Long, slight tapers may be produced on shafts and external parts between centers. Internal tapers cannot be made by this method. Power feed is used, so good finishes are obtainable. Because most lathes are equipped with taper attachments, the offset tailstock method is seldom used
now. Its greatest advantage is that longer tapers can be made by this method than by any other. The taper per foot or taper per inch must be known so that the amount of offset for the tailstock can be calculated.Because tapers are of different lengths, they will not be the same tpi or tpf for the same offset (Figure I-351). When the taper per inch is known, the offset calculation is as follows:
Table I-8 Tapers and Corresponding Angles
When you set up for turning a taper between centers, remember that the contact area between the center and the center hole is limited (Figure I-353). Frequent lubrication of the centers may be necessary.
A more precise measurement is possible with a dial indicator, as shown in Figure I-357. The indicator is set on the tailstock spindle while the centers are still aligned. A slight loading of the indicator is advised, since the first .010 or .020 in. of indicator movement may be inaccurate, or the mechanism may be loose owing to wear, causing fluctuating readings. Set the bezel at zero, and move the tailstock toward you Figure I-358 Adjusting the threading tool for cutting tapered threads using the offset tailstock method. The tool is set square to the centerline of the work rather than the taper.
the calculated amount. Clamp the tailstock to the way. If the indicator reading changes, loosen the clamp and readjust. When tapered threads such as pipe threads are being cut, the tool should be square with the centerline of the workpiece, not the taper (Figure I-358). When you have finished making tapers by the offset tailstock method, realign the centers to .001 in. or less in 12 in. When more than one part must be turned by this method, all parts must have identical lengths and center hole depths if the tapers are to be the same.
Incoming search terms:
- taper turning by tailstock offset method
- tailstock offset formula
- tailstock offset method
- taper turning by tailstock offset method pdf
- describe taper turning by offsetting of tailstock method
- advantage of tail stok off set method
- formula of taibstock
- FORMULA OF TAPER TURNING
- Tailstock set over method formula