during the war gläser switched to war production, making wings and landing gear for fokker fighter planes. after 1918 the focus returned to car bodies and horse-drawn carriages. simultaneous production of both car bodies and horse carriages was not a problem, since at this stage both employed the same meticulous timber frame technology, with the gaps in the frame filled by hand-made sheet panels or by fabric, applying the weymann patented methods. it was not till the 1930s that timber frame bodies began to be superseded by "all-steel" car bodies, manufactured using large expensive presses (or labour-intensive hand-beaten steel panels), applying, in particular, the patent technology from ambi budd who built their own large-scale car body factory in berlin, transforming the economics of automobile production by the end of the 1930s. this increasingly restricted bespoke car body builders to the upper end of the price scale, but that was already the sector where gläser-karosserie were at their strongest, providing bespoke bodies for customers who had purchased their cars in bare chassis form from any one of a wide range of auto makers including (but not restricted to) adler, bmw, hanomag, horch, mercedes benz, opel, steyr and wanderer. body types included the phaeton, coupé, landaulet, limousine, pullman and (still a particular gläser speciality) cabriolet.