Hi
I must say this first, TBN forums are GREAT! It does not matter what you post there is always a response from a broad spectrum of people, unlike so many other forums.
<font color="blue"> What are gas tanks usually made of? </font>
I have seen stainless steel, aluminum and mild steel but unfortunately I have not been able to take to anyone that has mild steel tanks.
<font color="blue"> Do you have regulations that appy to building boats </font>
There are no regulations that apply to building houseboats here in oz with the exception of navigation and safety gear, and EPA requirements regarding black water, unless you hire them out.
<font color="blue"> Most tanks I've seen on boats are aluminum. Stainless would be nice, but too expensive. </font>
Mild steel would be much cheaper for two reasons; one the price of materials and two I can do the work myself.
<font color="blue"> My Dad and I had a boat that we built mild steel custom gasoline tanks for. We owned that boat about 15 years, using it in fresh and salt water and never had a problem </font>
David do you remember what thickness steel was used and how big where they