Ferrule Installation

Click on the thumbnails for more details. The ferrule installed here is Mason's Micarta Tube with a 3/8-24 thread.  This is only one method of installing a ferrule but it incorporates some of the best ideas.  A register diameter is nice for accurately locating the ferrule concentric to the tenon while the threads provide a solid mechanical bond.  The cross section view shows how nicely everything fits.  The fine threads fill the tapped hole almost perfectly for a solid connection.  I recommend the use of a 1/4" shank cutting tool to reduce cutter deflection.  It definitely won't look like this if you use a compression die.  

See HERE for one method of threading a tenon. Note that the video shows 3/8-16 threads being cut while the above pictures show 3/8-24 threads. I've experimented with 5/16 tenons in 18 and 24 pitch and also 3/8 tenons with 10, 16 & 24 pitch.  All things considered, I prefer 24 pitch.**  The tenon remaining is about as strong as you can get while still using a ferrule.  It is significantly stronger than a 5/16 diameter tenon with the added benefit that it is not excessively undercut by a coarse thread.

**UPDATE ON THE PARAGRAPH ABOVE:  After experimenting with 3/8 threads for quite some time, I'm revising my statement about preferring 24 pitch.  That pitch seems to be a better solution with MM or LBM - mainly because it's easier to cut the smaller threads in the ferrules.  However, when using Juma, Elforyn or Ivorine 3, I find that I like 3/8-16 instead.  When using ivory, I go "old school" and use a 5/16-18  capped ferrule with a .250" long shoulder.


Another sequence showing the installation of a short ferrule on a 3/8-24 tenon.  This tenon also has an 1/8" locating register at the shoulder.


This customer wanted 3 shafts with 3/4" long capped black linen ferrules.


Ivory Ferrule Construction & Installation in 2 Pictures

Progression of an ivory square as it becomes a ferrule.

Progression of the ferrule installation on a 5/16-18 tenon.


Ferrule installation video using all live tooling.

Page 4 - Micarta and its Relatives

Page 5 - Ferrule Weight