A couple of years ago I built a mount to raise my bow depthfinder so it was easier to see (I'm getting old) spider rigging. I used Ram C sized components, 1.5", it was fine until I went to a HDS 8. The height and weight was too much it to hold on rough water so I've been trying to figure out what I could build that would work.

The old.
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The new one uses a D size, 2.25" base and clamp with a 1.5" clamp and the mount I had on top. It's very sturdy now.
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