Revolved surface

[Rakesh]

Hi everybody

If someone can explain how to decide the direction of angle in creating the revolved surface. For example, If we have a curve as a profile and a line as a axis, I want to create semi cirle surface,means surface on the top half than how we decide the start angle gonna be 0 or180 and end angle will be 180 or 360. So far I always get the result by flipping option.

Thanks in advance.

[RobertELee]

The default direction should be counterclockwise. Lets say you have a line at 3o'clock and you want the surfaces to stretch between 3 and 2o'clock you would type in 0deg in the first box and 30deg in the second. If you wanted a surface between 3 and 4 you would type in 330 deg in the first and 0 in the second box.

 

But remember, the degrees is always going to be from the entity, so if you have a line at 9o'clock and you want a surface from 9 to 8 you would type in 0 and 30 in the respective boxes.

 

HTH

[FP1]

When revolving a surface the default direction is not always counter clockwise for a positive rotation. The positive direction depends which end of the axis you pick.

 

When you pick the axis you will see a circle with an arrow. The arrow start point is 0 degrees and the arrow pointer is telling you which way is a positive rotation.

[RobertELee]

I guess your right FP1, I had never noticed that. I must have always selected the correct side of the axis. OR just hit the inverse button Thanks, now your going to make me overthink it next time I have to revolve a surface!

[FP1]

It drove me crazy for a long time.

I tried it many times and then finally one day.........

[Rakesh]

Hi everybody

In the bellow surface,start angle box shows the 0 deg and finish angle box shows the 180 deg.

Now if I see, drive profile should be the start angle and if we see the arrow concept it should have the value of 180 deg and since the surface is at the bottom half, the end angle should be 360deg. If I give these values as Start angle 180 and Finish angle 360 the surface created at top. I don't want to use the inverse option to get my result right. Does the inverse button already prssed in the image I am showing?

If someone can clear this concept

Thanks in advance

[FP1]

I see your point. Let me re-phrase that. The arrow pointer is still telling you which way is a positive rotation. The zero degree starting point is the chain that was picked to revolve.

 

(edited) In my earlier post I assumed the chain was drawn above the X-axis and the arrow was pointing in the opposite direction than yours. In your case the chain to be revolved was below the X-axis which is why 0 degrees start and 180 degrees end is correct in your drawing.

[Rakesh]

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The arrow pointer is still telling you which way is a positive rotation. The zero degree starting point is the chain that was picked to revolve.

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Yes FP1, this statement now satisfy all the cases of Revolve surfaces.

Thanks