Cut an angled edge

these chairs imo look good, unfortunately I am not nearly a designer of that level, I bought the design and made them.

However the marked edge make them almost impossible to lean at, what experienced carpenters see at the first view, a friend of mine did.

Now I am about to make the next generation with an angled backrest.

Therefore the pieces
back experimental.DXF (104.5 KB)


should have a cross section like a parallelogram (2), not a square (1):

The pieces are made from 1" plywood, glued to 2" thickness, Since plywood is so extraordinary expensive, always miserable quality (never AA) with holes in the middle and black pieces on the edges and this pattern leaves a lot of scrap I intend to make the next generation from solid boards.

However the question stays whether that pattern and that edge can be cut with a 30 deg vcarve bit. (edit: sorry, to get a 30deg edge a 60deg vcarve bit will be needed…)

Any ideas?

Is that 60 or 30 degrees?

If 30 degrees, cut along one edge with a 60 degree V endmill:

Then flip:

and cut the other edge:

30 deg to be cut off, 60 should stay. So the 60deg bit should be ok. The cutters usually just have fractions of 1" cutting depth, so in order to cut that edge in that depth: how to define the contour?
with a 60deg CC gives me


instead of

Solution?

Draw the cut up in profile and make several offset passes.

when you say it, it appears always so simple. Sure! That’s it! TY!