Thread: Size of tube for marine hardtop

Hey guys.
I need to make a hardtop arrangement for a boat. Wondering what size tube is best suited. I was thinking 40x3 round tube but I'm not sure if that's too heavy. If I could get away with say 1.6mm it would be a bit cheaper and lighter. The main bar also has to hold rod tubes so maybe I could use the heavy stuff for the main bar and lighter tube for the rest of the frame. Any ideas?

How long is a piece of string? ie: we need more info such as spans, loads, material etc.

Also if I use aluminum sheet as well, whats the go with dissimilar metals and galvanic corrosion etc? Do I need to install anodes?

Dissimilar metals do not do well together, especially in a saline environment.
Without knowing what material you intend to use for the tube work, I can't say much more, except to ask questions, so I'll start with one......
Is it a plastic, steel, aluminum or timber hull?

Fossil, I realised only how ambiguous my post was when I read over it. Yes indeed lots of info missing!

The boat is a 6m Haines so its glass, the top will span just over 2m. Length will be about 1.5m. Tube will be round 316 stainless. The top sheet will be ali checker plate. Like I said the main bar across the back will also have to hold several heavy rods and reels. The rest of the bar work will only have to hold the top and support the windows.

Cheers for any help.

Are you contemplating something like the photo