Hi Arron,
The wide belt is a 380mm wide belt that has an adjustable speed controlled conveyor belt that runs under the sanding belt. The work is fed under the sanding belt on the conveyor. In actual practice these machines are very difficult to set up and keep the sanding belt tracking evenly across the oscillating rollers. Also the supplied speed control unit is rather poor quality and I replaced that with a heavy duty industrial unit. ( I bought this machine instead of the usual large drum sanders where the sanding media is wrapped around a drum or drums.) These 380mm belts were I think around $40 each and as supplied fairly poor quality. I then found a local company who make better quality belts that I now use on all three of my sanding machines. The combination Hafco linisher/sander and Scheppach unit both use 150mm belts but the Scheppach belts are 2515mm long. I am planning to see if I can get some 180mm belts made to give better cover over the black slip cloth and stop it making the work. The key to all sanding is to take it easy and not try and remove too much in one pass. Since installing a Byrd helical cutter head on my thicknesser I have found with many timbers I require very little sanding where as the old straight cutter head gave a much poorer quality finish that needed a lot of sanding.
Cheers,
Paintman