Taper to create sloped wedge indentation on edge segment

[MargaritaErem]

Hello,

This is a re-post- so I'm sorry if this violates the forum rules- but I didn't get any replies in the beginner's area- and I've been trying this on my own for a some time and really need help.

 

I am a complete newbie- been using AutoCAD for 3 days with a free trial that I got for a one time project. I'm sorry if this thread is a repeat of other topics- my searching ability is limited because of my lack of knowledge of terminology.

 

I need to create a 3D model of a segment of a jogging path/trail that has a drainage feature called a knick. I pasted a freehand drawing of what a knick looks like below this post. It's a semi-circular area that slopes to one side at a small angle on a trail that is otherwise flat. I need a model of a trail segment with two of these sloping indentations that is just a smooth, gray object- nothing fancy. I managed to create a simple 3D model for a second trail design that has a slope to one side throughout the trail- made a box with a tapered edge and rendered it gray.

 

Since to my eye a knick looks like a lemon wedge indented into the face of a box- that's what I've been working towards. Made a box, made a cylinder, moved the cylinder so half of its base sits on top of the box face on which I want the indentation, and then used pushpull and subtract to take out a shallow semi-circular cut off the top of the box (did two of these about 20 units apart on the same face).

 

Here is where I ran into my own limitations. I don't know how to taper the semicircular cut so that it actually slopes off the face to the edge and doesn't look like a clean cut depression. I need it to slope to the edge at a 2% angle. I've tried tapering many times, but I don't think I completely understand the concept of the tapering axis (or rather I know that I completely misunderstand it) because all I end up doing is tapering the various faces of the box and the knick cut stays the same. I also tried out all the tools on the ribbon that look like they can be used for filling in or smoothing edges, but without any luck. Can someone point me in the right direction on this tapering process? Or should I be approaching the process of making the knick from a completely different set of commands?

 

I am sorry I can't attach what I've done so far- I don't seem to have uploading ability.

 

I appreciate any help or advice.

Thank you.

-Margarita

 

knick:

[ReMark]

You're basically trying to create a wedge with a curved edge right?

[MargaritaErem]

Yes, essentially. For lack of a better description, it should look like the side of a bagel was impressed into the edge and made an indentation on the top face of the box. Hm. As I was typing a response, I thought of something that I haven't before for some reason- to impress the side of a sphere on the box. I will try that right now and post back if I have any luck in coming close to what I need.

 

Thanks for your reply!

[nestly]

Anything like this?

 

[MargaritaErem]

Anything like this?

 

[ATTACH=CONFIG]42983[/ATTACH]

 

Wow! I guess I have a long way to go before I can do something like that.

But no- that's not the cross section that I need. I need the depression on the side of the trail- so it's flat everywhere outside this semi-circular region. I am sorry that I still can't upload. I could have shown you my approximation with a subtracted cylinder.

I am now trying to do the same technique but subtracting a sphere from a box.

Thanks for the reply!

 

[nestly]

Did you try the "Manage Attachments" section on the advanced reply page?

[MargaritaErem]

I did. That's where it won't let me upload anything. I choose the files and hit upload and it just sits there...

[Cad64]

How large is the file you're trying to upload?

[steven-g]

This illustrates the idea better. The image came from a document here which gives a good description.

http://www.activevalley.org/SORBA/Examples%20of%20Normal%20Maintenance.pdf

[ReMark]

Anyone in Europe hear about permeable running tracks? Eliminate the need for something like that altogether.

Edited July 18, 2013 by ReMark

[ReMark]

Would something like this rough approximation do?

[ReMark]

Still a rough approximation but might this be closer to what you are looking for?

[ReMark]

Front view of the previous idea. Kind of a scalloped affect.

[ReMark]

Last attempt. A knick with a lip!

[MargaritaErem]

THANK YOU REMARK! It took me a long time last night but I got something that is very close to the third drawing that you posted. It has a lip that leads to a side ditch which, I am proud to say, I also managed to create.

Thank you for all the effort you put in your replies! Even one visit to this forum really helped me!

-Margarita

[MargaritaErem]

Permeable trails still need drainage curvature and hard packed dirt trails are the most environmentally sustainable- that's why dirt trails are still around. Landscaping plastics and paving materials all leach toxins into the ground water and can't be used in areas that are close to wetlands, which this trail is (this is in the US).

Shovels and mulch will never go out of style!

-M

[ReMark]

Had I known you already figured it out I would have gone for a walk along the river or another cup of coffee! LoL

 

I admire your perseverance Margarita. Care to share an image of your design with us?

 

You're entirely welcomed.

[MargaritaErem]

Had I known you already figured it out I would have gone for a walk along the river or another cup of coffee! LoL

 

I admire your perseverance Margarita. Care to share an image of your design with us?

 

You're entirely welcomed.

 

I'm sorry that I was the cause of you missing out on a walk (though not so sorry about the coffee- you should be thanking me for that!)

I am having some trouble copying from autocad (just pastes a white box for some reason), so I am sharing a screen shot. Thanks again!

 

 

[MargaritaErem]

Hm. I guess the screen shot isn't pasting either. Not a good day for me and autocad...

[ReMark]

Images must be attached. You cannot just copy and paste an image to your post. Start by clicking on the Go Advanced button and look for the paper clip icon at the next screen. Find, upload then attach your image.