This frame is all plain guage 4130.

Frame weight is not too high. The steel front end is about 3/4lb heavier than the Prophet it replaced. Overall it certainly isn't heavy. Using quality butted tubing would proably get it very similar to the Prophet, which being a Cannondale is a pretty light frame. But I never weighed the plain frame before I built it up.

My latest frame is 6lb including shock and BB (including steel axle). So steel bikes can be built up pretty light as long as you keep the desing simple.

Gert yourself on a frame building course. It teaches you a lot and gives you the confidence to have a go yourself.

 This looks sweet dude, isit all the same geometry as the prophet? Fancy building me one Id love the prophet with a slightly steeper seat tube angle that would make it pefect!

 This looks great. What tubes did you use? Butted, straight gauge? What is the weight of the frame? I am in the process of learning to braze to build something very similar.

 this is very cool