1″ X 8 Niles ™Mandrel
$24.98 with 2 stub drill bits: 5/16″ and 11/32″ $25.70 value
$28.98 with 2 stub drill bits and 3/8″ tap $30.95 value
This Niles ™mandrel threads onto the head stock spindle and has the unique tapered-cut flute making it the best self-tapping mandrel on the market. It has a 3/8″ x 16 tpi threaded stud that works with just about all the stoppers on the market and numerous other projects: ice cream scoop handles, shaving brushes, pizza cutters, etc. They have a black oxide coating for rust prevention. The neck or step below the threaded stud is 13/16″ diameter which matches the tops of all my stoppers. This mandrel does not use a draw bar. It comes with 2 nylon spacers (a spare because you will lose one!) which are used to help keep the wood from locking on the mandrel as you turn it.
*Tip: if the wood does get a death grip and you can’t get the project off the mandrel, put the whole thing in the freezer for 10 – 15 minutes and it will unthread once the metal shrinks. Also try a little beeswax or soap on the mandrel before threading it into the wood.
The shorter stub drill bits won’t “wander” if they hit a tight wood grain. The 5/16″ is the standard size when threading a 3/8″ hole; the 11/32″ is for dense wood, acrylic and resins.
The bottoming tap cuts threads all the way in unlike regular taps that leave about 1/4″ untapped and it makes threading quick and easy.
Check this page: Mandrel Comparison if you are not sure which mandrel to purchase: this page explains the differences and usages.
Basic bottle stopper turning video (threading the mandrel starts at about 3 min.): Roper Woodturning
Made in the USA (only in Missouri)