Community
This may be a little difficult. The way it is written it may be referring to the Degree of Curve(ature) rather than the central angle. Additional confusion can come from the fact that there are 2 definitions for Degree of Curve. One was commonly used in highway work the other was used in railroad work.
The roadway definition is the angle that includes an arc length of 100'. The railroad definition is the angle that includes a chord of 100'. Hopefully you can determine which one it may be referring too. Or the writer of the description may have meant the central angle and just wrote it in a strange way.
You can select this while creating the curve from end of object. This is also covered in Help. Search for "degree of curve".
Command: _AeccCurveFromEndOfObject
Select arc or line object:
Select entry [Radius/Point] <Radius>:
Specify Radius, or [degreeArc/degreeChord]: a
Specify degreeArc, or [Radius/degreeChord]: 11.28
Select entry [Tangent/Chord/Delta/Length/External/Mid-ordinate] <Length>:
Specify length of curve: 188.5
Allen
See:http://www.steamlocomotive.com/model/curve.shtml
http://www.dot.state.il.us/desenv/survey/apxa.pdf
http://www.ctre.iastate.edu/educweb/ce353/lec05/lecture.htm
Allen Jessup
CAD Manager - Designer
Did you find this post helpful? Feel free to Like this post.
Did your question get successfully answered? Then click on the ACCEPT SOLUTION button.
BTW: When plotting a deed description I try not to run through the curve if there is only one. I'll run the description from the point of beginning until I hit the point of curvature then I'll run it backwards from the point of beginning to the point of tangency. Then I'll see how the curve will fit. This is because most deeds were written before computers or calculators and most of the error you'll find will be in the curves. If there is more than one curve. I'll skip over the curve, draw the next tangent, draw the radials from the tangents and move the floating tangent and radial to the radius point created by drawing the radial from the inbound tangent. You can't do it this way unless you have a radius. Doing it this way minimizes your error of closure. Allen
Allen Jessup
CAD Manager - Designer
Did you find this post helpful? Feel free to Like this post.
Did your question get successfully answered? Then click on the ACCEPT SOLUTION button.
@Neilw wrote:In my experience the writers of legal descriptions typically do not use arc and chord defined curves so the angle of curve is usually the included angle or the deflection angle
Definitely true. But the way that curve was described is just far enough from what I consider normal that it made me wonder. I'd also expect it to be a non-tangent curve (to the inbound course) since the back-tangent is supplied.
Allen
Allen Jessup
CAD Manager - Designer
Did you find this post helpful? Feel free to Like this post.
Did your question get successfully answered? Then click on the ACCEPT SOLUTION button.
Neilw wrote:
Can you clarify why you think the curve is non-tangent Allen? Also, from the OP I understood that the inbound tangent is provided, not the outbound, since the curve is described as "from a tangent bearing N88-59E for 188.5 feet".
In my experience the only reason to specify a tangent bearing for a curve is if the curve is not tangent to the inbound course. Since a tangent bearing is supplied it makes me suspect that the curve isn't tangent to the previous course. I know that's a lot of supposing from a portion of one line in the description.
I thought the back-tangent was the inbound tangent as in the tangent at the back of the curve. Although I'm just assuming that the PC is the back of the curve. If that's wrong let me know.
Allen
Allen Jessup
CAD Manager - Designer
Did you find this post helpful? Feel free to Like this post.
Did your question get successfully answered? Then click on the ACCEPT SOLUTION button.
Without plotting it I'd say it looks like the parcel cuts across 2 concentric curves. The courses are a little general, so I wouldn't expect a high degree of closure.
Allen
Allen Jessup
CAD Manager - Designer
Did you find this post helpful? Feel free to Like this post.
Did your question get successfully answered? Then click on the ACCEPT SOLUTION button.
I tried plotting this. Fist. Is the 1847.5 feet correct. I don't see how the following courses could bring you back from that far out. I've tried using the angle as the Arc definition and as the central angle. I think that 1847.5' distance doesn't make sense.
Do you have a map that show what the approximate shape of the parcel should be?
Allen
Allen Jessup
CAD Manager - Designer
Did you find this post helpful? Feel free to Like this post.
Did your question get successfully answered? Then click on the ACCEPT SOLUTION button.
BTW This is what I used for the curves holding the 11.28 as the central angle.
CURVE SOLVER RESULTS
------------------------------------------------
Included angle = 11-28-00
Radius = 941.883'
Tangent length = 94.566'
Arc length = 188.500'
Chord length = 188.186'
External secant = 4.735'
Mid ordinate = 4.712'
Degree of curve = 06-04-59
CURVE SOLVER RESULTS
------------------------------------------------
Included angle = 11-28-00
Radius = 527.154'
Tangent length = 52.927'
Arc length = 105.500'
Chord length = 105.324'
External secant = 2.650'
Mid ordinate = 2.637'
Degree of curve = 10-52-08
Allen Jessup
CAD Manager - Designer
Did you find this post helpful? Feel free to Like this post.
Did your question get successfully answered? Then click on the ACCEPT SOLUTION button.
No. It's not the distance. I had one entered wrong. It's in the curve. The age of the document isn't that bad. I work in NY and being one of the original colonies we have some old descriptions. I work with survey field notes over 75 years old in this office.
I haven't done any work in the part of the country that uses sections. Would you have any reason to think the description should hit the east-west section line, as shown in your PDF? Particularly after the 1775.5' line..Right now I have something that looks like the attached
Allen
Allen Jessup
CAD Manager - Designer
Did you find this post helpful? Feel free to Like this post.
Did your question get successfully answered? Then click on the ACCEPT SOLUTION button.
That's how I read it too. After seeing the photo it looks like there is some distance from the section line to the road in question. If you use the tangent as the first course the curve to the left makes sense. Since the description fails. I'm falling back on intent.
Of course if I were doing the Survey we would have field locations and adjacent deeds to help make sense of it. Right now it's just a guess from what I've been shown.
Allen
Allen Jessup
CAD Manager - Designer
Did you find this post helpful? Feel free to Like this post.
Did your question get successfully answered? Then click on the ACCEPT SOLUTION button.
Can't find what you're looking for? Ask the community or share your knowledge.
Post to forums
![Autodesk Design & Make Report](https://forums.autodesk.com/t5/image/serverpage/image-id/1350519iCB55845EBFC43016/image-size/large?v=v2&px=999" "Autodesk Design & Make Report")