For an electronics project with some kids i needed a platform to built with the ESP32. So I came up with this version:

• big enough to fit two MB-102 boards (63 pins long)
• If you place the ESP32-dev board in the middle, you have 3 pins left on every pin row
• there are 2 banana plug posts to connect quickly with the power source. So the whole project can be stored easily and finished on an other day.
• fixed cables from the posts, which can be used to power the design everywhere on the board

Parts needed

Breadboards

The breadboard needs to have 63 pins in one row. It is often described as 830 pins or MB-102. The size is 164x55 mm. You need two of them.

I bought this kit here, as it comes together with cables. Especially in the 5er kit is has a comparable price as you get 15 boards together with 120 cables m2m + 120x f2m + 120x f2f. Enough to make 7 boards: https://www.az-delivery.de/products/3x-breadboard-3x-jumper-wire

You have to seperate the power rails on both sides of the bread boards. Then cut of all protruding connectors with a sharp knife. Take care and do not cut yourself! Also make sure, that the sticky paper on the backside is flush with the sides, as there is a tight fit in the holder.
I could have considered these connectors in my design so they wouldn't need to be cut off, but I wanted the have a clean optic.

Banana plug posts

Most power supplys have 4 mm banana plugs connectors. So these are used here to.
You need some with 4 mm thread and with similar size, otherwise they will not fit and protrude on the underside.

I bought these here as they come in a nice 5er pack and these ones do have a hole, so you can clamp a wire also: https://de.aliexpress.com/item/1005004349139194.html

Cables

I recomend a red and black cable with around 20 to 25 cm, depending on your likings.

You may have to redrill the holes depending on the exact diameter of your cable. My cables do have an outer diameter of 2 mm.

You can solder them to the posts, or use some crimped-on terminals as I did.
At the other end I soldered a single pin header and isolated it with a piece of heat shrinking tube.

Printing

Print the Holder and a Cover.

I used PETG, as this not likely to break easily. For printing nothing special:

• 0,4 mm nozzle
• 0,2 mm layer height
• 3 walls
• 15% Gyroid infill

The cover is just to slide in and will stay in place just by friction. You can jank it out again with a screw driver.

By the way: The color is “PETG - Transparent Green” from FilamentPM