The need for rapid, low-cost die fabrication and modification methods is greater than ever in the sheet metal forming sector of industry. Consequently, three fabrication methods, suitable for rapid die development schemes, are being compared experimentally based on cost, lead-time, shape resolution and flexibility issues. The candidate methods include CNC-machining a solid billet of material (standard method), assembling and clamping an array of profiled-edge laminations (PEL), and configuring and clamping a matrix of closely-packed pins (discrete die). A matched-set of forming dies was made using each of the candidate fabrication methods for stamping an FEA-verified benchmark part out of steel sheet. Based on the stamping experiments, a PEL die is shown to be similar to CNC-machined dies except that most tooling accessibility problems are eliminated, die geometry limitations are reduced and faster fabrication is possible for harder tool materials. When compared with CNC-machined dies, the discrete die method limits part shape fidelity, maximum forming loads, die geometry and blankholder incorporation. However, the discrete die method excels over the other two methods in terms of lower cost and faster fabrication time. The results of this study make a strong case for the sheet metal forming sector of industry to actively implement the PEL and discrete die methods in their manufacturing operations.

1.
Aubin, R. F., 1994, “A World Wide Assessment of Rapid Prototyping Technologies,” UTRC Report No. 94-13, United Technologies Research Center, East Hartford, CT, Jan.
2.
Dastidar, P., 1995, Senior Engineer, Advanced Manufacturing, Carrier Corporation, Syracuse, New York, Personal Conversation on May 16, 1995.
3.
Dickens, P., Simon, D., and Sketch, R., 1996, “Laminated Tooling for Moulding Polyurethane Parts,” Proceedings of the SME Conference on Rapid Prototyping and Manufacturing, Dearborn, MI, April 22–25.
4.
Eigen, G. F., 1992, Smoothing Methods for Discrete Die Forming, M.S. Thesis, Dept. of Mechanical Engineering, MIT, June.
5.
Engler, I., Schubert, E., and Sepold, G., 1997, “Direct Metal Prototyping with the LASP Technology,” Proceedings of the International Conference NNS (Near Net Shape) ’97, Bremen, Germany, April 14–16, pp. 335–341.
6.
FMA Member Resource Directory, 1994, Fabricators & Manufacturers Association, Chicago, Illinois.
7.
Glozer
G. R.
, and
Brevick
J. R.
,
1992
, “
Laminate Tooling for Injection Moulding
,”
Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture
, Vol.
207
, pp.
9
15
.
8.
Hardt, D. E., and Webb, R. D., 1982, “Sheet Metal Die Forming Using Closed-Loop Shape Control,” Annals of CIRP, pp. 165–169.
9.
Horner, A. H., 1995, Office Manager, Gilbert & Richards, Inc., North Haven, Connecticut, Memorandum dated Feb. 22, 1995.
10.
Karafillis, A. P., and Boyce, M. C., 1992, “Tooling Design in Sheet Metal Forming Using Springback Calculations,” International Journal of Mechanical Sciences, Vol. 113, No. 34.
11.
Karafillis, A. P., 1994, Tooling Design for Three-Dimensional Sheet Metal Forming Using Finite-Element Analysis, Ph.D. Thesis, Dept. of Mechanical Engineering, MIT, August.
12.
Kunieda, M., and Nakagawa, T., 1984, “Manufacturing of Laminated Deep Drawing Dies by Laser Beam Cutting,” Proceedings of the 1st International Conference on Technology of Plasticity, Vol. 1, Tokyo, Japan, pp. 520–524.
13.
Nakagawa
T.
,
1994
, “
Recent Manufacturing Technologies for Auto-Body Panel Forming Tools
,”
Journal of Materials Processing Technology
, Vol.
46
, pp.
277
290
.
14.
Nardiello, J. A., 1995, Senior Engineer, Advanced Technology and Development Center, Northrop Grumman Corp., Bethpage, New York, Memorandum on March 28, 1995.
15.
Oberg, E., Jones, F. D., and Horton, H. L., 1988, Machinery’s Handbook, 23rd Edition, Industrial Press, New York.
16.
Ousterhout, K. B., 1991, Design and Control of a Flexible Process for Three-Dimensional Sheet Metal Forming, Ph.D. Thesis, Dept. of Mechanical Engineering, Massachusetts Institute of Technology.
17.
Pridham, M. S., and Thomson, G., 1993, “Part Fabrication Using Laser Machining and Welding,” Proceedings of the Fourth Solid Freeform Fabrication Conference, Austin, TX, August, pp. 74–80.
18.
Raja
J.
, and
Radhakrishnan
V.
,
1997
, “
Analysis and Synthesis of Surface Profiles Using Fourier Series
,”
International Journal of Machine Tool Design & Research
, Vol.
19
, pp.
245
251
.
19.
Semiatin, S. L., et al., 1988, Metals Handbook: Volume 14, Forming and Forging, Ninth Edition, ASM International, Metals Park, Ohio.
20.
Shigley, J. E., and Mitchell, L. D., 1983, Mechanical Engineering Design, 4th edition, McGraw-Hill, New York.
21.
Siekirk
J. F.
,
1986
, “
Process Variable Effects on Sheet Metal Quality
,”
Journal of Applied Metalworking
, Vol.
4
, No.
3
, July, pp.
262
269
.
22.
Shigley, J. E., and Mitchell, L. D., Mechanical Engineering Design, 4th edition, McGraw-Hill, New York.
23.
Wagner, R., 1995, Die Cost Estimator, Autodie International, Inc., Grand Rapids, Michigan, Personal Conversation on May 22, 1995.
24.
Walczyk, D. F., and Hardt, D. E., 1994, “A New Rapid Tooling Method for Sheet Metal Forming Dies,” Proceedings of the Fifth International Conference on Rapid Prototyping, Dayton, Ohio, June 12–15, pp. 275–289.
25.
Walczyk, D. F., 1996, “Rapid Fabrication Methods for Sheet Metal Forming Dies,” PhD Thesis, Dept. of Mechanical Engineering, Massachusetts Institute of Technology.
26.
Walker, D. C., 1993, “Design of a Process Improvement Methodology for Die Construction,” M.S. Thesis, Dept. of Mechanical Engineering, Massachusetts Institute of Technology, June.
27.
Webb, R. D., and Hardt, D. E., 1991, “A Transfer Function Description of Sheet Metal Forming for Process Control,” ASME JOURNAL OF ENGINEERING FOR INDUSTRY, Vol. 133, No. 44.
28.
Womack, J. P., Jones, D. T., and Roos, D., 1991, The Machine That Changed The World, Harper Perennial, New York.
This content is only available via PDF.
You do not currently have access to this content.