Grabo’s technology and technical spec
Grabo incorporates multiple patents and technological innovations developed by engineers at Nemo Power Tools over the course of several years. This page summarizes some of the product’s unique technical capabilities.
1. Adhesion to rough surfaces
Traditional suction cups are only capable of creating a good seal with flat, clean and airtight surfaces such as glass. However, Grabo’s unique seal allows the tool to adhere to rough, etched surfaces.
The maximum surface roughness which Grabo can attach to depends on the exact ‘profile roughness parameters’ (The geometry of peaks and valleys in the material), and is generally limited to an amplitude of about 2.5mm (0.1 inch). This capability allows Grabo to create a seal with the majority of patterned tiles, pavers and construction materials.
2. Keeping a seal against porous materials
A porous surface is any surface which allows gas to flow though it. Many construction materials are porous to varying degrees. Most common porous construction materials are: wood, concrete, rock, gypsum boards and many ceramics and tiles.
Standard “suction cups” can not hold porous materials for more than a few seconds, even if the surface is flat enough to create a seal. A vacuum cavity on top of a porous material will quickly fail as air seeps in through the material.
Grabo overcomes this and allows secure adhesion to these materials by constantly pumping out a large volume of air at a rate greater than the diffusion rate of air though the surface.
The physics behind the calculation of flow rates through different materials is both complex and interesting. The flow rate required from Grabo to keep a strong vacuum seal against a porous surface, is generally described by a formula of generalized Murray’s law:
The flow rate is than multiplied by the surface area under the seal for a given pressure differential, which results in the flow rate and power requirement from Grabo’s internal electric pump.
However, as interesting as the engineering is, users of Grabo do not need to worry about the science. All you need to know, is the Grabo is designed to work well on some of the most common porous materials in the industry.
* For specific max lifting force capabilities, refer to the table ‘Lifting force under different conditions’ table in the bottom of this page.
Your Grabo includes the following main components:
Connecting Straps to the Grabo
- Locate the four holes around the handle of the Grabo. You can connect the strap to any two or four of these holes using the provided hooks or any carabiner hook rated to a minimum of 180kg (400lbs).
- Secure each of the clips at the ends of the strap into a hole.
Charging the Battery
- Connect the mains plug of the battery charger to an electrical outlet.
- Connect the charger to the battery.
The battery begins charging as soon as it is connected to the charger, and stops charging as soon as it is full. A red light on the charger indicates that the battery is being charged. Once the battery is fully charged, the charger LED will change to green.
Replacing the Rubber Foam Seal
- Grabo’s double foam seal is a patented soft sealing system, designed for sealing rough un-even surfaces as well as providing high friction and strong adhesion to many different materials. The seals are consumable rated to last 3,000 cycles under normal use, and can easily be replaced if they wear-out. Check your seals regularly and replace them if any damage is visible.
- Remove the rubber foam seal that has become worn or damaged by pulling it out of it’s niche. Use a flat screwdriver or knife to carefully pull the seal out from its plastic base. Pulling on the black foam directly will likely cause it to tear.
- Gently press the new rubber foam seal in to position, ensuring that it fits snuggly and securely.
|Battery Voltage||16V Li-ion|
|Battery Cell Specification||2.2 Ah|
|Dimensions||297 x 181 x 115mm
(11.7 x 7.1 x 4.5 inches)
|Net weight (with battery)||1.5kg (3.3lbs)|
|Working temperature||0°C – 60°C (32°F – 140°F)|
|Working time (full charge)||1.5 hours|
Lifting force under different conditions
Max Lifting Force
This table provides a rough estimation of the max perpendicular adhesion force and max parallel adhesion force on different materials. These values may vary depending on material and surface conditions.
|Perpendicular Hold||Parallel Hold||P/P Ratio|
|Glass||170kg (375lbs)||120kg (265lbs)||0.7|
|Metal||110kg (242lbs||110kg (242lbs)||1|
|Plastic||100kg (220lbs)||100kg (220lbs)||1|
|Wood||100kg (220lbs)||65kg (143lbs)||0.65|
|Ceramic Tile||170kg (375lbs)||120kg (265lbs)||0.7|
|Rough Concrete||80kg (176lbs)||80kg (176lbs)||1|
|Plasterboard||75kg (165lbs)||65kg (143lbs)||0.87|
|Rough Slate||80kg (176lbs)||80kg (176lbs)||1|
For a more accurate estimation, check the pressure gauge on your Grabo and use the table below to convert pressure values to max lifting force values. (Parallel holding force values can be calculated using the P/P ratio provided above for different materials.)
|Pressure (bar)||Max perpendicular holding force|
|-0.8||170 kgf/ 374 lbsf|
|-0.6||128 kgf / 281 lbsf|
|-0.4||85 kgf / 187 lbsf|
|-0.2||43 kgf / 94 lbsf|
|-0.1||21 kgf / 47 lbsf|