Engineering firm Bodycote revealed a pre-tax loss for the half year and warned, as yet, there is no sign of any meaningful improvement in demand levels.Loss before taxation came in at £53.1m for the half year to 31 December 20 from a profit of £38.2m previously. Revenue from continuing operations fell by 19.4% to £227.9m."Bodycote has been significantly impacted by the downturn in manufacturing activity in all parts of the world and the first half of 2009 saw further reductions in customer requirements," it said in Wednesday's company statement.It added, "Visibility continues to be limited due to the group's short order book and continuing uncertainty in market conditions. Whilst a number of market sectors now appear to be stabilising, there is, as yet, no sign of any meaningful improvement in demand levels."Bodycote said automotive and general industrial markets appear to have stabilised while aerospace and oil & gas sectors have softened.The interim dividend is unchanged at 2.95p per share.