+
+slop=0.5;
+
+prongthick=5;
+prongwidth=5;
+ratchetstep=10;
+ratchettooth=3;
+ratchettoothheight=5;
+overlap=0.5;
+
+armendwallthick=2.5;
+armendbasethick=1.2;
+
+module ArmEnd(length=100){
+ channelwidth = prongthick + slop;
+ channeldepth = prongwidth + ratchettoothheight;
+ totalwidth = armendwallthick*2 + channelwidth;
+ totalheight = channeldepth + armendbasethick;
+ difference(){
+ translate([0, -armendwallthick, -armendbasethick])
+ cube([ratchetstep+overlap, totalwidth, totalheight]);
+ translate([-1, 0, 0])
+ cube([ratchetstep+overlap+2, channelwidth, channeldepth+1]);
+ }
+}
+
+ArmEnd();