Embedded Files
I typically identify my tyres with 4 key dimensions, 18 x 9.5 x 2.6 x 5 is the dimensions for WASP - 01 size tyre shown left.
(A) tyre diameter when off the rim, in this case 18mm,
(B) tyre width, 9.5mm
(C) is the profile of the tyre or the height of the tyre wall, 2.6mm
(D) the width of the rib on the wheel the tyre is designed to fit, 5mm
There are more dimensions involved in the design and manufacture process but its confusing to list all of them as a tyre identifier.
Step 1 - Measuring the wheel
Step 1 - Measuring the wheel
Wheel measurements
Wheel measurements
Most of my tyres are made from 3D printed masters, this means I don't need to use the original rubber tyres from the car to make the molds. The advantage of this is that it allows me to produce as many cavities in the molds as i like and also ensures the finished tyres are perfectly concentric. The down side is that I need the exact sizes of the tyres to produce the 3D CAD model to print from.
The first thing to do when looking to design a new tyre is to take key measurements from the wheel and existing tyres (where available). Left are some of the measurements I take from the wheel, Rib width is critical and is used when Identifying a tyre Dimension (D)
Step 2 - Measuring the original tyre
Step 2 - Measuring the original tyre
Next the tyre is measured, the width of the tyre (B) is usually slightly larger than the width of the wheel, in this case 1.5mm wider, 0.75mm per side.
The profile (C) and the tyre diameter (A) help determine the minimum diameter of the wheel that the tyre is suitable for.
18mm (A) - 2 x 2.6mm (C) = 12.8mm. This tyre is suitable for wheels 8mm wide with a main diameter of 13mm or above.
As the inner diameter of the tyre is slightly smaller than the main diameter of the wheel the tyre will stretch when fitted and have a snug fit without needing to glue (in most cases).
Tyre measurements
Tyre measurements
Page updated
Google Sites
Report abuse