berol Posted April 10, 2010 Share Posted April 10, 2010 Using Autocad 2000 LT and am trying to do a design of a part which has several curves. First I am trying to draw a curve from a point on the narrow side of a rectangle to a point on the wide side. This would be layed out on a piece of 1/4" metal plate and cut with a bandsaw. Tried using an arc, it starts out at the point on the narrow side but doesn't want swoothly end up at precisely the predetermined point on the wide side. If I get it to end precisely at the point on the wide side it does'nt make a smooth transition. When I zoom in on that point the arc appears to go outside the rectangle before comming back to the predetermined point. What am I possibly doing wrong or is there another way other than arc to draw this curve and have it make a smooth transition to the side ending at the precise point? Quote Link to comment Share on other sites More sharing options...
eldon Posted April 10, 2010 Share Posted April 10, 2010 I don't know what commands are available in 2000LT, but I presume that you have Polyline. Draw a straight polyline between your two points. Then go into Pedit, define the tangents at each end of the line (along the sides of the rectangle), and then use the option Fit. Or if you have the Spline command, you could arrive at the same thing. A circular arc only works when the distance from the corner is the same along each leg. Quote Link to comment Share on other sites More sharing options...
dshowalt Posted April 10, 2010 Share Posted April 10, 2010 I presume that the radius of the curve is something you know. Just draw a TanTanRadius circle and pick the two points on the rectangle as the tangent points, input the Radius and draw a circle. Now trim the part of the circle you don't need out. Quote Link to comment Share on other sites More sharing options...
Dana W Posted April 10, 2010 Share Posted April 10, 2010 Using Autocad 2000 LT and am trying to do a design of a part which has several curves. First I am trying to draw a curve from a point on the narrow side of a rectangle to a point on the wide side. This would be layed out on a piece of 1/4" metal plate and cut with a bandsaw. Tried using an arc, it starts out at the point on the narrow side but doesn't want swoothly end up at precisely the predetermined point on the wide side. If I get it to end precisely at the point on the wide side it does'nt make a smooth transition. When I zoom in on that point the arc appears to go outside the rectangle before comming back to the predetermined point. What am I possibly doing wrong or is there another way other than arc to draw this curve and have it make a smooth transition to the side ending at the precise point? Does 2000 have "Fillet"? Does 2000 work with a mouse? Are the points equidistant from the corner on each side? Is this curve to be an arc? In other words, is the curve to be 1/4 of a circle? If so, simply use the Fillet command and set your radius to whatever you want. Since you were already using an arc, I assume that's what you want. To get the points the arc meets the sides to be smooth, the arc radius must be the same as the distance the "Tangent points" are away from the corner. They then meet the arc (or fillet) at exactly the 90deg point making them "Tangent". Sometimes, when I don't want to bother changing my radius in the fillet command (if I am using fillets of common radius all over the place), I merely put an arc at my corner without caring too much about what the radius is. I then grab the middle grip along the arc and pull it in until it is the correct radius. If your 2 tangent points are not the same distance from the corner, you cannot use a single arc and have smooth transition points. You will then need two or more arcs, or an elipse, or a spline. Quote Link to comment Share on other sites More sharing options...
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