Mini CW Paddle From Hard Drive Actuator

I enjoy making paddles out of weird and found materials and over the years have made many variations. Recently I decided to useparts from old hard drives as the basis for single-lever paddles. I made several variations using the motor’s bearing and the disc. They work surprisingly well.

However, the swiper (technically, the “actuator arm”) also has a very nice bearing and can be made into a useable portable paddle for QRP.

The easiest swipers to use for a paddle are entirely made of aluminum because the arms that hold the coil can be used as contact points. (In some, the arms holding the copper coil are plastic.) It may be that the metal ones come from older hard drive designs, though I am not sure of this.

I bolted the swiper to a 3 x 2 ¼” plastic box with a ground lug under the nut inside the box. This served as the central or ground connection.

Centering and tension are provided by a magnet. I used a banana plug terminal as an adjustable mount by inserting a flat-head screw through the hole in the center post and positioning a small magnet on the head of the screw. The magnet will stay in place by itself but after testing I glued it in place so that it couldn’t be knocked out of position. I glued it a bit off-center so that by rotating it, I could fine-tune the position of the magnet, thus affecting the centering of the paddle.

An alternative is to cut the magnet off a pickup tool, available from hardware stores, as I did in paddle at the top of this blog (detail below). This tool has a magnet mounted on a shaft, so one can simply snip off the shaft, leaving enough shaft to go through the terminal post.

The swiper needed some iron to attract the magnet, so I glued and wired a piece of metal across the coil. A nail with a flat head toward the magnet would also probably work.

Two small terminal posts are mounted on each side of the arm. Small machine screws through the terminal post holes serve as adjustable contacts. Lugs on the bottom side of the box provide connection points for the dash and dot wires.

Guitar picks mounted with a small machine bolt provide finger pieces though they aren’t really needed. To provide some weight, I filled the bottom of the box with split fishing sinkers.

After making this one, I made one more try at a small portable paddle, this time using the motor from a hard drive as a bearing and a repaired finger piece from an old Vibroplex (see below). Initially I used a magnet for centering but eventually replaced it with metal spring from an old relay.

Both of these small paddles work well.