wealth of info to do this online, much of it on eBay’s own site (or just search on “how to shop ebay”), so I won’t cover it again here.
• Get Paypal. Technically, you can use your credit card at the PayPal link on any auction and pay that way, but I like Paypal for a lot of other uses – and you should too. The Personal account is the starting point: It’s fine for the occasional shopping on eBay, but eventually you will want a Premier or Business account (good news – you can have the Personal and one other account for those times you want to save a service charge or two). A PayPal account is the micro-payment solution they were looking for in the 1990s, and it’s the “gold standard” online for small payment transactions. It’s also especially useful if you want to sell things someday, be it on eBay or elsewhere.
• Learn to search right. Once in eBay, much of what you’ll find is related to how well you search. For example, if you type in “Arduino” you’ll find a wealth of topics. But you can pay a premium for that – so search for the Arduino part first, and use the new words you’ve picked up in that search to then find the same part w/o “Arduino” in the title. As an example, I just searched on “” versus “” – the lowest “Buy it now” price for each is $3.17 versus $2.44, which is about 30% more for searching with “Arduino”! This tip alone will save you quite a bit over time, since sellers understand Arduino users are more often than not hobbyists – and so willing to pay a bit more for their hobby.
• Take it seriously. While some people view eBay as a fun online store to browse, I like to think of it as a supplier of parts (OK, not all the time!) I have a separate User ID for shopping (to avoid mixing details of my shopping with my selling), and I keep track of the items coming in, leaving them quality feedback and in turn asking for it (feedback is the social ‘currency’ of eBay, if you will). It’s also important to take care to handle problems professionally. If you leave negative feedback, make it specific and to the crux of the problem, but make sure you try your best to contact the company first, since most are very eager to resolve things amicable. For example, when two out of ten of the linear bearings in an order were the wrong size, it just took a quick (and polite) email, and they shipped out two new ones at no charge. Problem solved – unless I had gotten mad and left negative feedback first. Keep emotions out of it, and you’ll likely have few problems – and for the rest, eBay has a resolution center to handle that, which likely means you’re protected if you used PayPal to pay (remember my tip on PayPal!)
• Start small. Risk $5, not $50. Order just a few things at first and try out the whole bid/win/pay/ship/receive/buy again loop slowly. Pay attention to the ratings on the seller for each auction (their feedback), and let that guide your shopping. You can also click through the Seller’s User ID link and look at the comments left from buyers, as well as frequently what items were sold. I use this not only to see where the seller has problems (for example, are they consistently selling shoddy products), but more importantly, have they sold that particular item before, and how did THOSE buyers feel? If you see an unusually low price, and the seller has just started selling that product, you might want to wait awhile – or consider a slightly higher price elsewhere.
• Read the auction carefully! You are agreeing to the terms, and have no one to blame if there are charges hidden in the text. For example, I once had my cable modem go belly up, and needed a replacement quick. At one auction, the price was good, so I bid. However, what I thought was a repeat of the shipping price ($5) in the auction listing was actually a second handling charge, and they got away with it – $10 instead of $5 on a $10 purchase! If I hadn’t been in a hurry and needed the modem, maybe I wouldn’t have been caught. Certainly, I’d never deal with them again. And while it is possible to have them cancel the auction afterwards (as a seller, I actually did this at a customer’s request once), you don’t want to get a reputation as a buyer who changes their mind.
• Remember eBay is not everything. For example, I will not buy electronic breadboards on eBay any more, after buying a couple that were very loose in the contacts. Likewise, I won’t buy a parachute(!), large capacity MicroSD cards (which are often sold as larger than they are) or very heavy items (the shipping is murder, unless you are fortunate to be in the same town, AND the auction allows local pickup in lieu of shipping). As well, there are times the local price is just too good, or Amazon is selling it cheaper, or something else, so you’ll just use them instead.
• Finally, be loyal. As you can imagine, this research can get time consuming – so when you have a successful transaction, bookmark the seller, and you’ll likely find you come back to them often. After all, a few cents saved means little if you need twenty minute’s research every time you want to shop from a new company!

I’ve used eBay both as a buyer and seller for over a decade, and find it a great place to shop. Give it a try, and who knows – you might end up buying an extra Arduino or two ‘cuz the prices are so good!

Part 2 covers parts every electronics wiz will need to buy, as well as my picks for buying online components and tools at bargain prices – read it here. As for Arduino-related parts, I discuss them in part 3.