Gas Strut Newton Rating for Cabinets: How to Calculate

Choosing the right gas strut Newton rating for your cabinet is crucial for ensuring smooth, controlled opening and closing. Too weak, and the door won’t stay open. Too strong, and it might slam shut or be difficult to close. This article will guide you through calculating the ideal Newton force for your cabinet gas struts.

Why is the Newton Rating Important for Cabinet Gas Struts?

The Newton rating (N) is the unit of force used to measure the power of a gas strut. Selecting the correct Newton rating ensures your cabinet door or lid opens smoothly, stays open at the desired angle, and closes without slamming. Correct force also extends the lifespan of the strut and prevents damage to the cabinet.

Using an incorrect Newton rating can lead to several problems, including:

Door Slamming: A strut with too much force can cause the door to slam shut, potentially damaging the cabinet or causing injury.
Difficulty Closing: If the strut is too strong, it can be difficult to close the cabinet door, requiring excessive force.
Door Won’t Stay Open: A strut with too little force will not be able to hold the door open, causing it to fall closed.
Premature Wear: Using the wrong force rating can put undue stress on the strut, leading to premature wear and failure.

Before we deep dive into the factors that can affect Newton rating, it can be useful to get familiar with our Gas Spring Force Calculator

How Do I Know What Newton Rating Gas Strut To Use For My Cabinet?

To determine the correct Newton rating for your cabinet gas struts, you need to consider several factors, including the weight of the door, its dimensions, the mounting position of the strut, and the desired opening angle. Here’s a step-by-step guide:

Step 1: Gather Your Measurements

Before calculating the Newton rating, you will need the following measurements:

Door Weight (W): Weigh the cabinet door using a scale. Ensure you are only measuring the door’s weight, not the entire cabinet. Convert the weight to kilograms (kg).
Distance from Hinge to Centre of Gravity (L1): Measure the distance from the hinge to the centre of gravity of the door. The centre of gravity is the point where the door would balance perfectly if supported. For a rectangular door, this is typically halfway across the width and height. Measure this distance in millimetres (mm).
Distance from Hinge to Strut Mounting Point on Door (L2): Determine where the gas strut will be mounted on the door. Measure the distance from the hinge to this mounting point in millimetres (mm).
Angle of Door When Open (θ): Measure the desired opening angle of the door in degrees. This is the angle between the closed and fully open position.

Step 2: Calculate the Torque

Torque is the rotational force acting on the door. It is calculated using the following formula:

Torque (τ) = W * L1 * g * cos(θ)

Where:

W = Weight of the door in kilograms (kg)
L1 = Distance from hinge to centre of gravity in metres (m)
g = Acceleration due to gravity (approximately 9.81 m/s²)
θ = Angle of the door when open in degrees
cos(θ) = Cosine of the angle θ

Example:

W = 5 kg
L1 = 0.3 m (300 mm)
g = 9.81 m/s²
θ = 75 degrees

τ = 5 kg * 0.3 m * 9.81 m/s² * cos(75°)

τ = 5 * 0.3 * 9.81 * 0.2588

τ ≈ 3.79 Nm

Step 3: Calculate the Required Force

To calculate the required force (F) for the gas strut, use the following formula:

F = τ / L2

Where:

τ = Torque in Newton-metres (Nm)
L2 = Distance from hinge to strut mounting point on the door in metres (m)

Using the previous example, let’s assume L2 = 0.2 m (200 mm)

F = 3.79 Nm / 0.2 m

F ≈ 18.95 N

Step 4: Account for Safety Factor

It’s always a good idea to add a safety factor to your calculation to account for variations in manufacturing tolerances, wear and tear, and other unforeseen factors. A safety factor of 10-20% is generally recommended. This means multiplying the calculated force by 1.1 to 1.2.

Using a safety factor of 10%:

Adjusted Force = 18.95 N * 1.1

Adjusted Force ≈ 20.85 N

Therefore, in this example, you would need a gas strut with a Newton rating of approximately 21 N.

What Factors Affect the Gas Strut Newton Rating?

Several factors can influence the required Newton rating for your cabinet gas struts:

Door Weight: Heavier doors require higher Newton ratings.
Door Size: Larger doors create more leverage, requiring higher Newton ratings.
Mounting Position: The closer the strut mounting point is to the hinge, the higher the Newton rating required.
Opening Angle: Larger opening angles may require higher Newton ratings to hold the door open.
Friction: Friction in the hinges or door mechanism can affect the required force.

Gas Strut Placement Considerations

Correct placement of the gas strut is as important as the Newton rating. Here are some considerations:

Parallel Alignment: Ensure the strut is aligned parallel to the door when closed to avoid binding or excessive wear.
Solid Mounting Points: Mount the strut to solid, reinforced areas of the cabinet and door to prevent damage.
Clearance: Ensure there is adequate clearance for the strut to move freely throughout the full range of motion.
Symmetrical Placement: If using two struts, place them symmetrically on either side of the door for balanced support.

Practical Tips for Choosing the Right Strut

Here are some practical tips to help you choose the right gas strut for your cabinet:

Start with an Estimate: If you are unsure, start with a strut that has a slightly lower Newton rating than calculated. It’s easier to upgrade to a stronger strut than to deal with a door that slams shut.
Test and Adjust: After installing the strut, test the door’s operation. If it doesn’t stay open or closes too easily, adjust the mounting position or swap the strut for one with a different Newton rating.
Consider Adjustable Struts: Some gas struts allow you to adjust the force. These can be useful if you are unsure about the exact Newton rating needed.
Consult a Professional: If you are unsure, consult a professional cabinet maker or hardware specialist for assistance.

Where to Buy Gas Struts for Cabinets in the UK

You can find gas struts for cabinets at various retailers in the UK, including:

Online Retailers: Amazon, eBay, and other online marketplaces offer a wide selection of gas struts. Be sure to check customer reviews and product specifications before purchasing. Check prices on Amazon »
Hardware Stores: B&Q, Wickes, and other hardware stores carry a range of gas struts for various applications.
Specialty Suppliers: Some suppliers specialize in gas struts and related hardware. These suppliers can offer expert advice and a wider selection of products.

Gas Strut Brands Compared: Stabilus, Bansbach

When selecting gas struts, consider reputable brands known for quality and reliability. Some popular brands include:

Stabilus: A leading manufacturer of gas struts, known for their high-quality products and wide range of applications. Stabilus official website
Bansbach: Another reputable brand offering a variety of gas struts and dampers for industrial and commercial use. Bansbach official website
Sachs: A popular German brand.

These brands offer different features and price points, so compare products carefully to find the best option for your needs.

DIY Cabinet Gas Strut Installation Guide

Installing gas struts on your cabinet is a straightforward process. Here is a general step-by-step guide:

Gather Tools and Materials:
- Gas strut
- Mounting brackets
- Screws
- Drill
- Screwdriver
- Measuring tape
- Pencil
Mark Mounting Points: Measure and mark the mounting points on the cabinet and door. Ensure the strut will be parallel to the door when closed.
Install Mounting Brackets: Attach the mounting brackets to the cabinet and door using screws. Ensure the brackets are securely fastened.
Attach Gas Strut: Snap the gas strut onto the mounting brackets. Ensure it clicks into place securely.
Test Operation: Open and close the door to test the strut’s operation. Adjust the mounting position if necessary.
Fine-Tune: Make any necessary adjustments to ensure smooth, controlled movement.

Gas Strut Too Strong / Too Weak

Having a gas strut that is too strong or too weak is a common problem; it might cause the cabinet door to slam shut or not stay open. If your gas strut is too strong, consider replacing it with one that has a lower Newton rating or adjusting the mounting position to reduce the leverage. If it’s too weak, opt for a strut with a higher Newton rating or relocate the mounting points to increase leverage.

Conclusion

Selecting the correct gas strut Newton rating for your cabinets is vital for ensuring smooth and safe operation. By following the steps outlined in this guide, you can calculate the ideal force for your specific application. Remember to consider factors such as door weight, mounting position, and desired opening angle. With the right gas strut, your cabinet doors will operate flawlessly for years to come.

For bespoke or bulk orders, contact our industrial team.

Gas Strut Newton Rating for Cabinets: How to Calculate