This is my old tool, square tubing and a carbide cutter on the end.  I've made dozens (over a hundred) pens with this, bowls, Christmas ornaments, and all sorts of little projects.  I made the new tool with this.

Look at that jacked up tip, it ain't even straight!

And here we go, a 25 inch weapon of mass wood destruction.  My wife asked me "what if it breaks?" I was like "baby if this thing breaks you'll learn some new cuss words because if it broke it means I just saw my life flash before my eyes".  Total cost was maybe, $12, maybe.

Rounded down the tip real good so the cutter has easy access to all that wood.

The handle is black walnut and cherry scraps.