The Miller's Tale - Part 2

摘要

In my previous article, I mentioned my plan to make a vertical head for the Trident C horizontal mill based on the article by J.M. Wilson published in Model Engineer in 1984 (ref 1). His design has no vertical feed, but on reflection I can live without it by using the vertical movement of the knee, and so save myself a lot of extra work both in design and construction. In Part 1,'TheMiller's Tale', I mentioned that the bores for the horizontal spindle and the overarm needed to be rebored as they were somewhat out of line. The plan was to use the vertical head mounted on its backside, i.e., horizontally, on the milling machine table, and use it to bore out the offending holes. Drive for the head was taken from the lathe by moving the mill in front of the lathe and using a belt drive from a pulley mounted between centres. The advantage is that all the lathe spindle speeds are available to drive the boring head at the correct speed. The spindle for the vertical head was made about 8 inches longer than the finished length, and the extension used as the boring bar to bore out the holes mentioned above. This was later cut off and the spindle finished to length and bored out to take R8 collets and a draw bar, as per the original design by Mr Wilson.