We need to drill a three-quarter inch hole, which can be a fairly violent operation with a hand-drill... plus of course we are adapting as we go along and therefore none of it is being done in sequence. In the fulness of time anyway this will be plastic or carbon fibre sheet that can be laser-cut anyhow. In the interim however I've clamped timber off-cuts either side, which takes the sting out of these super-sized drill-bits.
