CNC Pliers

Here's a pair of pliers made from 1/4" thick aluminum plate. Designed as a CNC project, you could also (patiently) make them on a manual machine. The two pieces are identical and are held together with a short (~.3") piece of 1/4" brass rod that is peened over. The interlocking area is .125" deep. 

Before building a successful model, we built several prototypes, including a "wood trace" model (seen in the left side of the photo below).

The print below shows the general layout of the pliers.

General dimensions are seen in the print below.

The toolpath can be seen in the print below. Note that our "origin" (0,0,0) for the program started at the "nose" of the plier. We used a 1/4" diameter center-cutting two-flute end mill. This allowed us to drill the hinge hole with out a tool change. The actual CNC program cuts the outline and the interlock area to a depth of .125" (actually, "Z-.125"). Then the hinge hole is drilled through (to "Z-.3"). Finally, the outer profile is cut a little more than 1/4" (actually "Z-.27") and the piece falls out of the plate (we used 3" X 1/4" plate).

 

The actual CNC code is seen below. We used our "PowerStation" CNC post-processing software to generate this code from an AutoCAD "dxf" file. Note that the feed rate here is shown as "5" (inches per minute). You might go a bit slower on the first prove-out.

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O1000

N10 G20 G40

N20 S2000 M3

N30 G0 X0 Y0 Z1.

N40 G0 Z1.

N50 X.1804 Y-.2053

N60 G01 Z-.125 F5.

N70 X1.3718

N80 X2.553 Y.3399

N90 X4.8765 Y.4111

N100 Y.411

N110 G3 X5.1265 Y.6688 R.2579

N120 G1 Y.9389

N130 G3 X4.8686 Y1.1968 R.2579

N140 G1 X2.6692

N150 X1.5838 Y1.0181

N160 X1.02

N170 X.6505 Y.6486

N180 Y.4114

N190 G2 X.5755 Y.4324 R-.044

N200 G1 X-.2283 Y.5027

N210 X.1804 Y-.2053

N220 X.8713

N230 Y.1162

N240 X.8039 Y.1836

N250 X.9005 Y.5451

N260 X1.1235 Y.7681

N270 X1.5666

N280 X2.2254 Y.464

N290 X1.3169 Y.0447

N300 X.8713

N310 X.6831 Y.3034

N320 X.755 Y.5158

N330 X1.0734 Y.8091

N340 X1.4433 Y.8294

N350 X2.37 Y.354

N360 X1.433 Y-.0405

N370 X.981 Y-.0709

N380 X.9707 Y.3641

N390 X1.32 Y.6271

N400 X2.0494 Y.3843

N410 X1.433 Y.182

N420 X1.0734 Y.1517

N430 X1.2994 Y.4045

N440 X1.7925 Y.354

N450 X1.4946 Y.3135

N460 X1.2584 Y.3438

N470 X1.25 Y.343

N480 Z-.3

N490 Z.25

N500 X.1804 Y-.2053

N510 G1 Z-.27 F5.

N520 X1.3718

N530 X2.553 Y.3399

N540 X4.8765 Y.4111

N550 Y.411

N560 G3 X5.1265 Y.6688 R.2579

N570 G1 Y.9389

N580 G3 X4.8686 Y1.1968 R.2579

N590 G1 X2.6692

N600 X1.5838 Y1.0181

N610 X1.02

N620 X.6505 Y.6486

N630 Y.4114

N640 G2 X.5755 Y.4324 R-.044

N650 G1 X-.2283 Y.5027

N660 X.1804 Y-.2053

N670 G0 Z1.

N680 X0. Y0.

N690 G0 X0Y0Z1.0

N700 M5

N710 M30

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