P/N 2045
If you have ever been around a tool room in a standard machine shop, you have probably come across index blocks for 5C collets. They can save a great deal of time when doing simple indexing, and I have used them a number of times. It seemed like a good idea to add them to our line, so I included a couple of features for Sherline users. Rather than design them in a "six and four" configuration, I chose "eight and six", which adds more choices without adding cost.
I designed the blocks to use all of our spindle accessories rather than a particular collet size. If a tool fits the spindle of your lathe or mill, it will fit the indexer. (A special drawbolt of the proper length is required so that WW collets can also be used. It is available as an option.) The way we manufactured the index blocks kept the flats accurately machined in relation to the centerline of the spindle mount, so they should yield quite accurate results.
When put in use, the index block is held in a mill vise. To index your part, all you have to do after performing your operation is loosen the vise jaws, index the block to the next appropriate set of flats, retighten the vise and repeat the operation. For example, a part could be turned on the lathe in a 3-jaw chuck. The chuck could then be removed and screwed onto the threads on the end of the indexer. Then a hole pattern of 2, 3, 4, 6 or 8 holes could be drilled and tapped in the part using the indexer. In this case, the vise would be mounted on the side. (See Figure 1.) Likewise, flats could be machined to produce a special hex bolt with the vise clamped flat to the table.
FIGURE 1-A part turned in a chuck on the lathe is transferred to an index block and held in a mill vise while a 6-hole pattern is drilled. The vise could also be clamped flat to the table for milling flats or drilling holes on the side of the part. The vise is shown being held in position on its side with blocks from two P/N 3013 step block sets. There are also many other ways to use these handy indexing blocks.
To use tools or holders in the Morse taper, you will need to use shorter-than-normal drawbolts. For mill collets that use a 5/16-24 drawbolt, a 1-5/8" length bolt will be needed. For 1/4-20 drawbolts for items like the Morse #1 blank or drill chuck, a 2-1/4" length is needed. The special washers that come with these accessories can be used. If you don't have one, they may be ordered as P/N 30842 for the 5/16" drawbolt washer and P/N 30882 for the 1/4" drawbolt washer. There will soon be an adapter and drawbar available to use WW collets in the index blocks as well.
FIGURE 2-Short drawbolts and washers that can be purchased separately and used with index block set.
FIGURE 3-A special drawbolt for WW collets is also being produced. Ask for P/N 11681.
This indexing set is one of those accessories that you will keep finding more uses for the longer you have it around. It can be a real timesaver.
Joe Martin, President and Owner
Sherline Products Inc.
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