Another newbie asking a boiler size question.

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Nov 10, 2018
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I am planning to build a V twin wobbler either a copy of the Stuart or slightly larger at 1/2 inch bore.

I am thinking of using it in a slipper launch style model boat 40 to 45 inches long.

I am going to run a camp stove pressurized heat source capable of boiling a litre of water in 5 minutes. [ Heat output is controllable ]

I have been trying to work out what size of boiler I need. This would be my first attempt at a boiler and I would stick to the 30 psi limit.

I have ordered a copy of Model Boilers and Boilermaking Paperback by K.N. Harris (Author), Edgar T. Westbury but will not get it until Lat Feb. {There are downsides to living on a boat and drifting around the Caribbean. }

I think a 3 inch vertical boiler with a simple internal 1 inch chimney should do. I will be running slow most of the time and runs will be limited to 10 minutes.

It would suit me to order the copper tube in Jan/Feb so I can pick it up when I visit the USA.

So question 1 Am I in the ballpark with a simple 3 inch vertical boiler. running at 30 psi.

Will I get 10 to 15 minutes running time before I need to pump more water into the boiler.

Question 3 are there different grades of copper tube. One site that supplies modellers quotes 150$ for 12 inches of 3 inch pipe. I can get the same amount [type L ] for 40 $ on Ebay. Will that do the job.