ROK Coffee Grinder

The ROK Coffee Grinder is a manual burr grinder.

ROK Coffee Grinder
Manufacturer: ROK
Model Name: Coffee Grinder
Type: Grinder

Machine Description

Made possible by a dedicated community of crowd funders from Indiegogo, the ROK Coffee Grinder is a revolutionary manual grinder for all forms of coffee preparation. The grinder boasts durable die cast aluminum construction with engineering grade components for ergonomic operation and long lasting performance. Your coffee is ground by a set of 48mm hardened steel burrs with a double bearing drive shaft and a Acetal plastic gears. The gears that power the ROK Coffee Grinder are made from Acetal, an engineering plastic that possesses qualities of both plastic and metal. With high tensile strength, low friction, light weight, and durability, it was the perfect choice to be paired with a reliable, long lasting set of burrs. There is also a non-slip ring located underneath the base, which guarantees stability while grinding on any flat surface. Secure it to your counter or tabletop for a semi-permanent fixture in your kitchen.

Unlike most manual grinders, beans are evenly ground with minimal effort. The non-slip ring located below the base ensures complete stability while the grinder takes only 62 revolutions (approximately 30 seconds) to prepare a double shot of espresso. With the ROK Coffee Grinder it's your choice whether you prefer stepped or stepless grinding. A pair of washers can be installed or removed from the double bearing drive shaft to transition the grinder from stepped or stepless grinding. Stepless grinders have an infinite number of grind settings allowing you to dial in your exact fineness for the perfect extraction parameters. Each ROK Coffee Grinder also ships with a metal cup/tamper that can be used to measure whole beans, catch ground coffee, and tamp the portafilter of the ROK Espresso Maker.

Basic Usage

Unboxing The ROK Grinder

The manufacturer has provided the unboxing video below to demonstrate unboxing the grinder and the essential components that come with the machine.

Getting Started

The manufacturer has provided basic usage instructions for the ROK Coffee Grinder.

Grinder Burr Key Upgrade

An earlier version of the ROK Coffee Grinder used a different burr key, so new burr keys were supplied when these machines shipped out. Machine which were manufactured later come with this burr key already installed. The video below shows how to install the new burr key.

Cleaning & Maintenance

Maintenance on the ROK Coffee Grinder is simple. Regularly take the grinder apart and brush down the burrs with a grinder brush or an old toothbrush, and wipe down the shaft to remove any built-up coffee residues.

Troubleshooting

Staticky Coffee

The manufacturer has provided the informational video below showing how to dissipate static when grinding. Please note that if the machine is set to a turkish style grind clumping and clinging may be unavoidable.

Burr Sticking After Adjustment

The easiest way to check if the adjustment wheel is working is to unwind and then wind it while looking down into the burrs. You should see a gap open and close.If the burr seems stuck when unwinding the adjustment wheel, try jiggling the main turn-handle whist beans are in the hopper. This normally frees it. Oily, caramelized, or flavored beans may leave behind sticky residues or cause coffee grinds to clump around these parts; this may be a sign to take the burr assembly apart and remove the coffee buildup.

If the Burr is not easily loosened, then the Burr may have been over-tightened onto the machine. It is important not to tighten down the adjustment wheel too much. This will cause the burrs to rub against each other, and can cause the inner burr to become stuck on the shaft.

Grinder Arm Falling Off

The arm of the grind is only meant to turn in the clockwise direction. If the arm is turned counter-clockwise it will unthread itself and fall off. If you are left handed simply turning the grinder around will not work, and will cause the grinder arm to unthread itself. Refer the instruction manual for instructions on how to flip the grinding mechanism around for left handed use.

Adjustment Wheel Hole Off Center

The hole of the adjustment wheel may look off center in some cases, but it is the paint that is off center, not the hole itself. After testing several adjustment wheels the threaded hole is always perfectly centered, although the hole in the paint may be slightly off center in some cases. This does not affect functionality at all, and is simply a result of the method used to apply the paint to the wheels.

Burr Not Centered/Inconsistent Grind

If the inner burr looks like it is not centered properly, or the grind is coming out inconsistently, then the burr assembly may need to be realigned.

1. First check to make sure the new burr key is installed on the machine. The new burr key helps keep the inner burr more tightly centered on the shaft.
2. It's actually the outer burr which is not centered properly. This can give the illusion of the inner burr being off center.
   1. Loosen the 2 Allen headed grub screws on front and back of the metal hopper using the included allen key; the screws do not need to be fully removed.
   2. Hand tighten the adjustment wheel until the burrs are sitting flush; you will be able to see when they're flush by looking at the bottom of the burr plates by looking below the grinding chamber. The adjustment wheel will also start to give considerable resistance; do not over-tighten.
   3. Tighten the two grub screws back into place, taking care not to over-tighten.
   4. If the burrs still do not look centered try removing the outer burr completely and then reassembling. The outer burr can shift from side to side slightly, so it needs to be centered with the inner burr.

Manuals & Diagrams

ROK Espresso Maker
Machine Manual:	Not Available
Parts Diagram:
Parts Diagram Cross Reference:

Specifications

Basic Specs
Width:	6.81 in.
Height:	11.02 in.
Depth:	8.27 in.
Weight:	6 lbs
Housing
Clearance Height For Portafilter:	2.25 in.
Built-In Tamper:	No
Housing Materials:	Aluminum
Bean Hopper Material:	Aluminum
Removable Hopper:	No
Frame:	Aluminum
Usage
Grind Selection:	All Grinds
Recommended Applications:	Home
Components
Grinding Method:	Burr
Burr Type:	Conical
Burr Material:	Stainless Steel
Burr Size:	48 mm.
Dispensing
Dosing Options:	Doserless
Portafilter Compatibility:	All
Controls
Number Of Grind Settings:	Infinite
Type Of Controls:	Manual Adjustment Wheel
Step Type:	Stepped/Stepless
Details
Country Of Manufacture:	China
NSF Certified:	No