Each shaft (except the green one, which is too short) has a square cross shaped crosssection over much of its length. Connectors can be clipped to the shaft anywhere along this segment of the shaft.
Each blue spacer ring is half the thickness of a connector.
I've also seen a gray spacer which is equivalent to three blue spacers, but I don't own one and have not found them on the K'NEX mail order form.
| shaft | length in units of blue spacers |
|---|---|
| green | 0 |
| white | 6 |
| blue | 12 |
| yellow | 22 |
| red | 36 |
| gray | 56 |
By knowing the length of a shaft in terms of how many connectors can be arranged along its length, and the thicknesses of various gears and pulleys, we can determine how to arrange gears, pulleys, connectors and spacers along a shaft.
| component | thickness in units of blue spacers |
|---|---|
| small gear (blue) | 4 |
| medium gear (red) | 4 |
| large gear (yellow) | 3 |
| large pulley | 4 |
| small pulley | 2 |
