Effect of Tool Path Strategies in Pocket Milling of Aluminium Epoxy

2014 ◽  
Vol 903 ◽  
pp. 15-20 ◽  
Author(s):  
Rusdi Mat Song ◽  
Safian Sharif ◽  
Ahmad Yasir Md Said ◽  
Mohd Tanwyn Mohd Khushairi

Selection of the most suitable tool path strategy is very essential during machining especially in computer aided design and manufacture (CAD/CAM) as well as computer numerical control (CNC) machining. Existence of various tool path strategies to be applied on advanced composite materials such as aluminium epoxy required extensive researches in determining the best combination of tool path and cutting parameters for better machinability performance. Pocket milling of aluminium epoxy specimen via CAD/CAM was conducted in this study to investigate the effect of three types of tool path strategies namely Inward Helical, Outward Helical and Back and Forth. Uncoated high speed steel (HSS-Co8) ball end mill was used throughout the experiments. The machining responses that were evaluated include machining time, tool wear rate, tool life and surface finish of the machined pockets. In general, the effect of tool path strategy was highly significant on the machining responses and results showed that Back and Forth strategy offered the best machinability results when compared to the other strategies.

2005 ◽  
Vol 291-292 ◽  
pp. 625-630
Author(s):  
Min Jie Wang ◽  
Y.J. Cai ◽  
W.G. Yan

Sculptured surface machining is a critical process commonly used in die and mold industries. Since there is a lack of scientific tools in practical process planning stages, feedrates of CNC machining are selected based on previous experiences. In the selection of feedrate, the feedrate is set an individual conservative constant value all along the die cavity roughing processes in order to avoid undesirable results such as chipping, cutter breakage or over-cut due to excessive cutter deflection. Usually, volumetric models or vector force models used for optimizaton of feedrates must be created to get the variable feedrates along the tool path. Considering the die cavity roughing being a 2.5D cutting, a novel cutting force surface model is created based on orthogonal cutting tests to adjust the feedrates. The model is tested by a typical die-cavity roughing, thinning down machining time and balanced cutting-load can be attained. The presented feedrate scheduling characterized by balancing the cutting-loads in die-cavity roughing will be more significative in high speed machining.


Author(s):  
H S Choy ◽  
K W Chan

Tool path generation based on contour-parallel offset has many practical applications, especially in pocket milling. However, the tool path segments offset from the pocket boundary usually form many corners. In milling operation, these corners with accumulated material will have an adverse effect on milling performance. This paper proposes an improved numerically controlled (NC) tool path pattern for pocket milling. Bow-like tool path segments are appended to a conventional contour-parallel tool path at the corner positions. The cutter loops along the appended tool path so that the corner material is machined progressively in several passes. By adjusting the number of appended tool path loops, cutting resistance can be controlled. The proposed tool path generation for dealing with different corner shapes was implemented as an addon user function in a computer aided design/manufacture (CAD/CAM) system. Cutting tests confirmed that the proposed tool path pattern is useful for clearing accumulated material at pocket corners while maintaining a higher cutting stability.


2017 ◽  
Vol 42 (5) ◽  
pp. E6 ◽  
Author(s):  
William T. Couldwell ◽  
Joel D. MacDonald ◽  
Charles L. Thomas ◽  
Bradley C. Hansen ◽  
Aniruddha Lapalikar ◽  
...  

The authors have developed a simple device for computer-aided design/computer-aided manufacturing (CAD-CAM) that uses an image-guided system to define a cutting tool path that is shared with a surgical machining system for drilling bone. Information from 2D images (obtained via CT and MRI) is transmitted to a processor that produces a 3D image. The processor generates code defining an optimized cutting tool path, which is sent to a surgical machining system that can drill the desired portion of bone. This tool has applications for bone removal in both cranial and spine neurosurgical approaches. Such applications have the potential to reduce surgical time and associated complications such as infection or blood loss. The device enables rapid removal of bone within 1 mm of vital structures. The validity of such a machining tool is exemplified in the rapid (< 3 minutes machining time) and accurate removal of bone for transtemporal (for example, translabyrinthine) approaches.


2013 ◽  
Vol 584 ◽  
pp. 149-153
Author(s):  
Jing Chuan Dong ◽  
Tai Yong Wang ◽  
Yan Yu Ding ◽  
Yu Long Cui

The computerized numerical control (CNC) machining program usually contains a large number of small line segments. The CNC controller must generate a smooth and optimized motion profile to achieve high speed and high precision machining. This paper proposed an adaptive contour error control algorithm. The curvature radius of the tool path is obtained by analyzing the geometry relationship. The algorithm uses the curvature information and a simplified servo error model to realize contour error estimation and adaptive control. The target feet rate filter (TFF) and planning unit merging (PUM) are introduced to obtain a smooth profile. Experiments result demonstrated the efficiency of the proposed algorithm.


2012 ◽  
Vol 542-543 ◽  
pp. 1167-1171
Author(s):  
Chun Wang ◽  
Sheng Lin ◽  
Quan Hai Peng

Tool radius compensation is necessary to CNC machining. However, B tool radius compensation leads to work piece burning at the sharp corner of convex contour because of the long time contacts between the work piece and tool, and C tool radius compensation frequently changes machining feed rate for its broken line tool path. This paper presents a novel tool radius compensation method suitable for high speed machining of convex contour, which have the advantages of both B and C tool radius compensation. It uses compound transition with line and arc between the adjacent blocks of CNC program. The offset tool paths of the adjacent blocks extend a small line segment respectively along their tangent direction, then insert an arc between the end points of the two extended line segments. The results of simulation and experiments show that the machining quality of the sharp corner of convex contour is improved and the machining time is shorter than C tool radius compensation.


2013 ◽  
Vol 581 ◽  
pp. 478-484 ◽  
Author(s):  
Sergey N. Grigoriev ◽  
Andrey A. Kutin ◽  
Mikhail Turkin

This paper presents a method to simultaneously increase the accuracy and decrease the calculation time for complex tool path programming in multi-axis machining centers. Examples of complex parts requiring such complex tool paths include various kinds of turbine blades, pump-forcing augers, teeth surfaces, etc. It explains the creation of topological structures on the basis of analytical spline curves with floating range definitions. The method for tool path calculation accommodates the specific requirements for multi-axis milling. The algorithms developed are the foundation for the CAD/CAM software that allows for NC programming and machining on 5-axis centers employing any design model. Industrial tests reveal a 70-80% reduction of NC programming time of parts with complex surfaces, reduced machining time of approximately 40-50% using basic high-speed cutting methods and custom-made tools. The advanced methods of NC programming result in substantially increasing machining accuracy.


2011 ◽  
Vol 175 ◽  
pp. 121-125
Author(s):  
Ning Ning Zhang ◽  
Chen Jiang ◽  
Zhen Zhong Wang ◽  
Yin Biao Guo

Large scale wedge/aspheric lens element is a combination of wedge prism and aspheric lens as a single piece component forming a decentred lens, which is primarily manufactured by Computerized Numerical Control (CNC) machining, especially 3-axis CNC grinding. This paper presents an efficient tool path generation approach based on isophote interpolation. The interpolation guarantees that interpolated points always stay on the iso-inclination curve of the parametric surface. This symmetry ensures that the method can improve and automate large scale wedge/aspheric lens element machining for 3-axis CAD/CAM systems. As part of the validation process, the tool paths generated are analyzed and compare with the desired part.


2012 ◽  
Vol 150 ◽  
pp. 235-239
Author(s):  
Jin Gui Wan ◽  
Xi Ping Wang ◽  
Wei Ding ◽  
Wei Li

Based on UG II CAD/CAM system, the CNC machining process and technology of a toy car cover is studied in this paper. It includes three-dimension (3D) modeling, machining programming, fixture design and manufacturing, process parameter setting, tool path planning and editing, NC code generation (post processing), simulation processing, and practical machining. The part is manufactured successfully in a 3-axis CNC milling machine. It has a desirable shape and high accuracy. The result shows that, with the powerful CAD/CAM capabilities of UG, the integrated design and manufacturing of complex curved surface shell part is easy to implement, the process is reasonable and efficient, and the NC program is reliable. This exmple fully reflects the advantages of UG CAD/CAM integration technology. The method and technology introduced in this paper can provide valuable reference for processing of similar parts.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3819
Author(s):  
Ting-Hsun Lan ◽  
Yu-Feng Chen ◽  
Yen-Yun Wang ◽  
Mitch M. C. Chou

The computer-aided design/computer-aided manufacturing (CAD/CAM) fabrication technique has become one of the hottest topics in the dental field. This technology can be applied to fixed partial dentures, removable dentures, and implant prostheses. This study aimed to evaluate the feasibility of NaCaPO4-blended zirconia as a new CAD/CAM material. Eleven different proportional samples of zirconia and NaCaPO4 (xZyN) were prepared and characterized by X-ray diffractometry (XRD) and Vickers microhardness, and the milling property of these new samples was tested via a digital optical microscope. After calcination at 950 °C for 4 h, XRD results showed that the intensity of tetragonal ZrO2 gradually decreased with an increase in the content of NaCaPO4. Furthermore, with the increase in NaCaPO4 content, the sintering became more obvious, which improved the densification of the sintered body and reduced its porosity. Specimens went through milling by a computer numerical control (CNC) machine, and the marginal integrity revealed that being sintered at 1350 °C was better than being sintered at 950 °C. Moreover, 7Z3N showed better marginal fit than that of 6Z4N among thirty-six samples when sintered at 1350 °C (p < 0.05). The milling test results revealed that 7Z3N could be a new CAD/CAM material for dental restoration use in the future.


Author(s):  
Mandeep Dhanda ◽  
Aman Kukreja ◽  
SS Pande

This paper reports a novel method to generate adaptive spiral tool path for the CNC machining of complex sculptured surface represented in the form of cloud of points without the need for surface fitting. The algorithm initially uses uniform 2 D circular mesh-grid to compute the cutter location (CL) points by applying the tool inverse offset method (IOM). These CL points are refined adaptively till the surface form errors converge below the prescribed tolerance limits in both circumferential and radial directions. They are further refined to eliminate the redundancy in machining and generate optimum region wise tool path to minimize the tool lifts. The NC part programs generated by our algorithm were widely tested for different case studies using the commercial CNC simulator as well as by the actual machining trial. Finally, a comparative study was done between our developed system and the commercial CAM software. The results showed that our system is more efficient and robust in terms of the obtained surface quality, productivity, and memory requirement.


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