making an Arbor

This is for a 1849 Colt Pocket. in the 19th century this was Colt's best seller. Mine is an Italian clone from around 1960 not made by one of the surviving Makers (Pietta, Uberti, Armi San Marcos - that last one is also dead but died more recently) I really do not know who made it. The arbor is broken and this is me on my lathe cutting a steel bar to near the correct dimensions. I am not really a machinist, nor am I a videographer (obviously) but if interested, this was how that process begins.