Norm

I am, and was guessing that you were going through the exercise of cutting this shed, not only to have a great little bldg, but to learn as much as could be realized in the doing…

So I’m going to elaborate on the quick sketch I threw at you before. You may have carried your project to the next phase, even so this aspect of framing can be understood just by playing with ideas.

Go back to the drawing I asked you to create earlier, step over to your problem plate, even if you have it completed. Snap those datums - datums being the lines which describe those two perfectly perpendicular planes of reference which flow through your imperfect timber. And any and every timber for that matter. If you haven’t done this before, e me and I can walk you through the process. For purposes of this exercise simply draw a parallel line 1 ½ “ from the two reference faces > top & outside < of your theoretically perfect 8 X 8.

Now go to your stick, walk a third of the way down, to one of your rafter locales – approaching the apex of your crown but not to the half way point, where wind cancels it ‘self out.- Physically measure the actual distance from the datum to the imperfect surface at all 8 locations – 2 for each of the 4 sides – bring this information to your drawing and connect the dots, You now have a completely accurate representation of the imperfections your timber holds at this location.

For most joinery all you need to do is treat your datum as an 1 ½” offset to draw then create your joint in it’s perfect plane – a ½ “or 1” from theoretical reference or whatever the need demands. Joints which approach their surface a an angle are another matter !

Back to the drawing and the step laps, extend the lines up through the lines you drew which describes the actual surfaces, now measure the distance from the datum and convey this information back to the stick, and so on and so forth.

Like I said youcan know the actual points at which the joints enter and exit the true surface. Yes you can, describe and then cut perfect joinery into any timber no matter how imperfect.

If there is a catch, it is that you must reference the tooling that you use to create these “perfect” joints from those perfect planes ie; you must create a plane parallel to it from which to register your combo/protracter/bevel/what have you.

Best of luck
and
Be your best

Will