Quick answer
A slipping follow focus usually comes down to gear mesh, rod clamp tension, or a worn drive gear. Check those three points first before ordering parts.
Why gear mesh matters most
The gear drive in your follow focus must engage the lens gear with just enough pressure. Too loose and the teeth skip under load; too tight and the gear binds or wears prematurely. Most consumer follow focuses use a simple spring-loaded arm or adjustable height gear drive. The Sevenoak SKFX1, for example, uses an adjustable height gear drive precisely so you can dial in that mesh depth.
Diagnosis: symptom, cause, fix, stop point
- Symptom: The focus wheel turns but the lens gear does not move, or it moves unevenly.
- Likely cause: Gear mesh too shallow. The drive gear is not engaging enough teeth on the lens gear.
- Corrective action: Loosen the gearbox mounting screws, slide the gear drive closer to the lens gear, then retighten. On the Sevenoak SKFX1, use the adjustable height gear drive to raise or lower the gear until full tooth contact is achieved. If the gear still slips after full mesh adjustment, inspect the gear teeth for wear or debris.
- Stop or replace point: If the drive gear teeth are visibly rounded or chipped, or if the rod clamp cannot hold the follow focus steady even after tightening, replace the gear or the unit. A slipping follow focus with worn teeth will damage the lens gear over time.
Product facts
-
Sevenoak Follow Focus: The Sevenoak SKFX1 is a professional follow focus lens device manufactured in anodised aluminium with a magnetic marking disc and adjustable height gear drive. The adjustable gear drive lets you fine-tune gear depth without swapping parts, which directly addresses the most common slipping cause.
Sevenoak Follow Focus
