FreeForm

Freeforming is a technique used to build circuits without using PCBs. Mark Tilden has used this technique, and it is used extensively in BEAM Robots.

Pros:

  • Small - Freeform circuits tend to allow you to squeeze components into a very small space.
  • Lightweight - Without the copper clad/stripboard and all of its stuff - you get a much lighter board
  • Cheap - You don’t need to buy boards, or PCB kits, or pay for expensive PCB prototyping
  • Quick - Again - without the need for prototyping, or planning matrix boards, it is a lot quicker to freeform

Cons:

  • Difficult - requires practice and good technique. You really need to be able to visualise.
  • Not easily maintained - you cannot easily replace a faulty component- make sure you test them first and take care when soldering.

Freeforming usually means taking the bare components, bending, trimming and soldering leads together.

What do you need

You will require a good Toolset including:

  • Decent soldering iron
  • Long nosed pliers
  • Wire cutters
  • Quick setting glue

Now - following our Safety Guide - you should also have the following:

  • Good surface/soldering mat
  • Goggles (this is where you are quite likely to have small bits of wire fly up and hit you in the face as you cut them)
  • Good lighting
  • No interruptions (burnt fingers are bad!)
  • Helping hands (the mini adjustable clamp variety) - to hold bits you don’t have enough hands for
  • MultiMeter - Try to ensure you have tested the components before you solder them in

You also need a lot of patience, and I seriously do not recommend doing this while tired.

Notes

t is also worth having a back of push in connectors. The reason for this is that you can freeform modules of circuits, and join them with jump wires. While this may add a little size and weight to a freeform, it will still be less than a PCB equivalent.

Planning a freeform

First be aware of the circuit you are using. Take each of the components, and judge the size and shape. Think about how many input/output connections the circuit needs. It is usually a good idea to have most IO connections facing the right way. Once you have all of these - then it is a matter of inspiration. For each idea, sketch it out (which is difficult because these tend to be more ‘3D’ than PCB circuits) and trace the pathways - make sure all the correct connections are there. Try to limit risks of leads that shouldn’t be touching accidentally doing so. This may mean glueing a piece of paper between them.