Evaluation of 3D-printed pin materials on the deflection of medium-density fiberboard and particleboard shelves

Seker, S. (2026). "Evaluation of 3D-printed pin materials on the deflection of medium-density fiberboard and particleboard shelves," BioResources 21(2), 3231–3247.

Abstract

The deflection behavior and safety performance were studied for medium-density fiberboard (MDF) and particleboard (PB) shelves reinforced with metal, polylactic acid (PLA), and polyethylene terephthalate glycol (PETG) pins. Experimental testing and finite element analysis (FEA) were used to assess the effects of shelf material, pin material, and filament color on the global mid-span deflection of the shelf, load capacity, and safety factors. Results indicated that MDF shelves exhibited lower deflection and higher load-bearing capacity than PB shelves, highlighting the importance of material density and homogeneity. Metal dowels provided the lowest deformation and highest safety factors for both shelf types, followed by PLA and PETG pins. Variations in filament color and pigment caused only minor differences in PLA pins, while finite element simulations closely matched the experimental results, confirming the reliability of computer-aided analysis for predicting deflection behavior and preventing material damage. Experiments conducted in accordance with BS EN 16122 (2012) and TS EN 9215 (2005) demonstrated that material and filament characteristics significantly affected deflection (R² = 96.1%, adjusted R² = 94.2%), and that MDF panels reinforced with high-strength, preferably metal, pins provide safe and durable shelf systems with a minimum safety factor of ≥ 2 to 3.

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Evaluation of 3D-Printed Pin Materials on the Deflection of Medium-density Fiberboard and Particleboard Shelves

Sedanur Seker *

DOI: 10.15376/biores.21.2.3231-3247

Keywords: Shelf deflection; PETG; PLA; Safety factor; FEM; Coloured filament

Contact information: Forest Industry Engineering Department, Faculty of Forestry, Forest Industry Machinery and Management, Istanbul University-Cerrahpaşa, İstanbul 34473, Türkiye;

* Corresponding author: sedanur.seker@iuc.edu.tr

Graphical Abstract

INTRODUCTION

Modular cabinet systems are widely used in indoor spaces, such as homes, offices, stores, and workshops, to improve organization and enable efficient storage. These systems are typically composed of prefabricated box-type furniture elements and are manufactured with different load-bearing capacities depending on their intended use (Mokhtar et al. 2025).

Shelves may deform due to the type of material used and the weight applied. Therefore, the design of shelf support systems is crucial. Shelves are typically supported by pins made of metal, plastic, or composite materials. While metal pins are produced through turning or pressing, plastic pins are made using injection molding or extrusion techniques (Eckelman 2003; Bas et al. 2024). The appropriate selection of pins is a key factor in maintaining the durability of the system. Accordingly, mechanical performance of shelving systems manufactured from different materials is commonly assessed through a combination of experimental testing and numerical approaches, including the Finite Element Method (FEM).

Denizli et al. (2003) demonstrated that shelf deflection resistance is significantly influenced by panel thickness, material type (e.g., MDF, particleboard), and the choice of support systems. More recently, Erdinler et al. (2023) evaluated the impact of load and material density on the deflection performance of cabinet doors, reporting statistically significant findings. Slonina and Smardzewski (2022) conducted both experimental tests and finite element method (FEM) analyses on screw, nail, and eccentric connectors, revealing a high level of consistency between the two approaches. Similarly, Kłos and Langová (2023) found that screws offer superior deflection resistance compared to alternative fasteners. Eckelman (1987) and Eckelman et al. (2004) highlighted the long-term rigidity offered by mortise-and-tenon joints, while Cai and Wang (1993) successfully modeled semi-rigid corner joints using FEM, achieving high accuracy with minimal error margins. In another study, Yu et al. (2011) applied static and modal analyses through ANSYS to minimize design flaws in furniture joints. Chen and Kuo (2018) examined the relationship between shelf height and deflection, whereas Fariz et al. (2023) confirmed that a parametrically designed TV stand could safely support loads up to 100 kg. Zhang et al. (2024) improved computational efficiency by utilizing simplified FEM models for bamboo/oriented strand board (OSB) joint configurations. Li et al. (2022) performed a comparative analysis of mortise-tenon and dowel joints, and Matwiej et al. (2025) conducted stress and deformation simulations on upholstered furniture frames using FEM techniques. Furthermore, Kuskun et al. (2023) refined the design of auxetic dowels and reported that these fasteners exhibited enhanced performance compared to conventional fastening elements.

With the advancement of technology, many new materials have been integrated into production processes. In addition to applications in medical implants (Schubert et al. 2014), automobiles, and artificial organs (Ngoa et al. 2018), three-dimensional (3D) printing technology has increasingly been adopted in the furniture industry (Sun ve Zhao 2017). 3D printing offers numerous advantages, including design flexibility, waste avoidance, rapid prototyping capabilities, task-specific performance, lower material costs, lightweight construction, high-strength printed components, and the ability to produce complex and intricate geometries (Tofail et al. 2018; Islam et al. 2024). Various 3D printing technologies are available, including stereolithography (SLA), inkjet printing, and fused deposition modeling (FDM). Chacon et al. (2017) explored the impact of feed rate, build orientation, and layer thickness on the mechanical characteristics of PLA produced using affordable 3D printers. Upright samples showed lower strength due to interlayer failure, but increasing layer thickness improved strength, while higher feed rates reduced strength. Afrose et al. (2014) found that PLA printed in the X-direction had the highest tensile strength (38.6 MPa), while other orientations had lower values. Ymrak et al. (2014) reported mean tensile strength values of 28.5 MPa for acrylonitrile butadiene styrene (ABS) and 56.6 MPa for polylactic acid (PLA), accompanied by elastic moduli of 1807 MPa and 3368 MPa, respectively. PLA and ABS are among the most widely utilized filaments in fused deposition modeling (FDM) because of their satisfactory mechanical performance under diverse loading conditions. The ABS is generally characterized by its relatively high strength, whereas PLA is often preferred for its greater flexibility (Zhang et al. 2019). Moreover, combining these materials has been shown to produce components with increased strength and improved overall mechanical properties (Dizon et al. 2018). Yildirim et al. (2019) examined 3D-printed ABS and PLA dowels in fixed L-type furniture corner joints using diagonal compression tests. Dowels (8 mm diameter) were produced via FDM in both tangential and radial orientations. The MDF laminated panels coated with melamine paper were used, and joints were assembled with polyurethane adhesive. Moreover, the integration of such manufacturing technologies, along with the application of FEM simulations, has received increased attention in recent years.

Studies have shown that when 3D-printed shelf units are combined with topology optimization techniques, material usage can be significantly reduced without compromising structural integrity. For example, in a study conducted by Fenni et al. (2024), it was demonstrated that 3D-printed shelf consoles subjected to topology optimization using FEM-based static analysis achieved weight reductions of up to 70% while maintaining deflection resistance. Similarly, Gebrehiwot et al. (2024) investigated the bending stiffness of 3D-printed PLA stiffeners; it was determined that PLA parts exhibit higher bending moments compared to traditional miter joints but are not as durable as adhesive joints. These results highlight design considerations for the use of 3D-printed parts in load-bearing furniture components.

Aiman et al. (2020) conducted a comparative evaluation of furniture joints manufactured using conventional materials and production techniques versus those produced by FDM. The study concluded that joints fabricated from waste-based materials through FDM exhibited satisfactory functional performance and met acceptable quality standards. Several researchers have employed the FEM in theoretical studies aimed at optimizing object designs by eliminating stress concentration areas, thus minimizing the potential for operational failures (Santana et al. 2018; Kasal et al. 2023; Erdinler and Seker 2024).

In the furniture industry, shelving systems employ various joining techniques using materials such as plastics, metals, and composites. This study experimentally investigated the deflection response of particleboard (PB) and MDF shelves supported by pins manufactured using 3D printing technology and corroborated the experimental results using FEM simulations.

EXPERIMENTAL

Materials

Wood cabinet, shelves, and pins

Cabinets constructed from MDF and particleboard (PB), with overall dimensions of 800 mm (height), 600 mm (width), and 450 mm (depth), were randomly selected for inclusion in this study. The shelves installed in these cabinets were fabricated from MDF and PB panels with a thickness of 18 mm each. Testing was conducted on a total of 60 shelves, each representing one of the two material types. The measured density, moisture content (MC), modulus of rupture (MOR), and modulus of elasticity (MOE) values were 0.722 g/cm³, 7.02%, 29.48 N/mm², and 6130 N/mm² for MDF, and 0.65 g/cm³, 8.12%, 13.9 N/mm², and 5920 N/mm² for PB, respectively (Fig. 1).

In this study, MDF and PB shelves were mounted to cabinets using shelf pins. In shelving systems, the load-carrying capacity of the pins is typically more critical than the overall structural strength of shelves. The shelf pin configuration adopted (Fig. 2a) was chosen because it represents a design commonly employed by numerous manufacturers. These pins were redesigned using 3D printing technology and printed specifically for this study. The in-fill percentage of the 3D-printed shelf fastener was set to 50%. The filaments employed for the 3D printing process consisted of PLA and PET-G in two different colors and were supplied by a filament manufacturing company based in Turkey (Porima Polymer Technologies Inc., Yalova, Turkey), as illustrated in Figs. 2c and 2d. Samples used in the study were designed in the SolidWorks design program, and the designs saved in STL format were printed using the Creality K1 MAX device after G code assignment was made with the Creality Print 6.0 program (Fig. 2b).

Fig. 1. Representative MDF and PB shelves used in the experiments, illustrating cabinet dimensions and side-view configurations of the shelf specimens

$Preparation of the samples: a. the pin from which the sample was taken, b. the sample pin ready for printing, c. green and orange pins produced from PLA material, d. blue and gray pins produced from PETG material$

Fig. 2. Preparation of the samples: a. the pin from which the sample was taken, b. the sample pin ready for printing, c. green and orange pins produced from PLA material, d. blue and gray pins produced from PETG material

The primary objective of this study was to examine the behavior of different colors of various filament materials; thus, the 3D printer machine settings were kept constant, as shown in Table 1. The parameters that differ for PET-G and PLA filaments are also presented in Table 1.

Table 1. FDM Parameters Constant During Process

Test Method for Shelves

The experimental procedures were carried out in accordance with BS EN 16122 (2012), and TS EN 9215 (2005) was followed to determine the shelf deflection under progressively increasing loads. A test load of 80 kg/m² was applied for each 40 mm increment of the shelf length and sustained for a duration of 7 days, resulting in a total applied load of 12.8 kg. Because of the use of new materials that did not correspond to the glass, metal, or plastic categories specified in the standard, the test was performed twice. All tests were conducted under controlled laboratory conditions in accordance with ISO 554, at a temperature of 20 ± 2 °C and a relative humidity of 65 ± 5 %. The total deflection was measured at the end of the 7-day loading period. The visual documentation of each test conducted in accordance with the experimental design is presented in Table 2.

Table 2. Experimental Configurations and Visual Documentation of Shelf Deflection Tests

The initial deflection values were recorded at the midspan of the shelves prior to loading, followed by additional measurements after the application of a uniformly distributed load. The central deflection was determined using a deflection fitted with a comparator (Devotrans digital indicator) with a measurement accuracy of 0.001 mm. All measurements were conducted at the midpoint of the shelf length, corresponding to the location of the maximum deflection (Fig. 3). Under sustained loading conditions, wood and wood-based materials exhibit time-dependent viscoelastic behavior, manifested through distinct creep phases. This creep response is typically classified into three stages: primary creep, characterized by a rapid initial deformation that gradually decreases; secondary creep, marked by an approximately constant deformation rate; and tertiary creep, which involves an accelerated deformation process that ultimately leads to failure (Han et al. 2022). Although the applied weights were dimensionally rigid, they were used in accordance with the standard test setup and arranged to ensure a quasi-uniform load distribution over the shelf surface. Local contact effects were assumed to be negligible with respect to the global mid-span deflection, which governed the structural response evaluated in this study.

Fig. 3. Illustrating the shelf loading arrangement, the comparator utilized for deflection measurement, and the positioning of the pin samples

The collected data were analyzed using multivariate analysis of variance (ANOVA) tests. After identifying statistically significant differences among the groups, univariate analyses were conducted to ascertain the differences between the mean values, with the significance level set at α = 0.05. All statistical analyses were performed using the SPSS 31.0.0.0 2023 software.

In the final phase of the study, all components of the specimens, including the cabinet, shelves, and pins, were three-dimensionally modeled and assembled using SolidWorks design and assembly software (Fig. 4a). The models were developed to replicate the experimental conditions, and numerical analyses were subsequently performed using the FEM in ANSYS Workbench 21. The geometry, loading conditions, meshing process, and contacts of the shelves are illustrated in Fig. 4b. A triangular mesh structure, set at the maximum mesh density, was employed to evaluate different intervals. The MOR, density, MOE, and moisture content (MC) of the MDF and PB shelves were determined through laboratory testing, whereas the technical properties of the filaments were obtained from the manufacturer. These parameters were subsequently used to calculate the deflections of both shelf types (Fig. 4b). Additionally, the material strength under the applied loads and boundary conditions was evaluated using the safety factor method. A safety factor (SF) greater than 1 indicates that the structure is safe; an SF equal to 1 represents the limit state, and an SF less than 1 indicates an unsafe condition. The obtained results were interpreted to assess the compliance of the design with safety and performance criteria.

Fig. 4. 3D modeling and assembly of the samples: (a) complete model in SolidWorks, (b) shelf geometry, loading conditions, meshing process, and contacts

RESULTS AND DISCUSSION

In both material types (PB and MDF), the mid-span of the shelves and the regions where the pins were connected were identified as the most frequently damaged areas following the tests. During the testing process, standard loads were applied using pins produced from PLA (green, orange) and PETG (blue, grey) materials, and the deformations occurring in these regions were measured. The BS 16122 (2012) standard testing procedure was followed, and measurements were taken at 7-day intervals. After a 7-day loading period, distinct deflection responses were observed for the MDF and PB shelves. The findings indicate that the deformation levels varied depending on the type of pins used as fastening elements, and that differences in filament color and material type resulted in varying deformation behaviors (Fig. 5).

Fig. 5. Effect of pin material and filament color on shelf deflection of MDF and PB under long-term loading

According to the ANOVA results, the factors shelf material type, pin material type, and pin material color had statistically significant effects on deflection (deformation), and a Two-Way ANOVA was applied for these factors (Table 3). The analysis showed that metal pins produced the lowest deformation values for both MDF (0.7550 mm) and PB (0.8242 mm) shelf materials. Following metal pins, the group with the next lowest deformation values was the green PLA filament, with 0.7600 mm for MDF and 1.0500 mm for PB shelf material.

Table 3. Results of Two-way ANOVA for Deflection as a Function of Shelf Material and Pin Characteristics

Table 4. Mean Deflection Results for MDF and PB Shelves According to the Pin Material and Filament Color

The statistical results of the mean deflection values obtained for the variables shelf material, pin material, and pin material color are presented in Table 4.

Following the significant ANOVA result, post-hoc tests were conducted to determine which material types accounted for the differences. The Tukey HSD results showed that the METAL (M = 0.804), PLA (M = 1.002), and PET-G (M = 1.383) groups were placed in separate homogeneous subsets, indicating that all three material types differed significantly from one another (p < 0.05). The lowest value was observed in the METAL group, whereas the highest value was found in the PET-G group. The Duncan test also supported these findings. (Table 5).

Table 5. Table of Post-hoc Tests

The specimens tested under a 7-day loading period were reproduced in the ANSYS finite element analysis (FEA) environment and analyzed under identical loading conditions. The resulting deformation ranges showed close agreement with those obtained from experimental tests.

Fig. 6. Finite element analysis results showing the effect of the pin material–MDF interaction on the load–deflection behavior

The static load analysis performed on the four pins supporting the cabinet shelf was found to be consistent with the experimental results. For MDF shelves, the maximum deformation observed in PLA pins was 0.73 mm for PLA Green and 0.93 mm for PLA Orange. Although PETG materials possess higher stiffness compared to PLA, they exhibited greater deformation, with PETG Grey and PETG Blue reaching 0.99 mm and 1.39 mm, respectively. Metal pins, in contrast, demonstrated the lowest deformation at 0.66 mm, reflecting minimal displacement due to the material’s high elastic modulus. These variations can be attributed to the interaction between the pin material and the MDF substrate, where differences in load transfer efficiency, stiffness, and material brittleness affect the overall deformation behavior (Fig. 6).

For PB shelves, the maximum deformation observed in PLA pins was 1.03 mm for PLA Green and 1.29 mm for PLA Orange. The PETG pins exhibited deformations of 1.26 mm for PETG Grey and 1.79 mm for PETG Blue, despite their higher stiffness relative to PLA. Metal pins showed the lowest deformation at 0.83 mm. The increased deformations compared to MDF shelves can be attributed to the lower density and heterogeneity of particleboard, which reduce its load-bearing capacity and result in greater deflection under identical loading conditions. The differences in pin material properties and the interaction with the PB substrate further influence the overall deformation behavior (Fig. 7).

Fig. 7. Finite element analysis results showing the effect of the pin material–PB interaction on the load–deflection behavior

The SF analysis results revealed that PB and MDF exhibited significantly different safety performances depending on the type of pin used. In shelves with PLA pins, PB panels displayed extensive yellow–orange zones in central regions due to their lower strength, with safety factors approaching critical values, whereas MDF shelves showed reduced stress but SF remained at limited levels in central areas. For gray PETG pins, safety factors decreased further in PB panels compared to PLA, increasing structural risk, while MDF panels maintained moderate but acceptable safety performance.