Tennis indoor clay court milling and grinding


Usually indoor clay court could be very humid or wet if it was already too wet when it was covered after summer time. Conversely, it could happen that a clay playground that is too dry once the structure has been assembled would maintain a state of excessive dehydration of the clay surface so it would be better to water it before using Venus, especially to prevent that a too dry milled clay will create a bothersome dirty dust against the operator and the environment.

However, the conditions of an indoor red clay tennis court often lead to a state of anomalous humidity and compactness, which combined with the fact that red clay is missing becouse of the trampling of the players, we often find a surface situation with little clay layer, wet...ultra compact and very hard!

The following procedures are always to be used subject to a subjective case-by-case assessment of the condition of each red clay playground.

Estimated time: 3,5/4 hours

Time to restart playing: 24 hours after maintenance

Playground conditions: hard (but not cemented surface as from outside where warm sun makes the crust also harder), damp and compact tennis red clay with possible points of scarce quantity of top layer. In the opposite case that the playground has been covered and still carried an excess of humidity, the clay court could have a pasty surface to be grinded in several steps, considering whether to carry out maintenance in several moments while waiting for it to dry.

White stripes: they should not be removed unless the situation has degenerated to the point that the lines are very disconnected and totally devoid of flatness (in this case refer to the precautions on the page: EXTRAORDINARY MAINTENANCE

Direction line indicator: to run along the white lines without crossing with the venus blades action

Preliminary measures:

- make 3/4 cm deep core holes in 8 random positions in the whole playground to verify that there are no stones that have emerged from the crushed gravel second and third layers and that there are no surfacing substrates and drain stones that have emerged from the botom of the clay court construction

- clean the white lines to see them clearly and run along the stripes with rod indicator mounted on the right side of Venus chassis (if you cross the white lines lift the blades action to not damage them!)

- if the lines are disconnected, compact them with a roller

Pass the venus a first pass in the longitudinal direction, milling a maximum of 8/10 mm of red clay top layer, and if the surface is still hard and the clay is sufficiently abundant in each point, mill with Venus at the intersection in the other direction, forming a grid of milling lines.

Final operations:

Once you milled top layer clay has use a straightedge to balance any non-homogeneous quantities on the whole playground, and after 4 hours for the surface to rest and dry, it is possible to add a small quantity of new top layer of red clay (very thin quantity). The subsequent passage of the net to break the largest grains of clay will allow to have an ideal surface but which will need at least 12 hours of resting for an autonomous recompaction. The morning after, before stating to play tennis it could be helpfull to use a no gear roller compactor to complete the resurfacing process.


In indoor fields it is not recommended to add too much water by wetting the clay for maintenance as it is common use in outdoor refurbishing. Mind that the regenerating effect of Venus blades gives volume to the old compacted surface naturally distributing the water present in the underside.

Operator at work with Venus during a restoration on very compact and hard indoor red clay tennis surface: one man breaks into clods the hardest top layer and the second finely tills the clay working with a second passage of Venus grinding equipment