The cam toys are probably the simplest category of mechanical toys and not at all as attractive as the wind up toys for example. Still the cam toys have a lot of fans - probably because they are cheap, easy to make if you want to make one yourself and have great retro-look.
Not all cam toys are that simple though. Some of them include a large number of cams which can power many cam followers and thus create quite a complex movement.
But maybe you first need to know what a cam is?
What exactly is a cam toy
You can see an example of a simple cam toy on the picture. The toy works with at least one cam which is basically a circle (or square) of wood, plastic or metal attached to a crank which makes the simplest cam toys very similar to the crank toys. Typically the circle is attached to the crank not exactly in its center. This causes
which can produce the effect that cam toys are looking for. You can see that on the picture - the cam is rotating around the "X" mark, while the real center of the circle is far away from the rotation point.
Most often the cam follower is supported by a wooden or metal block which prevents it from falling from side to side and keeps it moving only vertically.
If in a cam toy there are arranged 2,3 or more cams placed in different locations and attitudes, it can achieve quite comples movements. For example I have seen a
big cam toy worm
moving with awesome realism - that was possible due to 6 cams placed under the worm body.
Collecting cam toys
Collecting cam toys is popular within creative persons. They are great for inquisitive kids and teens because the simple mechanisms are very easy to study and understand, yet at the same time these toys are very elegant.
Collecting cam toys is not at all expensive or hard - the toys are cheap and best of all, simple enough to make them yourself.
Making cam toys yourself
Most self-made cam toys are made of wood. Creating a cam, follower and some simple shape like the chicken we have on the animation above isn't a rocket science.
You need some very basic tools
like a fine saw and a file. The cam toy needs to be painted in order to look attractive.
When making cam toys there are just few very important things to watch for:
- The cam, the follower and the support slides must be smooth enough (use the file to smooth them if you are making a wooden cam toy).
- Put the support slides close to each other - they should allow the cam follower move horizontally.
- Make the bottom of the follower wide enough so it doesn't jam at the edge positions. You can attach a small lath to it to ensure the cam always touches the follower.
We are going to publish some visual guides about making specific cam toys on this web site pretty soon. But if you want to learn more right now, I recommend you checking Making Mechanical Toys - an excellent illustrated book explaining the magic of mechanical toys, including the cam toys we are talking about.