Positionning on a lathe:
<ul><li>top: hard chucks, creation of reference surfaces (red);</li>
<li>middle: machined chucks, creation the reference surface and of the bored hole (blue);</li>
<li>bottom: special device on the faceplate, final machining of the outside surface (green).</li></ul><p>For each situation, the views are:
</p>
<ul><li>left: front view;</li>
<li>middle: left view;</li>
<li>right: operations performed.</li></ul>
<a href="//commons.wikimedia.org/wiki/User:Cdang" title="User:Cdang">Cdang</a>
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<span class="int-own-work" lang="en">Own work</span>