<p>Prosthetic arm designed for trans-radial amputees. Upper arm parts are still to come. Parts are very small, I recommend printing them at at least 180% maybe 240% for an adult. The finger joints can be printed on their sides, just make sure they are printed with the connecting male/female parts facing up in order to avoid needing any support structure.<br></p><p><i>Finger 1 (*5)</i> - first finger joint</p><p><i>Finger 2 (*4)</i> - second finger joint</p><p><i>Finger 3 (*4)</i> - third finger joint</p><p><i>Thumb 1 (*1) - </i>first thumb joint</p><p><i>Thumb 2 (1*) - </i>Second thumb joint<br></p><p>Thread an elastic string (~6") Through the top of in each finger and down through the palm, tie it off tightly at both ends.</p><p>Thread a strong and thin non-elastic string (~18") through the bottom set of holes. Tie it off at the finger tip (I usually tie it around the base of the elastic knot at the finger tip)</p><p>Gorilla Glue (or some kind of strong glue like Rez n Bond) <i>nub </i>into <i>upper arm </i>and <i>arm cup p1 </i>to <i>arm cup p2</i></p><p><i></i>Try to keep the tension as similar as possible and tie all the the strings around around <i>nub </i>with a little bit of tension (just enough that the fingers are very slightly bent)<br></p><p>When you pull the plain strings (bend elbow) coming out of the base of the palm, the hand should close.</p><p>--- <b>UPDATE:</b> I've stopped threading regular string through the thumb (but still use elastic), it works better rigid ---</p><p>--- Fairing can replace arm cup p1 ---</p><p>*number needed for full hand</p><p><b>Please note, This arm is not extensively tested</b></p>
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