Many old dryers were modeled on the Hamilton principles of dryer design, even if they were not made by Hamilton. Most were termed "low airflow." There were some differences. The placement of the motor, fan and lights differ between the GE and the Hamilton. The lint screen is different, but in the same place. The door opening is larger on the GE and the belts are not the same size as the Hamilton's. WP, Norge, Westinghouse and others were not built like Hamiltons. I believe it was after 1956 when Consumer Reports noted that dryers had evolved from using higher temperatures and low airflow to using lower drying temperatures and higher airflow.
One of the reasons so many of the old dryers were quiet was the heavy-duty construction. Perforated inner drums meant that they had to have outer tubs. The outer tubs were heavily wrapped in Fiberglass insulation. They hold the heat so well that after the first load, successive loads dry in reduced time. Some, like the GE did not have a cool down period. The 1951 Hamilton has a 5 minute cool down period. Once the timer reaches that point, I start removing shirts & slacks, one at a time, and putting them on hangers. The weight and quality of the tub bearings are remarkable. The drums of many of these dryers, once the belts are removed, can be turned with one finger and will coast along, silently, with no sign of the drum being out of balance or out of round, for several revolutions. The motors were cast iron and had oil wicks for the front and rear bearings. If an older dryer of this type is noisy, it often can be hushed by replacing the belts. These old machines used hydraulic operating thermostats that are very responsive, sometimes cycling the heat off and then back on within a minute. On Hamilton parts lists, the heat control is labeled "oven thermostat." As with the first models of most anything, they were built far better than later models, almost over-built, due in part to the quality of the accepted standard of materials in use back then like heavier gauges of steel, reflecting the manufacturers' desire to present a product that would give long, trouble-free service under then unknown levels of use, so that the owners would be their best salespeople.
