Mountain Machine Works    Call 1-800-660-6680 Dial 0 How To Buy How To Use How To Finish Turn The ONLY Customizable Machinable  Expanding Mandrel

No more press fitting  

No more slippage   

No more limitations


Using principals of classic mechanics the Xpandrel body is deformed to conform to the internal features of your work piece.  This allows you to exert equally distributed forces inside your work piece regardless of features. Thus providing unparalleled holding power without damaging or deforming your work piece.



Functional, Versatile, Completely Customizable...

We’re Redefining The Mandrel.


We offer a variety of standard sizes and models but it doesn’t stop there. With the inherently versatile design of the Xpandrel countless variations can be created to meet your specific work holding needs.

Deflection, Elastic Deformation & Classic Mechanical Principals

The Xpandrel uses the fundamentals of Hooke’s law to deform the body of mandrel within its elastic limit and below the limit of proportionality of the material.  This elastic deformation allows you to repeatedly apply high holding forces without damaging or deforming your parts in the process.  Working within these limits reduces the possibility of material fatigue allowing you to repeat the process in a production setting without failure.  


How it is done

Using various methods of expansion, the Xpandrel body is loaded; then finish turned to the nominal limits of your work piece, and then relaxed.  The Xpandrel is now slightly undersized and ready to be loaded with your work piece.The deformation profile on the Xpandrel can now distribute radial forces evenly to your work piece throughout the working length of the Xpandrel.


Give us a call to discuss your current or future projects we can design an Xpandrel to optimize your outcomes.