HELP-Rattle Cad BB to ST junction

I am trying to add a curved seat tube but the curve moves the ST off the BB and I cannot figure out what moves it back. Changing STA only moves the upper portion of the ST. What am I doing wrong?

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I have no experience with Rattle Cad but looking at the parameters, you have offset set to 0 which means the top of the seat tube is going to be inline with the center of the bb shell. To move the tube below the bend forward your seat tube offset needs to be adjusted.


That is what I thought but it seems that number is the extra tube to be mitered off(?) and maybe the left and right offset to the BB. I found the offset as a dimension in the drawing and was able to fix it.

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Glad you figured it out.

Out of curiosity, what wheel size is this frame being designed for?

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I think this was 29x2.8. Really just trying to figure out the program for now. I went ahead and did the paid version now that I have figured out what the program is capable of. It seems to have good capabilities for the price.

BFS has a really cool custom bent 35mm-31.6 post ST I want to build with.

I have been building in Free BikeCAD then transferring to paper drawings. I am hoping to move away from the paper drawings