Sine bar is an instrument which is used for measuring smaller taper angles. Here taper means slant(inclined). So, the smaller angles are determined accurately by using Sine bar.
While using a Sine bar for finding the taper angles, some other intermediate equipment are required. Those are Surface plate, Slip gauges and a Dial indicator. By using all these tools a proper arrangement is made to find the taper angle value.
Methodology:
First we should clean the surface plate by using oil or grease to remove dust particles on the plate. Now, take the Sine bare and clean it too and place it on the surface plate. The cleaning of the tools is very important to confirm the accuracy in the measurement. Take the tapered object whose angle is to be measured and place it on the sine bar. Now, take the dial indicator and place it on the surface plate. Arrange the plunger of the dial indicator on the taper object where the smallest height of the taper surface takes place. While arranging the plunger at this end, apply some initial pressure to the plunger. After that make the indicator on the dial pad to coincide with zero by rotating the bezel of the dial indicator. When you rotate the bezel, the dial pad also rotates. Now move the indicator on the taper object from initial end to final end and observe the reading on the dial indicator. This reading gives you the height of the slant of the tapered surface. What ever the value we get on the dial indicator according to that we need to select the number of slip gauges to that value. The thickness of the slip guage would be given its surface. By observing its thickness select the slip guages by joining which we get the same value as we observed on the dial indicator.
Now, take those slip gauges and arrange them below one of the rollers of the sine bar where the smallest height of the taper object is taking place. When you do this the taper surface of the object becomes parallel to the surface plat. To confirm the accuracy of the parallelism once again move the dial indicator over the tapered surface. If any fluctuations are there in dial indicator in clockwise or anti clockwise, we should add or remove the gauges for confirming the parallelism of the taper surface with the surface. Once there is no fluctuation the dial indicator while moving over the taper surface from one end to another end, then we can confirm the parallalism. The total arrangement is given in the figure below provided.
Now, we need to apply the sine rule by constructing a right angle triangle with the help of height of the slip gauges and distance between the rollers of the sine bar as shown in figure below. Then we can find the what is the theta value which is only the required value.
The distance between the rollers is in between a range of 100 mm to 150 mm.
While using a Sine bar for finding the taper angles, some other intermediate equipment are required. Those are Surface plate, Slip gauges and a Dial indicator. By using all these tools a proper arrangement is made to find the taper angle value.
Methodology:
First we should clean the surface plate by using oil or grease to remove dust particles on the plate. Now, take the Sine bare and clean it too and place it on the surface plate. The cleaning of the tools is very important to confirm the accuracy in the measurement. Take the tapered object whose angle is to be measured and place it on the sine bar. Now, take the dial indicator and place it on the surface plate. Arrange the plunger of the dial indicator on the taper object where the smallest height of the taper surface takes place. While arranging the plunger at this end, apply some initial pressure to the plunger. After that make the indicator on the dial pad to coincide with zero by rotating the bezel of the dial indicator. When you rotate the bezel, the dial pad also rotates. Now move the indicator on the taper object from initial end to final end and observe the reading on the dial indicator. This reading gives you the height of the slant of the tapered surface. What ever the value we get on the dial indicator according to that we need to select the number of slip gauges to that value. The thickness of the slip guage would be given its surface. By observing its thickness select the slip guages by joining which we get the same value as we observed on the dial indicator.
Dial Indicator
Slip gauges box
Now, take those slip gauges and arrange them below one of the rollers of the sine bar where the smallest height of the taper object is taking place. When you do this the taper surface of the object becomes parallel to the surface plat. To confirm the accuracy of the parallelism once again move the dial indicator over the tapered surface. If any fluctuations are there in dial indicator in clockwise or anti clockwise, we should add or remove the gauges for confirming the parallelism of the taper surface with the surface. Once there is no fluctuation the dial indicator while moving over the taper surface from one end to another end, then we can confirm the parallalism. The total arrangement is given in the figure below provided.
Now, we need to apply the sine rule by constructing a right angle triangle with the help of height of the slip gauges and distance between the rollers of the sine bar as shown in figure below. Then we can find the what is the theta value which is only the required value.
