Prosthetic Arm Force Reducer Team 1 – Halliday's ... - Ohio University

7.2.1 Rings (Part #’s THH-001 [Elbow] & THH-001 [Wrist])
1) Obtain 2.5 OD 2.0 ID 304 Stainless tube.
2) Face off front of tube to ensure square face.
3) Turn down to 2.28 OD for front ring and 2.45 for back ring.
4) Place 5 degree chamfer .1 inch from front.
5) Cut off ring at .5 inch long.
6) Mill .275 flat on the x axis 0 degrees relative to ring. The flats will be .01 down on the z
axis.
7) Center flat and use start drill .2 inches from front of ring (y axis). For the back ring it is
.2 inches from the back of the ring.
8) Drill hole with number 3 drill bit.
9) Tap hole with ¼ 28 threads per inch tap.
10) Repeat steps 6-9 at 90, 180, and 270 degrees relative to ring.
7.2.2 Track (2x) (Part # THH-003)
Figure 7.2.1. - Ring Manufacture
1) Cut ½ x ½ box steel to approximately 3 inches using band saw.
2) Mill sides so square and overall length in 2 29/32 inches.
3) Center box steel on y axis and start drill .2 inches from outer edge.
4) Drill mounting holes with 9/32 inch bit.
5) Repeat steps 3-4 on other side of the box steel.
6) Flip box so the holes now are facing downward.
7) Mill .45 back on x axis from face of box.
8) Repeat passes with an increase in depth until thickness of track is only .1 inch.
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