How identify a tangent point?

fred_wild

I want to draw a line perpendicular to a tangent at the point it hits the apex of a spline.  Can Onshape identify the point of tangency and place a point there?  Thank you.

NeilCooke

Sketch or 3D spline? What is your plane of reference?

fred_wild

In a sketch on the front plane.  Thank you.

NeilCooke

You could try drawing a vertical line down to roughly where the apex is, then add a normal contraint between the spline and the line. It might move the spline, but it will give you the apex point.

luke_labrie_cleary

Or, even simpler, just make a point, and make it coincident with the two curves you want to be tangent to each other. Then just click the point to get its location.

olivia_scott146

One thing I do is use a construction line with a Horizontal/Vertical constraint and then make it Tangent to the spline. That gives you the apex point immediately without moving your spline geometry around too much.

martin_kopplow

Easy: Leave the spline in it's own sketch, els i'll move. Make a new sketch on the same sketch plane. There, make a point on the spline somewhere, and draw a mid point line on that point. Make the line tangent with the spline. Then constrain the line to horizontal. That'll be the spline apex point. I sometimes use that with airfols and mold making. The trick is, that the line in the second sketch will not move your spline.

(Sorry for the late answer, this message got stuck until now)