The Impact of Dovetail Angle in Single Dovetail Joints on Diagonal Compression Strength of Corner Joints for Box-Type Furniture

Abstract This study aims to determine the impacts of dovetail angle for dovetail joints on the diagonal compression strength of box-type furniture corner joints prepared in different woods, with different dovetail angles, and with different adhesives. For this reason, after drilling joints of 75°, 78°, 81°, 84°, and 87° on Oriental beech, European oak, Scotch pine, and medium-density fiberboard (MDF) samples, a diagonal compression test was applied on corners glued with polyvinyl acetate (PVAc) and polyurethane (Desmodur-vinyl trieketonol acetate [D-VTKA]) according to the ASTM D1037 standard. The highest result for dovetail diagonal compression strength was observed in the samples of Oriental beech (0.321 N mm−2), while the lowest was found in the samples of MDF (0.154 N mm−2) for wood types. With respect to adhesives, D-VTKA yielded the best results (0.268 N mm−2), while PVAc gave the worst results (0.252 N mm−2). Regarding angle types, the best result was obtained from the samples at 84° (0.302 N mm−2) and the worst from the samples at 75° (0.207 N mm−2) for dovetail joints. For the interaction of wood type, adhesive, and dovetail angle, the highest diagonal compression strength was found in the samples of Oriental beech + 81° + D-VTKA (0.445 N mm−2), while the lowest value was observed in MDF + 78° + D-VTKA (0.128 N mm−2). In conclusion, the angles and adhesives have significant effects on the corner joints of box-type furniture.

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Impact of pressing regime and substrate type on bond quality of decorative veneer

BioResources ◽

10.15376/biores.15.2.2668-2679 ◽

2020 ◽

Vol 15 (2) ◽

pp. 2668-2679

Author(s):

Vladislav Zdravković ◽

Tanja Palija ◽

Aleksandar Lovrić ◽

Anđela Obradović

Keyword(s):

Multivariate Analysis ◽

Bond Strength ◽

Urea Formaldehyde ◽

Medium Density Fiberboard ◽

Medium Density ◽

Substrate Type ◽

Bond Quality ◽

The Impact ◽

Moisture Resistant

The choice of optimal pressing regime for certain types of substrate is of great importance in production of veneered panels. In this paper, the impact of pressing regime on the bonding strength of beech and oak veneers, glued with urea-formaldehyde (UF) adhesive, on medium-density fiberboard (MDF), and moisture-resistant MDF (MR MDF) substrates was examined. The analyses showed a generally higher bond strength with oak veneer compared to beech veneer, which was also the case with regular MDF compared to moisture-resistant MDF. Multivariate analysis of variance (ANOVA) showed that with beech veneer, all of the used regimes produced better results on regular MDF compared to moisture-resistant MDF. In contrast, with oak veneer, the influence of pressing regime had a more noteworthy impact than the type of substrate used. These results indicated that the use of MR MDF as substrate in combination with UF adhesive was inadequate.

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Research into Corner L Separable Assemblies in Storage Furniture

Drvna industrija ◽

10.5552/drvind.2021.1924 ◽

2021 ◽

Vol 72 (1) ◽

pp. 89-98

Author(s):

Ivica Župčić ◽

Ivan Žulj ◽

Igor Kamerman ◽

Ivica Grbac ◽

Zoran Vlaović

Keyword(s):

Joint Strength ◽

Medium Density Fiberboard ◽

Bending Moment ◽

Trade Mark ◽

The Other ◽

Medium Density ◽

Research Results ◽

Other Hand ◽

Wear And Tear ◽

The Impact

This research is based on the testing of the impact of the board (particleboard and medium density fiberboard (MDF)) and hardware type used to connect the sides and the bottom or top of the storage furniture on the joint strength. The hardwares of the following trade mark were used: the confirmat screw, Minifix, Maxifix, Stablofix, RV and Solo 32. Such hardwares make it possible to disassemble the furniture as well as to assemble it (when moving the furniture) without reducing joint strength when reassembling it due to wear and tear on the material (with the exception of the confirmant screw). Research results showed that assemblies with the Maxifix hardware installed in the MDF base exhibited the highest values of bending moment (the average bending moment of 85.88 Nm). On the other hand, assemblies with the Minifix hardware installed in the particleboard exhibited the lowest values of bending moment (over three times lower than the Maxifix) (the average bending moment of 24.50 Nm). Assemblies with the confirmat screw exhibited satisfactory results, although, aesthetic requirements seem to be the main problem here (the average bending moment of 40.38 Nm for the particleboard and of 64.24 Nm for the MDF).

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Method development for the determination of textural properties of sugar beet roots

Sugar Industry ◽

10.36961/si23306 ◽

2019 ◽

pp. 392-400 ◽

Cited By ~ 2

Author(s):

Gunnar Kleuker ◽

Christa M. Hoffmann

Keyword(s):

Sugar Beet ◽

Compression Test ◽

Storage Period ◽

Textural Properties ◽

Small Sample ◽

Root Tip ◽

Flexural Test ◽

Sample Distribution ◽

The Impact

The harvest of sugar beet leads to root tip breakage and surface damage through mechanical impacts, which increase storage losses. For the determination of textural properties of sugar beet roots with a texture analyzer a reliable method description is missing. This study aimed to evaluate the impact of washing, soil tare, storage period from washing until measurement, sample distribution and number of roots on puncture and compression measurements. For this purpose, in 2017 comprehensive tests were conducted with sugar beet roots grown in a greenhouse. In a second step these tests were carried out with different Beta varieties from a field trial, and in addition, a flexural test was included. Results show that the storage period after washing and the sample distribution had an influence on the puncture and compression strength. It is suggested to wash the roots by hand before the measurement and to determine the strength no later than 48 h after washing. For reliable and comparable results a radial distribution of measurement points around the widest circumference of the root is recommended for the puncture test. The sample position of the compression test had an influence on the compressive strength and therefore, needs to be clearly defined. For the puncture and the compression test it was possible to achieve stable results with a small sample size, but with increasing heterogeneity of the plant stand a higher number of roots is required. The flexural test showed a high variability and is, therefore, not recommended for the analysis of sugar beet textural properties.

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Calcium carbonate modified urea–formaldehyde resin adhesive for strength enhanced medium density fiberboard production

RSC Advances ◽

10.1039/d1ra04316a ◽

2021 ◽

Vol 11 (40) ◽

pp. 25010-25017

Author(s):

Li Lu ◽

Yan Wang ◽

Tianhua Li ◽

Supeng Wang ◽

Shoulu Yang ◽

...

Keyword(s):

Calcium Carbonate ◽

Urea Formaldehyde ◽

Medium Density Fiberboard ◽

Urea Formaldehyde Resin ◽

Formaldehyde Resin ◽

Medium Density ◽

Ionic Bond ◽

Resin Adhesive ◽

Uf Resin ◽

Modified Urea

Reactions between CaCO3 and CH2O2 during polycondensation of UF resin produce Ca2+. Ionic bond complexation binds Ca2+ with UF resin. The UF resin crystalline percentage decreases from 26.86% to 22.71%. IB strength of resin bonded fiberboard increases from 0.75 to 0.94 MPa.

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Study on improvement of prefolded energy absorption device to constant resistance and its mechanical properties

Science Progress ◽

10.1177/00368504211036820 ◽

2021 ◽

Vol 104 (3) ◽

pp. 003685042110368

Author(s):

Dong An ◽

Jiaqi Song ◽

Hailiang Xu ◽

Jingzong Zhang ◽

Yimin Song ◽

...

Keyword(s):

Mechanical Properties ◽

Energy Absorption ◽

Compression Test ◽

Side Wall ◽

Concave Side ◽

Displacement Curve ◽

Static Compression ◽

Constant Resistance ◽

The Impact ◽

Force Displacement

When the rock burst occurs, energy absorption support is an important method to solve the impact failure. To achieve constant resistance performance of energy absorption device, as an important component of the support, the mechanical properties of one kind of prefolded tube is analyzed by quasi-static compression test. The deformation process of compression test is simulated by ABAQUS and plastic strain nephogram of the numerical model are studied. It is found that the main factors affecting the fluctuation of force-displacement curve is the stiffness of concave side wall. The original tube is improved to constant resistance by changing the side wall. The friction coefficient affects the folding order and form of the energy absorbing device. Lifting the concave side wall stiffness can improve the overall stiffness of energy absorption device and slow down the falling section of force-displacement curve. It is always squeezed by adjacent convex side wall in the process of folding, with large plastic deformation. Compared with the original one, the improved prefolded tube designed in this paper can keep the maximum bearing capacity ( Pmax), increase the total energy absorption ( E), improve the specific energy absorption (SEA), and decrease the variance ( S2) of force-displacement curve.

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