Morse Code Mini Cootie Key (Sideswiper)

prusaprinters

<p>This is my take on a compact Morse Code sideswiper key, (also called cootie keys.) Unlike the traditional telegraph key which uses an up-and-down motion, the sideswiper makes contact on either side of a flexible arm, making for much less hand and wrist fatigue.</p><p>This key uses a short length of hacksaw blade as the lever arm; this is a ham radio tradition for these kind of keys, which were often home-brewed out of inexpensive materials on hand. Alternatively, you can use a strip from a feeler gauge. This approach allows selecting the flexibility of the lever by which thickness you choose.</p><p><strong>What you will need</strong><br>A piece of hacksaw blade about 85mm long OR a steel strip from a feeler gauge.<br>Brass or stainless steel #8 hardware for assembly.<br>Brass or stainless steel #4 hardware to attach the finger pieces<br>about 2 feet of 20 or 22 ga solid wire</p><p><strong>Preparing the hacksaw blade&nbsp;</strong><br>Cut or break the blade to length (wear goggles!).<br>Sand off the paint on the blade. If you don't want to do the whole blade, make sure the portions where the supports and contacts are clean of paint.<br>You can use ScotchBrite to shine up the surface a bit after the paint is removed.<br>Finish the cut end with a file to remove sharp edges and burrs. (wear goggles!)</p><p><strong>Preparing a feeler gauge strip.</strong><br>Typically you can use the existing hole in the strip for one of the lever mounts.&nbsp;<br>You can use ScotchBrite to shine up the surface a bit.</p><p><strong>Drilling the Lever</strong><br>Measure 8mm from the left end of the lever, and drill an 11/64th hole (5mm) centered on the blade. Go slow, the steel blade is hard. Wear goggles!<br>Add a second centered hole 12mm to the right of the first. These holes are for the lever mounting.<br>Flip the lever end-to-end, &nbsp;drill a 3mm hole 11mm from the left end, for the mounting screw.&nbsp;</p><p><strong>Preparing the connecting wires.</strong><br>Break the shanks off of three #8 ring tongue terminals.&nbsp;<br>Strip the insulation off one piece of 20 - 22 ga wire, this is the wire that will be used to connect to the lever.<br>Solder the bare wire to one ring tongue, and two lengths of insulated 20 - 22 ga wire to the other two. See the photo.</p><p><strong>Assemble the pieces</strong><br>Poke the bare wire into the hole between the support pillars, slide the lever in as well, and use an awl to line up the holes.&nbsp;<br>Use the bolt, washers, and nut to secure the lever in both holes, and tighten securely.<br>Drop a wire with a ring tongue on it through each of the wire holes, on the base just inside the contact pillars.<br>Thread a nut all the way onto each of the contact bolts, and add a flat washer. Push the assembly through the contact holes and place the ring tongue over it on the inside of the pillar. Add a nut to secure the assembly. You can change the contact spacing by adjusting the nuts to give the right spacing when both nuts are tightened.<br>Attach the finger pieces to the end of the blade with the #4 screw, washers and nut.</p>