I wanted to turn a few Christmas present projects that exceeded the capacity of my Jet mini-lathe. Being frugal (cheap!) I wondered if I could build my own extension instead of buying a $100 plus factory cast iron model. I saw on the interweb a few other's had built their own so I decided to give it a try. Here is my versionI measured the cast iron surfaces on my lathe and found they were 1-1/2" wide x 5/8" deep. I used 1-1/2" angle iron to form the extension surfaces and added maple fillers below to bring the thickness up to 5/8" to match the lathe cast iron. The Maple has proven hard enough to hold the tail stock and tool rest clamps just fine. The wooden block on the attachment end is sized so that it's bottom rests on the machined "lip" on the end of the lathe. This keeps the angle iron surfaces in perfect alignment with the surface of the cast iron.To hold the wooden extension to the lathe I used threaded rod. Two 3/8" rods at the top provide tension and hold the extension tight to the lathe while resisting downward forces... I drilled new holes closer to the top of the lathe then the existing metric holes in the lathe to provide this tension support nearer the top where it's needed.Near the bottom I drilled and tapped a 5/16" hole for a single threaded rod which supports the bottom of the extension and pulls the extension down into two leveling "gibs". These gibs are 3/8" bolts in tapped holes and are adjusted in or out to raise or lower the end of the extension to align the upper surface parallel with the existing lathe.Once the threaded rods are adjusted and tensioned, the lathe extension proved solid and steady. It works great and the total cost was $10 or less for the threaded rod and angle iron scraps. The savings might go to a Lathe upgrade if I find myself turning longer items more often.