Spindle Tooling
In keeping with many manufacturers of the era, some Van Norman machines use a proprietary spindle taper. The No. 6, No. 12, and some of the No. 16 ram type mills use what Van Norman referred to as their "C" taper (Hardinge refers to this taper as 5V today). This taper was also used in some of Van Norman's smaller dividing heads and auxiliary milling subheads. Some of the larger machines use Van Norman's "No. 2" taper (Hardinge 50V), and some of the larger dividing heads and milling subheads use this taper as well. Larger machines used an assortment of tapers—earlier mills will most likely have either some size of Brown & Sharpe taper or Van Norman's "No. 2" taper. Later mills usually have NMTB milling machine tapers (30, 40, or 50, depending on machine size). It is probable that any machine could be ordered new with any taper the buyer desired.
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