I got this

radial.axis = -v.vector(5*cos(phi)*s[1]**2, 5*sin(phi)*s[1]**2) # -m*r*omega^2

transverse.axis = v.vector(5*sin(phi)*alpha, -5*cos(phi)*alpha)/(2.1*g) # m*R*alpha

I'm not sure this is correct though, what's happened to m*g being subtracted?

Is that needed?

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I know where i was going wrong with the angles now, I forgot that they're measured from the line x=0 to the pendulum bob's position :P