Spear rods are made for smaller substrates which have a through going hole like indexable cutting inserts. Cutting inserts e. g. are lined up on the spear rod with spacers in between them in order to provide defined distance between them. All spear rods have a gear close to the bottom end.
The size of the gear should be equal or bigger than the outer circle of the substrates. The diameter of the spear rod should be smaller (about 0,3mm) than the diameter of the hole. Rods in length of 250 mm and 300 mm can be ordered directly here in the shop. Each other length can be delivered upon inquiry.
As default the teeth of the gear face counter clockwise (CCW) for base plates which also rotate CCW. The rods themselves in this case will rotate CW. If your planets rotate clockwise (CW) please mention that the teeth shall face CW.