Adjust the saw for a 35 degree cut, and clamp the pipe into place in the saw. The cut will not be at the center of the pipe; it will be offset from center about quarter inch.
Put a C-clamp on the pipe to act as a stop which will guide you in making the same length of a cut on the opposite side. Make the first cut at a 35 degree angle.
Remove the pipe from the saw clamp and turn it 180 degrees, using the C-clamp as a guide to know where to stop turning. Make the second cut opposite the first. This will leave a small flat spot between the cuts rather than a point.
Place the pipes together, grinding as needed to adjust them.