At a recent PMA-sponsored deep draw seminar, some of the best brains in the industry were invited to demonstrate samples of their work. An informal panel of peers was asked to judge the samples. As it happens, the "winner" was an exceptionally deep drawn part from Risdon (photo below on the left). Actually, all of the parts were winners in that they pushed the frontiers of deep drawing technology just a little further. Here, not in any order of merit, are eight of the best.

This thermostat body is produced by Risdon Corp., Fabricated Products Division, Naugatuck, CT. The quantities are very substantial. It was originally made from copper tubing and required a number of operations including cut-off, forming a flange, redraw, spin forming and soldering of the bottom.

It is now produced as a deep drawn eyelet part on a modified Waterbury Farrel No. 2012 eyelet machine in 20 stations at a substantial cost savings and with an improvement in overall quality. The critical characteristics that control the function of the part are overall length, roundness and a 12 mu-in. finish on the inside diameter.

The part is made from 0.046 in. thick copper and the minimum wall thickness at any given point is 0.028 in. Overall length of the part is 4.959 in. and roundness is held to within 0.011 TIR. The draw ratio is about 20 to 1.

Although it looks like a classic transfer press job, this part is produced on a 300-ton Minster straight-side press by Progressive Metal Forming, Inc., Hamburg, MI. A rather large part-the height is 2 ½ in. and the major diameter is 2 in.-it is produced from 300 Series stainless steel 0.038 in. thick and is held to exacting tolerances ranging from 0.002 in. to 0.010 in. Quantities total 100,000 monthly.

PMF uses a special transfer unit of its own design. The unit has 12 stations and 10 of them are used to produce this part. One of the most difficult features of the part design is the square window which can be seen at right.

Progressive achieves it by incorporating a cam-driven tool in one of the final stations in the die. It produces a remarkable clean edge with minimal die break or burr. Note the lack of draw marks.

This part is a pilot sleeve for a throw-out bearing assembly and it was designed by Joe Hartline of the Torrington Co., Torrington, CT, in the company's Clinton, SC, plant. It's made from 0.040 in. thick 1012 steel in part runs of 5,000 pieces.

It has been produced in both a Waterbury Farrel PC 210 and a No. 1211 transfer press, using 10 stations. The sequence of operations includes blank, cup, first redraw, 2nd redraw, 3rd redraw, size bottom diameter (critical), flatten top section, size top diameter, clip top and, finally, pierce bottom.

The Clinton plant specialized in relatively deep draws involving fairly thick material. The body of the pilot sleeve shows virtually no scuff or draw marks. Even so, Joe Hartline plans to investigate several tool polishing techniques he heard discussed at the deep drawing seminar and to evaluate several new types of synthetic lubricants also discussed at the seminar.

The photograph doesn't do justice to this assembly which actually is finished to a high gloss by vacuum metalizing. It is composed of three parts; a top shell, a center shell and a bottom shell. All are produced on a Waterbury Farrel ICOP machine by Specialty Packaging Co., Waterbury, CT.

The part is a candle stick which also does double duty as a cologne container. It is highly decorative with debossed semi-ovals and patterns. The first part, the top shell, requires eight stations; the second part, the center shell, requires 13 including escape and the third part, the bottom shell, requires 13 additional stations including six draws and a tricky operation involving turning a flange.

The material is 5050-0 aluminum. It is bought in thicknesses of 0.015 and 0.020 in., in both cases plus or minus 0.00075 in. Although it's primarily a decorative part, tolerances are tight.

The latch housing at right is a redesign of the assembly at left and it performs exactly the same functions although it is made in one piece by Trans-Matic Mfg. Co., Holland, MI. The parts are produced on a No. 15 Waterbury Farrel transfer press with 13 working stations.

The tooling includes an outward lance, reconing, turning the part over 180 deg. and later rotating it 90 deg. Four holes in the side wall and five notches at the open end are produced by cam-actuated, side motion cutting tools.