Legacy Lowrance-Eagle Fish Finder Ball Mount

This is a 1" ball mount for a vintage Lowrance or Eagle fish finder. This will allow you to mount your fish finder using a R@M B size clamp. This replaces the rather stiff base bracket supplied with the unit and although you could just bolt a 1" ball to the bottom of the stock bracket, this solution is more compact and lighter. This will work with a variety of Lowrance units, including the X-4, X-4 pro, X50 DS, X67c, Eagle Cuda 300, 242, Eagle Fisheasy 320c, 350c as well as others. Despite being out of production for nearly a decade these units are still highly sought after by an elite group of canoe and kayak fisher people who want a basic fish finder with low power consumption.

This mount consists of 5 3D printed parts plus a 1/4" by 2 1/2" Hex bolt and a matching 1/4" nylon lock nut. There are two keyed pegs that are able to slide freely inside the circular housing. Each peg has 7 teeth that once in place lock into the corresponding recessed spaces of the unit. Once the pegs are fully inserted into the housing, you should have just enough space to slide the three pieces into the back of the unit aligning the pegs with the holes on each side. A wedge containing the lock nut is pressed by hand into place, driving the pegs home and locking in the teeth into position. Finally the ball which houses the hex bolt is screwed into the lock nut of the wedge, locking everything together. I like to use the R@M clamp to aid in screwing the Ball into place.

I recommend using the commercial R@M clamp versus printing your own as the printed ball does not have a rubber coating, so you will need to torque the clamp a little tighter to get it to stay. This is not a problem with an aluminum clamp, but one printed from PLA might break.

Note: I have printed each piece in a different color for illustrative purposes only. I find the dark grey color more pleasing and matches the x-4 unit well, so I it is the color I would choose to print all the parts for better aesthetics.

Tree supports are your friend here. I am using the Cura x-mas beta which has enhanced tree supports. Be sure to clean up your prints of any stringing or blobs that may prevent the parts from moving freely.