AutoCad puzzle.

cgarrad · 13-05-2013 1:53am #1

How do you draw this in autocad?

Only have AutoCAD 2005 btw (hanging head in shame...)

toastedpickles · 13-05-2013 1:57am

What's it supposed to be firstly?

cgarrad · 13-05-2013 2:01am

Part of a site. The rest is even more complicated, should be able to do it if I can do the first bit I'm thinking ;-)

Celly Smunt · 13-05-2013 2:01am

You could do it old skool with a bit of trigonometry and a calculator to get your angles.

toastedpickles · 13-05-2013 2:03am

It's a feckin awkward yoke isn't it?

I've it drawn here on mine (2011) and it's not adding up at all, does it taper in or anything?

cgarrad · 13-05-2013 2:06am

toastedpickles wrote: »

It's a feckin awkward yoke isn't it?

I've it drawn here on mine (2011) and it's not adding up at all, does it taper in or anything?

It was done with a surveyors tape (50m) so should be fairly accurate.

That said, I did not do it but I know the guy and I'd trust his measurements normally...

cgarrad · 13-05-2013 2:07am

pmcmahon wrote: »

You could do it old skool with a bit of trigonometry and a calculator to get your angles.

No way of making AutoCAD do this? The other measurements are much more complex ;-)

toastedpickles · 13-05-2013 2:09am

cgarrad wrote: »

It was done with a surveyors tape (50m) so should be fairly accurate.

That said, I did not do it but I know the guy and I'd trust his measurements normally...

It doesn't match up, I'd measure it yourself again, just to be sure, can never trust surveyors in my opinion

But does the site taper in or anything like that? or is it just a rectangle?

Celly Smunt · 13-05-2013 2:24am

cgarrad wrote: »

No way of making AutoCAD do this? The other measurements are much more complex ;-)

Not that i'm aware of,though i'm by no means a CAD expert :pac:

Cedrus · 13-05-2013 2:29am

I'd draw the bottom line 9400 first.
Then centre a circle at each end, radius 12550 on the left and 17650 on the right then osnap a line from the left end of the first line to the intersection of the circles. delete the circles. Left perimeter done.
Repeat for the 12000 & 13950 dims and you have the right perimeter.
Osnap a line from the ends for the lane perimeter and if its 5650 the surveys good.

There's probably a quicker way but I'm old school.

cgarrad · 13-05-2013 2:30am

Used this to get the angles

http://ostermiller.org/calc/triangle.html

Back in 10 ;-)

cgarrad · 13-05-2013 2:31am

Cedrus wrote: »

I'd draw the bottom line 9400 first.
Then centre a circle at each end, radius 12550 on the left and 17650 on the right then osnap a line from the left end of the first line to the intersection of the circles. delete the circles. Left perimeter done.
Repeat for the 12000 & 13950 dims and you have the right perimeter.
Osnap a line from the ends for the lane perimeter and if its 5650 the surveys good.

There's probably a quicker way but I'm old school.

Great idea ;-)

cgarrad · 13-05-2013 2:53am

Not too bad but not correct.

Other ones are not possible without more measurements though.

cgarrad · 13-05-2013 2:57am

No DWG support so zipped it.

Supertech · 17-05-2013 8:19am

Cedrus wrote: »

I'd draw the bottom line 9400 first.
Then centre a circle at each end, radius 12550 on the left and 17650 on the right then osnap a line from the left end of the first line to the intersection of the circles. delete the circles. Left perimeter done.
Repeat for the 12000 & 13950 dims and you have the right perimeter.
Osnap a line from the ends for the lane perimeter and if its 5650 the surveys good.

There's probably a quicker way but I'm old school.

^^This is the correct way to do it.

It looks to me like you need more diagonals on the survey, and, if it's three parts of the same field, you need some diagonals to tie the individual parts together. If not you'll carry errors from one section of the survey to the next, and the survey won't line up correctly.

Incidentally, when I draw the first part starting from the 9400 dimension and working anticlockwise, I'm getting a 100mm error when I close the perimeter and check the last diagonal - that's not too bad for a survey done with a tape - you'll rarely get a taped survey to close completely.

EmmetF · 24-05-2013 9:51am

Supertech wrote: »

^^This is the correct way to do it.

It looks to me like you need more diagonals on the survey, and, if it's three parts of the same field, you need some diagonals to tie the individual parts together. If not you'll carry errors from one section of the survey to the next, and the survey won't line up correctly.

Incidentally, when I draw the first part starting from the 9400 dimension and working anticlockwise, I'm getting a 100mm error when I close the perimeter and check the last diagonal - that's not too bad for a survey done with a tape - you'll rarely get a taped survey to close completely.

Exactly, I'm getting a 100mm error which is remarakably accurate on a 9.5m measurement (1% error)

Homework attached.

cgarrad · 25-05-2013 4:57pm

Thanks all, circles is obviously the way to go.

Not perfect but close enough ;-)

PrzemoF · 28-05-2013 4:33pm

An easy way to solve something like this is to use parametric CAD like FreeCAD or get familiar with parametric constrains in AutoCAD

AutoCad puzzle.

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