I’ve been designing a 4-layer PCB for a product for a few months now and I finally got to the stage of assembling the prototype after the PCB and components arrived. Most of the passive components I used were 0603 surface mount parts so reflow soldering was the only viable option (if I wanted to maintain my sanity).

Since I don’t have a proper reflow oven, I decided to use the next best thing I own: No not my hot air rework station, a toaster oven!

There are, of course, plenty of guides and tutorials online for modifying a toaster oven for reflow soldering. They all involve a temperature PID loop to precisely control the heat profile for various solder types, components, etc,.

I really just wanted to see if I could just turn it on and see what happens. Spoiler Alert: It works.

I just preheated the toaster oven for a few minutes, stuck the PCB in there, and watched for the solder to start flowing. This took about 30 to 40 seconds. I wish there was more to this so I could do a more in-depth write-up but honestly that was it — nothing fancy and no precise timing or temperature profiles.

I gotta say, the final board is quite a beauty!

The Fine Print

Do this at your own risk! I did it because I’m just building a prototype and the final board will be professionally assembled. In addition, I know what I’m doing and I read the datasheets of all my critical components. You’ll notice that I did not put the electrolytic capacitor in the oven — I could not guarantee not to violate the very precise timings and temperatures specified in the datasheet. Also, please mind the fumes.

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I recently had to design a 4-layer PCB and I finally decided to give KiCad another try (after hearing great things about version 5). I’ve known about KiCad for years and even tried it once a few years back but it never felt quite “there” yet. After spending a few months designing a 4-layer board I have to say it has certainly won me over.

I had to design a fairly complex PCB that included a switching supply, high currents, plenty of thermal vias, high frequency traces, and some mixed-signal work so I was really curious to see what KiCad could do.

One of the most useful features in my opinion is the ability to easily view an interactive 3D rendering of the board with no additional setup. The ability to hide the soldermask and view just the copper layer in the 3D view is a great sanity check on top of the DRC.

Another really really really great feature of KiCad is the ability to easily import any 3D model as an STL or wrl file and visually align and scale it to a footprint. This feature coupled with a site like 3D Content Central that allows you find 3D models from virtually any supplier for free makes accurate PCB design really stress free.

Another underrated KiCad “feature” I have come to love is just how easy it is to move or copy components around in the schematic editor without having to hold down a mouse button. I think this feature, coupled with the convenient shortcuts, saved me quite a bit of time.

Based on this experience I think I’ll definitely stick with KiCad for PCB design until the single license cost for Altium becomes more reasonable. Expect a few detailed KiCad tutorials from me in the near future!

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