I was wondering what your approach would be to this problem. I have a few work arounds but my gut feeling saiz there are better solutions.
So I have a corner which I would like to fillet, but the top of the fillet should still make contact to another curve as the original corner did. The tricky thing is that the two lines that form the corner have to start from a rounded curve (continuity).
My current approach drawing the corner a bit beyond the contact line, and then do the fillet but I don’t know how to control the fillet so it rounds nicely against the contact line.
First, some geometry. To have a fillet the two side lines can not meet at the base line as in your example on the left if the fillet is also tangent to the base line. The distance between the intersections of the side lines and the base line needs to be greater than zero to have a fillet with a radius greater than zero. This also means the side curves if extended will intersect on the other side of the base line.
Procedure for creating a fillet tangent to the side lines and base line given the side lines and base line:
Draw a temporary line with bisects one side line and the base line. Use Line with the Bisector option with Int OSnap at the intersection of the side line and base line for the start of the line.
Draw a temporary line with bisects the other side line and the base line. Use Line with the Bisector option.
The center of the fillet arc will be at the intersection of the two bisector curves. Draw the arc using Arc with the Int OSnap at the intersection of the bisector curves for the center, the Perp OSnap on one side curve for the start of the arc, and the Perp OSnap to the other side curve for the end of the arc.
Trim the side curves with the arc and Join if desired.
It’s all in how you define your requirements. There’s absolutely no question that if you must have a “fillet” at the point, whatever straight lines you have coming in from the sides must be tangent to a circle of fillet radius which is also tangent to your baseline. So start by drawing this circle with it’s center 1 fillet radius from the baseline.
Use tangent Osnap to place the ends of your straight lines, then trim off the unused part of the circle using the straight lines as the cutters.
Of course, if the straight lines must exist exactly as they are shown, then putting a fillet on them which is tangent to the baseline is, as David pointed out, impossible.
Stumbled upon a new problem, I tried your bisector technique, very cool… just now I want to make the fillet connection between 2 rounded curves. The bisector approach doesn’t do it here, any other suggestion?
Does the fillet have to be a circular arc? If so I don’t know of any simple method t find an arc which is tangent to a straight line at a point and is also tangent to a curve.
If the fillet needs to be an arc and tangent to the end of the curve then in most cases there will not be an arc which is tangent to a straight line at a point and also tangent to the end of the curve.
If the fillet can a blend curve then use Blend or BlendCrv between the end of the curve and a straight line on the base line which ends where the fillet is to be tangent to the baseline. distance_fillet_2 DC.3dm (29.7 KB)
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