MHW-3BOMBER R3 Manual Coffee Grinder Instruction Manual

1. Product Overview

The MHW-3BOMBER R3 Manual Coffee Grinder is designed for precision coffee grinding, featuring a CNC stainless steel conical burr and an external adjustment mechanism. It is suitable for various brewing methods, including espresso, French press, drip coffee, and more. The grinder includes a magnetic powder bin and a set of five grind sieves for enhanced control over your coffee grounds.

Image 1.1: MHW-3BOMBER R3 Manual Coffee Grinder and included accessories (handle, burr, sieves, cleaning brush, magnetic bin).

2. Setup

2.1 Unpacking and Initial Inspection

• Carefully remove all components from the packaging.
• Verify that all parts are present: grinder body, handle, magnetic powder bin, 5 grind sieves, and cleaning brush.
• Inspect the grinder for any visible damage. If damage is found, contact customer support.

2.2 Initial Cleaning

• Before first use, disassemble the grinder (refer to Section 4.1 for disassembly).
• Use the included cleaning brush to remove any manufacturing dust or debris from the burr and internal components.
• Wipe the exterior of the grinder with a clean, damp cloth. Do not immerse the grinder in water.
• Ensure all parts are completely dry before reassembly.

3. Operating Instructions

3.1 Adjusting Grind Size

The MHW-3BOMBER R3 features an external grind adjustment mechanism with 60 clicks per full rotation, offering a maximum of 180 clicks for precise control. To adjust the grind size:

1. Hold the grinder body firmly.
2. Rotate the adjustment ring located near the top of the grinder.
3. Turning the ring clockwise results in a finer grind.
4. Turning the ring counter-clockwise results in a coarser grind.
5. Refer to the markings on the adjustment ring for reference. Each click represents approximately 0.016mm change in grind size.

Image 3.1: Adjusting the external grind setting by rotating the ring.

3.2 Recommended Grind Settings

The following table provides general recommendations for grind settings based on common brewing methods. These are starting points and may require fine-tuning based on your specific beans and preferences.

Image 3.2: Recommended grind settings for different coffee brewing methods.

Note: After resetting the grind setting, do not forcefully rotate the grinding core to avoid damage.

3.3 Grinding Process

1. Load Beans: Open the top lid and pour 15-20g of whole coffee beans into the hopper.


Image 3.3: Pouring coffee beans into the grinder.

2. Attach Handle: Securely attach the handle to the top shaft.
3. Grind: Hold the grinder body firmly and rotate the handle clockwise to begin grinding. Apply steady, even pressure.

Image 3.4: Grinding coffee beans with the manual grinder.
4. Collect Grounds: Once grinding is complete, detach the magnetic powder bin from the bottom of the grinder.

3.4 Using the Magnetic Powder Bin

The grinder features a magnetic powder bin for easy attachment and removal. It has a capacity of 20g. The 72 powerful magnets ensure a secure connection and prevent spills. To remove, simply pull the bin downwards. To reattach, align it with the base and the magnets will secure it.

Image 3.5: The magnetic powder bin with 72 magnets for secure attachment.

3.5 Utilizing Grind Sieves

The MHW-3BOMBER R3 includes 5 finely calibrated sieves (300um, 400um, 500um, 600um, and 850um) to help remove fine powder (fines) from your grounds, which can improve the clarity and sweetness of your brew. For espresso, it is generally recommended to omit the sieve.

1. After grinding, place the desired sieve on top of a clean container.
2. Pour the ground coffee onto the sieve.
3. Gently shake the sieve from side to side for approximately 15 seconds to separate the fine powder.
4. The remaining grounds on the sieve are ready for brewing.

Image 3.6: Step-by-step guide for using the grinder and sieves.

Image 3.7: The five grind sieves and their impact on fine powder reduction.

4. Maintenance

4.1 Disassembly for Cleaning

Regular cleaning ensures optimal performance and longevity of your grinder.

1. Remove the handle.
2. Unscrew the adjustment ring completely until the top burr assembly can be removed.
3. Carefully remove the inner burr and central shaft assembly.
4. Separate the outer burr from the grinder body if necessary (it may be fixed).

4.2 Cleaning the Components

• Use the provided cleaning brush to thoroughly brush off any coffee grounds from the conical burrs (inner and outer), central shaft, and inside the grinder body.


Image 4.1: The included cleaning brush.

• Clean the magnetic powder bin and sieves with warm, soapy water. Rinse thoroughly and allow them to air dry completely.
• Do not use water or abrasive cleaners on the burrs or the main grinder body, as this can cause rust or damage.

4.3 Reassembly

Reassemble the grinder by reversing the disassembly steps. Ensure all parts are correctly aligned and tightened before use.

4.4 Storage

Store the grinder in a clean, dry place away from direct sunlight and moisture when not in use.

5. Troubleshooting

• Grinder feels stiff or difficult to turn: Check for foreign objects (e.g., small stones) among the coffee beans. Ensure the grind setting is not set too fine, which can increase resistance.
• Inconsistent grind size: Ensure the burrs are clean and free of old coffee residue. Verify that the central shaft is stable and not wobbling.
• Coffee grounds sticking to the bin: This can be due to static electricity. A small drop of water (RDT method) on the beans before grinding can help reduce static.
• Magnetic bin not attaching securely: Check for any debris on the magnets of the bin or the grinder body. Ensure the bin is aligned correctly.

If you encounter issues not listed here or require further assistance, please contact customer support.

6. Specifications

Image 6.1: Product dimensions and component sizes.

• Brand: MHW-3BOMBER
• Model Number: G5847B
• Color: Black
• Material: SUS304, SUS420, Aluminum alloy, silicone, walnut, magnet
• Burr Type: CNC Stainless Steel Conical Burr (Rapidity-3 Grinding Burr)
• Grind Adjustment: External, 60 clicks per rotation (max 180 clicks)
• Grind Sieves: 5 sizes (300um, 400um, 500um, 600um, 850um)
• Powder Bin Capacity: 20g (approx.)
• Item Weight: 1.6 Pounds (approx. 725g)
• Product Dimensions: 7.87"L x 1.97"W x 7.48"H (200mm L x 50mm W x 190mm H)

7. Warranty and Support

7.1 Warranty Information

This product is covered by a manufacturer's warranty against defects in materials and workmanship. Specific warranty terms and duration may vary by region and retailer. Please retain your proof of purchase for warranty claims.

7.2 Customer Support

For technical assistance, troubleshooting, or warranty inquiries, please contact MHW-3BOMBER customer support through the retailer where the product was purchased or visit the official MHW-3BOMBER website for contact information.