The present invention relates to a process for producing aliphatic and aromatic C2-C6 hydrocarbons by submitting a reformed gas to Fischer-Tropsch synthesis. A bib contains a central pocket for insertion of a soft pillow, and a baby bottle holder attachment portion. The negative and positive torque limits are reduced independently as a temperature of the machine increases. The lateral position of the moving tape is sensed and the rotating roller barrel is tilted in response to the sensed lateral position of the moving tape to control the lateral position of the moving tape.