get_old_spacing: Get the over-locknuts-dimension (OLD) spacing

In ghuiber/bicycle: Design a bicycle frame

Description

In the plane that is perpendicular onto the bike, the chain stay is part of a trapezoid that is as wide as half the OLD spacing at the dropout and half the bottom bracket shell center offset at the bottom bracket. The OLD spacing is standard (130 mm for road bikes, 135 mm for old-school mountain bikes, 142 mm for newer mountain bikes, etc.). So the OLD spacing is an input in frame design, not a derived dimension. This function is only useful as a sanity check, to make sure that you hit the right OLD number with a given set of values for its arguments.

Usage

get_old_spacing(cs_length, angle_btw_css, bbsc_offset)

Arguments

cs_length	Chain stay length in millimeters.
angle_btw_css	Angle between chain stays, in degrees.
bbsc_offset	The bottom bracket shell offset in millimeters.

Value

A scalar equal to the OLD spacing in millimeters.

Examples

get_old_spacing(450, 10, 10)

ghuiber/bicycle documentation built on Dec. 20, 2021, 10:46 a.m.