Real PCBs have curves! ;-)

[Axtman]

I have repaired a lot of amps from various eras. This occured to me while working on an old Peavey mixer. When didamp manufacturers switch over from curvy PCB traces to straight lines?

If I were to guess I would say mid 1980's is when they switched to straight lines.

[Enzo]

Probably when they started using software for the graphics. Old boards were hand drawn. But I wouldn't say it was cut and dried.

[Chuck H]

OSH Park, a small-ish PCB fabricator and specialists in prototyping actually offer software to get the curvy, old school look on your PCB's. Which is silly I think. But hey, give 'em what they want. Right? The boutique pedal board market may benefit from that sort of thing.

[nevetslab]

Before the days of software-driven PCB layout, we all did it from hand-drawn grid line vellum for the pattern, then did the tape-ups on semitransparent mylar on a light table. 2:1 format is what I used, not having the need for higher resolution. Bishop Graphics had loads of pre-formed corners and bent-lines for a variety of tape widths. Often curves developed when routing around large cutouts for a toroidal power xfmr in the package, or needing to get around some other chassis-based items. It was easy to lay down straight traces, as it was curves. Many layout artists didn't bother with the pre-cut corners and such, and just bent the crepe-adhesive backed tape used for the trace patterns. I've done it both ways over the years. There was something very satisfying working on a large board layout at 2:1 over the warm surface of a light table. Back then, the silk screen layer was done in pen-and-ink using a drafting machine, Leroy Lettering templates and technical pens. Loads easier in the software-driven format, but there was something very satisfying in the older method.

[Enzo]

Oh wow, I forgot about Leroy Lettering sets. We used those in my drafting classes back in the ancient days of my schooling. Cool.

[tedmich]

OSH Park, a small-ish PCB fabricator and specialists in prototyping actually offer software to get the curvy, old school look on your PCB's. Which is silly I think. But hey, give 'em what they want. Right? The boutique pedal board market may benefit from that sort of thing.

electrons prefer to flow in smooth curves, not harsh angles, it degrades the TONE.

Argh! Was I channeling the spirit to Howard Dumble again? 3rd time this week...

[Chuck H]

Ah. It's not the PCB maker (OSH Park) but a plug in offered by an open source PCB design platform (KiCad).

https://hackaday.com/2022/04/17/kica...handmade-look/

[Mick Bailey]

Over the years I've seen a few amps with curvy traces and with the components soldered to the copper side. The last time was a Sundown combo (stuffed in the back with Denis Kager's hand-written notes on all kinds of stuff). I thought it looked like the same manufacturing process as some early PCB TV sets. Dead easy to trace the circuit.

[Greg Robinson]

Kicad 6 now has some limited curved trace and/or teardrop fillet? functions built-in. I haven't really explored the feature yet, a quick mess around now it seems rather unintuitive. Might explore that plugin when I've got some spare time.