Tab Track Terminology

Bobbins or Runners These run along the track on small wheels and carry the drapes. Generally they are spaced at around 250- 300mm apart.

Rearfold Runners Runners with an attachment that grips the control line [until offstage] to enable a cloth to move off stage without gathering from the leading edge. Only normally used with painted cloths.

Master Runners The master runner is the lead runner. It will normally have a clamping plate to grip the control cord. For a centre opening track you will need two master runners. Clamp the handline to one runner, then thread it around the return pulley at the end of the track and clamp the returning part of the cord to the other master runner. Even if the drapes are just to be pulled along it is wise to have a master runner at the leading edges as this runner will take a greater strain than ordinary bobbins.

Overlap Arms Some master runners will take an overlap arm which allows centre opening drapes to overlap. The alternative is to overlap the tracks but to do this you will need overlap clips plus offset plates to ensure the hook clamps align with the flying bar.

Head Pulley This double sheave vertical pulley bolts to the operator end of the track. Sometimes two designs are available, one for overlap tracks and one for single tracks.

Return Pulley Horizontal pulley bolted to the far end of the track.

Floor Pulley These pulleys are fixed to the floor and the sheave can be adjusted to put tension in the cord. If your track needs to fly out then choose a foot stirrup pulley or a weighted pulley. If you choose a weighted pulley ensure that you use a polyester handline and that regular checks are made to guard against chafe.

Handline Tracks take 6 or 8mm diameter handlines. Nowadays most people choose matt black polyester line rather than jute sash. If you are using a weighted pulley do not use jute sash. For the track to operate the line needs to be tied [or clamped] to form a loop. The best place to do this is just behind a master carrier rope clamp as this position never has to pass through a pulley.