Why is my spline curvature not the same? See attached.

Why is my spline curvature not the same? See attached.

I don't really know, I don't have much experience with splines. If you delete that 12.2 dimension you'll probably be able to drag them manually and get them about the same, then add the dimension back. But I don't know if there is a way to do an equal relation or something. Your best bet might be to just sketch half of the curve and fully dimension it and then mirror.

Once if you drawn Drag handles and made changes. just undo it. Then select spline. By pressing "ALT" drag the arrow of spline.

Thanks and Regards

Venkatesh S

Application Engineer

E G S Computers India Pvt. Ltd.

http://www.egsindia.com | http://www.egs.co.in | http://www.egsindia.blogspot.in

I think it's just that the dimension on a spline handle defines the total magnitude of both handles coming off the point, but it doesn't define the ratio of those handles. I think when you first draw the spline the handles would be symmetric, and then if you dimension it right away they will stay that way. But if you drag one or both handles so that they are no longer equal, then adding the dimension scales them and locks them but keeps the ratio the same. And as far as I can tell there is no way to make them equal again, apart from deleting the dimension and manually trying to drag them so they look the same.

A better method would be for SW to let you define the magnitude of each handle individually.

John,

We need to attract Mark Biasotti's attention to this thread. I swear that in the good (or bad, depending on your point of view) old days, we couldn't control the two sides of a midpoint tangency separately. I thought that when that capability was added that the system defaulted to changing the two sides equally but gave you a way to manipulate them independently. But that doesn't seem to be the way it works and I don't have a clue how to force the two sides to be equal.

Jerry S.

Or, delete 12.200 dimension, in 3rd point of spline uncheck maintain internal continuity and select manualy Tangent Weighting1 and 2. Then add 12.200 dimension and check/or no maintain internal continuity again. This is a spline

John, splines aren't plotted in a sketch the way lines and other curves are. With splines, you get different levels of complexity at each point. So, not only does a 6 point spline change more drastically than a 3 point spline, the fourth point changes more drastically than the 2nd point.

The "Reset Spline" and "Relax Spline" tools in the Property Managers, redistribute the stress in the spline by repositioning the handles and changing the order of the curvature so that the spline finds a solution that doesn't flake out as easily.

Even with these tools, there's no parameter you can set for a spline that will explicitly establish symmetry within the curve. Unless you need curve level continuity at the apex of your curve, you should put a center line in there, constrain the apex end of the spline tangent to to a vertical construction line and mirror the curve.

It looks like these two handles aren't the same length.