WHATto build

[Guest sol]

i am going to build a telescope,as i live very close to the sea the telescope would mostly be used for water viewing,even though a spotting scope would be all i would need i am very keen to build a refractor out of brass tube being a retired plumber i have all the tools and knowlege to work with brass. having never built a telescope the only ideas i have come from the web .i was thinking under the lines of a 83mm achromatic

objective lense with a 900mm focus with a 1.25" *40 kellner eyepiece

does this sound like a good idea ??? any advice from you people who would know would be more than welcome. thanks in advance sol