Contents: SuperLube NLI 000 synthetic grease with Synclone, 1.5ml
The gears within your servo's transmission section have been machined to a finished tolerance measured in microns. These highly precise gear trains are greased during assembly with Superlube NMI 000 synthetic grease. For optimal service, it's what we recommend using during maintenance going forward.
Background:
As with any machine where sliding parts depend on lubrication to reduce friction, the metal will wear as they are burnished against each other. This process generates finely ground metallic particles composed of gear material. The term for this process is called break-in. And as a result of being burnished, the grease will darken as it holds the fine metal particles in suspension.
Note; this isn't an opinion, it happens due to physics and ignoring it won't make it go away. In fact, ignore it long enough and you risk discovery the now dirty grease (because it's loaded with metal particles), will become more and more abrasive. End result? It accelerate the wear between gears resulting in excess backlash beyond the called for design limits. Worse, the longer it's ignored (left dirty for particles to continue to accumulate) the more quickly wear occurs. Since replacement gear sets aren't free, then there's a stupid tax involved for being lax with maintenance - heads up!
In practice, 90% of the wearing-in process happens by about 5-hours. After this, the rate of wear decreases significantly as bed in and optimal operating clearances are attained. Recapping, the parts working against each other become smoother and thee excess metal is suspended in the grease become more, and more abrasive over time. It needs to be changed, just like changing the oil in your car.
Thus, it is recommended the gear train be disassembled, cleaned of old lubricant with solvent (gasoline works nicely, but do it outdoors with cross ventilation to protect your lungs and wear gloves against your skin absorbing bad chemicals).
Anyway, clean and re-lubricated the gear train at 5hrs, and then subsequently repeated at 25hr intervals for optimal life of your ProModeler servos. In the real world, for most modelers this conincides with season maintenance, or put another way, a good use for your time when it's too cold to enjoy your models!
Note; it's our opinion, as a matter of best practice, you should do this for all servos equipped with metal gears (regardless of brand, or model) unless you're so rich you don't care.