## 2 Comments

1. Jeff says:

Krunal,

Hi, I am looking to set-up a calculating spreadsheet where I can input a persons weight and determine the minimum thickness requirements when using MDF for a Rocking Chair.

I have been using 16mm MDF for smaller chairs for the kids but now have a client of 145kg and need to ensure it is strong enough for his use.

1. To set up a calculating spreadsheet to determine the minimum thickness requirements for MDF when designing a rocking chair, you can follow these steps:

1. Determine the Weight Capacity: Start by determining the weight capacity or maximum load that the rocking chair needs to support. In your case, you mentioned a client weight of 145kg.
2. Gather Material Information: Collect information about the material properties of MDF. This includes the modulus of elasticity (E) and the allowable stress (σ) for MDF.
3. Choose a Design Factor: Determine a suitable design factor to account for safety and potential variations in material properties or loading conditions. A common design factor for furniture design is typically between 1.5 to 2.
• Calculate the Required Minimum Thickness: The minimum thickness of the MDF can be calculated using the formula:
• Minimum Thickness = (Weight Capacity * Safety Factor) / (E * σ)
• Substitute the weight capacity, safety factor, modulus of elasticity, and allowable stress values into the formula to calculate the minimum thickness.
4. Set up the Spreadsheet: Create a spreadsheet with the necessary columns for input and calculations. Include columns for weight capacity, safety factor, modulus of elasticity, allowable stress, and minimum thickness. You can also add additional columns for any other relevant information or calculations you may need.
5. Input Data and Calculate: Input the weight capacity, safety factor, modulus of elasticity, and allowable stress values into the appropriate cells in the spreadsheet. Then, use the formula mentioned in step 4 to calculate the minimum thickness in the corresponding cell.

By using this spreadsheet, you can input different weight capacities or adjust the design factors to quickly determine the required minimum thickness for MDF in a rocking chair design.

Please note that the calculated minimum thickness is a starting point, and it is always recommended to consult with a qualified structural engineer or furniture designer to ensure the safety and structural integrity of the rocking chair design, especially for larger weight capacities.

Additionally, keep in mind that MDF is not typically recommended for load-bearing or structural elements in furniture design, as it has limitations in terms of its strength and durability. It may be advisable to consider alternative materials, such as solid wood or plywood, for critical load-bearing parts of the rocking chair.

If you have any further questions or need assistance with any specific calculations or spreadsheet setup, feel free to ask.