Civil Engineering Reference
In-Depth Information
Fig. 2.8. The R8 taper is more likely to be found on the larger milling machines such
as a VMC or Bridgeport turret milling machine. It is seen here on a flycutter.
Whichever collet system you get, you must use a drawbar through the
spindle. The collet must be held firmly and the cutter should be tight. Plain
split collets are available in both 2 and 3 Morse tapers, but a better bet is to
get an ER collet holder and a set of collets. These collets will close down in
size, many by 1mm and the rest in
1
⁄
2
mm steps. These will hold cutters very
firmly and are the way to go. You do not need the entire set of collets at the
start, just the ones that hold the standard shank cutters such as 6, 8, 10 and
12mm or their imperial equivalents.
There are various ranges available in the sizes we are likely to use: the
ER32 range which takes up to a 20mm collet, the ER 25 range that takes up
to 16mm collets, the ER 20 range which takes up to 13mm collets and the ER
16 range which takes up to 10 mm collets. I suggest you get the ER 20 range
or the ER 16 range with a matching holder suitable for your lathe. The match-
ing holder can be clamped down to the milling machine's table or to an angle
plate to hold work to the milling machine. You can also add a 16mm side-lock
holder to take the larger 16mm shank cutters and a 12mm side-lock holder if
