Here is a cool footnote to my post on the changing applications of shrink fit toolholding in machining. One of the applications for shrink fit toolholding at Advance CNC Machining is long-reach cutting. That is, the cases in which the complexity of the part design requires a drill or milling tool to be extended into some deep pocket, recess or valley of the part that is difficult to reach because of obstructing walls or features. Shrink fit does not have to surround the tool with a collet in order to clamp; therefore, it allows for slender-profile toolholding that can solve some of these accessibility challenges.
Here is an extreme case. The part Advance CNC machines with this tool involves one machined feature located deep within the part’s complexity. The reach needed is so long, the team lacks a shrink fit holder providing the needed extension. The solution therefore employs shrink fit within shrink fit within shrink fit: three different shrink fit holders from Lyndex Nikken.
The rigidity of shrink fit is such that even this setup allows for precise machining. Advance CNC says this progressive toolholder extension allows for 25-micron positional accuracy of the cut. With the cutting tool, the total length is 490 mm. The tool magazine of the Makino machining center using this tool setup accomodates tool lengths up to 510 mm, a capacity limit the Advance CNC team previously had no need to look up or confirm.