This is a work in progress - but I've built a dynamic valley rafter. Download the file here:

www.mikebeganyi.com/webimages/timber/ValleyRafterBeta.skp


This is for reg pitch / reg plan - so it assumes a plan angle of 45 degrees. I'll tackle irreg roofs when I have more time... and can shake the trig out of my brain.


Using SU7, right click on the rafter, call up the dynamic components options (all the way at the bottom).

Enter the beam height and width.
Enter the Main Roof Pitch.
Enter the common rafter run of the secondary roof. (1/2 the total width of what would be the gable)

The dynamic component will calculate the valley pitch, backing angle, and guides for the plumb cut @ the peak. I've added the data to the options box so you can read it out for shop drawings / joinery.

After the valley rafter is positioned (rotate 45 deg) - edit the VBeam subcomponent to cut the backing angle. Using the pencil, draw a few lines on the foot end tracing the backing guides. Use push pull to push it through to the peak. Use the guides at the peak to trace around subcomponent VBeam to adjust the plumb cuts (or grab the ends of the various planes and drag them until they snap into place).

You can toggle the guides on and off with the layer 'TimberGuide'.

I'll make a video of this when I have some time...



-Mike

I've updated a hip version. Been mighty sick so I haven't had time to do a YouTube...

www.mikebeganyi.com/webimages/timber/HipRafterBeta.skp

I'm still working out the peak detailing. Might add vertical guide lines. for a miter cut - but a hip tends to vary a bit more in its connections (in my experience) than a valley - so I'll have to think on this.

-Mike