Installation of the head belt
Turn the whole thing over to see the underside of the head.
Take the 75cm belt.
With the notches facing upwards, insert the belt into the upper hole.
Pick it up on the other side and make it come back to the right (beware of spins).
In the right-hand carriage, pass over the bearings and then return to the bottom (notches towards the bearing).
Pull it to get some slack.
Return the belt to the left carriage by passing under the head.
Pass the belt under the motor pulley and back over it.
Point the end of the belt towards the head. Place the belt in the slot (go to the last notch).
Take the other end and pull on it to tighten the belt. Tense without forcing, just so that everything stays in place. Push the belt to lock it into the notches on the head.