Good morning DBS.
I agree with you that a canister will be better to reduce freezing the gas tank.
It has a larger exchange surface between liquid & gas : vapor pressure .
And the large surface of the envelope allows a better heat exchange between in & out !.
Now ! I am not sure that your N°5 jet (60 g/hr) is enough to supply enough heat to this boiler. Two Sun engines need a tremendous lot of steam They have to run fast and have no torque >> need a small pitch & size on the propellers , thus consuming a hell of steam.
Setting a larger jet size will improve the flame but will help cooling down and lower gas pressure faster , with the consequences you know.
It will not enlarge the boiler heating surface anyway.
i am very interested in you project and I shall take profit of it. Thanks for sharing.
Sunny days are coming , I am eager to see your boat in the water !
[size=0px]only for it to stop close enough to be reached with a fishing rod[/size][/u]
And then you realize that there is no beer left in the cool box !! ;-))