Examples of single-needle machines where the thread groove  does not face left are Singer 17W15 308-stitch or Singer 69  bar tack. The thread groove most often faces the bobbin, but  not always in the case of a Horizontal Rotary Hook, such as  Singer 201-2. Read the manual, if the needle does not pick  up the bobbin thread, it may not be installed correctly. Take a cone of thread and place it on the thread stand. Route  the thread upward through the guide at the top of the stand and  then to the pre-tension thread guide on top of the arm of the  machine.  [Figure 6-80]  Most modern machines use a similar  method of threading. However, there may be additional  thread guides of different shapes to route the thread through.  This is why the rigger should have a copy of the operator’s  manual for proper threading of each machine. Once the machine is threaded correctly, take a sample of  material suitable for the type of machine, thread, and needle.  Form several layers and place it under the presser foot. Lower  the presser foot while holding the upper and lower threads  securely to the rear of the presser foot. Turn the balance wheel  again and run a few stitches by hand to see if the machine  sews properly. If everything works as expected, turn the  power on and begin sewing. If you are unfamiliar with this  particular machine, begin slowly until you get the feel of the  clutch and speed of the machine. The harder you push, the  faster the machine runs. Some industrial machines are able to  run very fast. This can intimidate many. If you need to slow  the machine down, you can replace the pulley on the motor  with one smaller pulley. A parts and repair shop will have  or be able to order the pulley you need. Order the smallest  Figure 6-79.  Needle with left orientation. Figure 6-80.  Thread the machine. 6-22