Final answer:
The bevel in a scarfed joint must be accurate to ensure perfect alignment, a larger adhesive bonding area, and a stronger joint that can withstand tension and compression forces, while also providing a smooth appearance.
Step-by-step explanation:
The accuracy of the bevel in a scarfed joint is crucial because it ensures that the two pieces of wood will align perfectly. A scarf joint is used to join two pieces of wood end to end, where each end is cut in a complementary angle so that they fit together seamlessly. An accurate bevel allows for a larger surface area, which provides more space for adhesive bonding. This results in a stronger joint that is better able to resist tension and compression forces. The smooth transition between the pieces also ensures a better appearance, which is important in fine woodwork where the joints may be visible.