Note to the Fusion 360 designers on the forum. I’m somewhat disappointed that Fusion 360 did not have “blood splattered steel” in the material list. It would have made the rendering so much better!
It is not one continuous piece (like the sword I made). Instead, I made the blade as long as possible, while still fitting within a 20" bed. To make it feel more solid, it sits within a cavity in the handle part. If you look at a cross-section, it looks like this:
The blade part the protrudes the handle part is about 16" long. You can find real chainsaws with that size blade, although they are “light duty” chainsaws.
If you have pro, you could lengthen the blade parts and make a longer blade using the passthrough slot.