  In this paper we extend the estimate of the value of the lattice spacing a in
units of the r0 scale at values of the bare coupling larger than those
available. By using results from the computation of the renormalised coupling
in the Schroedinger functional formalism we find that from beta \simeq 7 onward
the behaviour predicted by asymptotic freedom at tree loop describes very well
the data if a value of (r0 Lambda) slightly lower then the latest available is
used. We also show that, by sticking to the current value, an effective four
loop term can describe as well the data. The systematic relative error on the
lattice spacing induced by the choice of the procedure is between 1% and 3% for
6.92 < beta < 8.5.
