Suppliers and Keeping a Stock Of Components#

Today was different and mainly involved ordering components from local electronics suppliers in the UK rather than China, where timelines are extended due to distance, and confidence in component authenticity becomes more important when you’re running a prototyping business rather than just dabbling in a hobby.

So why the move to UK suppliers for my business? I’ll speak plainly here:

  • I need to know that the parts are genuine.
  • The reliability of components is known.
  • I can resolve ordering or part issues quickly.

Is it more expensive? Regrettably, yes. But if something goes wrong, I can resolve issues quickly and I have a much greater degree of confidence that the parts supplied are genuine and will perform as expected.

To be clear, I’ve mostly had a positive experience with AliExpress and similar platforms, especially for prototyping parts. However, I have had the odd order go wrong, and trying to resolve it can be an issue. Problems I’ve encountered include:

  • Parts being mislabelled or presented as a brand-name product but actually being a “compatible” alternative that doesn’t behave quite as expected (annoying and can cost project time).
  • Parts being outright fraudulent and non-functioning (yes, that has happened).
  • Parts going missing in transit or not being sent at all.
  • Difficulty returning parts when something goes wrong (usually I just give up).

Where AliExpress Still Makes Sense#

Despite the above, I’m not abandoning AliExpress entirely—it still has its place.

I would typically use it for:

  • Breakout boards and dev modules
  • Passive components (resistors, capacitors, LEDs)
  • Connectors and generic hardware
  • Non-critical supporting parts

In short, anything where failure is inconvenient rather than costly.

Where I Don’t Take the Risk#

There are some categories where I’ve decided it’s simply not worth the gamble:

  • Microcontrollers and ICs
  • Power regulation components
  • Anything timing or signal critical
  • Components that are difficult to debug if they behave incorrectly
  • Anything that even remotely hits safety or compliance issues

If one of these parts is wrong, it can waste hours (or days) chasing problems that aren’t actually in your design.

Moving to Proper Suppliers#

For anything even remotely critical, I’m now leaning towards established suppliers such as:

  • RS Components
  • Farnell
  • Mouser Electronics
  • Digi-Key

These aren’t the cheapest options, but they are consistent—and consistency matters more than saving a few pounds when you’re trying to deliver something that works.

The difference is noticeable immediately:

  • Parts are traceable
  • Datasheets actually match what you receive
  • Delivery is predictable (often next day)
  • Support exists if something goes wrong

You’re not just buying components—you’re buying certainty and time.

Keeping a Stock of Components#

Another thing I’ve started doing is keeping a small working stock of commonly used parts.

Not everything—just the things that slow you down if you don’t have them.

My general rule of thumb is simple: if I’ve needed a part more than twice, I keep it in stock.

If you deal in the Analogue world more than Digital (where I tend to live at present), your regularly held stock will differ from mine, but the general principle remains the same.

At the moment my stock tends to consist of the following:

Always in Stock#

  • 100nF, 10µF, 47µF capacitors
  • Pull-up resistors (4.7k, 10k)
  • Smaller resistors (330 ohm, 470 ohm, 0 ohm links)
  • LEDs
  • A couple of known-good regulators (e.g. AP2114 or AM1117 series)
  • Resettable fuses (Helps stop the magic smoke being released!)
  • Signal Diodes, Zener Diodes and Schottky Diodes

Project Staples#

  • ESP32 modules
  • USB-C connectors
  • Headers and connectors
  • Common MOSFETs / level shifters

Order Per Project#

  • Sensors (e.g. BME280)
  • Specialised ICs
  • Anything expensive or niche

The goal isn’t to build a warehouse—it’s to remove friction. If I have to wait a week every time I forget a 10k resistor, I’m going to lose momentum very quickly.

Workshop Parts#

I also keep a small shelf of known-good parts (or at least parts where I understand their quirks).

Being able to grab something I trust and drop it straight into a circuit removes a huge amount of uncertainty when debugging.

A Simple Rule I’m Starting to Follow#

I’ve found myself applying a fairly simple rule:

If a part going wrong would cost me more than the price difference, I don’t buy it from AliExpress (I’d also include Amazon here, as many marketplace components are simply AliExpress parts stocked locally.)

Final Thoughts#

As with most things, it’s about balance.

Low-cost suppliers are incredibly useful and have their place, but once you move into building real prototypes—especially for other people—reliability starts to matter more than saving a few pounds.

At that point, sourcing stops being an afterthought and becomes part of the engineering process itself.

Time lost debugging a bad component is far more expensive than the component itself.

I run Protoworks (NI) in Northern Ireland, helping small businesses design prototypes and build custom software. If you have a hardware or software idea you’d like to sketch out, feel free to get in touch.