Creating a corner profile using points

I am in the process of designing an iphone case for a client of mine.  I downloaded a few CAD files of the phone from online only to see they they were not 100% dimensionally correct.  I have found Apple's Design Criteria handbook for cases which lists dimensional drawings for each of their phones.  On the drawing, the corners and edge profile are not specified by a radius, but by a coordinates that create the profile.

 

I put the points in using a sketch, then I want to connect the points to where they are all tangent. I tried using the curve tool, but the curve was never tangent at the edges of the phone profile.  So I used 3 point-arcs between each two points and made them tanget to one another.  Problem is, it always leaves one set of arcs that are not tangent to each other. 

 

Is there a way to create a smooth corner profile that will be tangent to the phone edges?

 

See attachments for what I am talking about. 

Owner: Scott Lester Drafting & Design
Designer: Rotork Instuments
10 REPLIES

Re: Creating a corner profile using points

Or better yet, if you have an excellent source for the CAD model...lol

Owner: Scott Lester Drafting & Design
Designer: Rotork Instuments

Betreff: Creating a corner profile using points

Honored Contributor
Honored Contributor

Hi @scott_lester

 

 

 I'm not absolutely sure wether I have understand You correctly or not, but what speaks against using a tangent relation for the curve?

 

See picture and attached part with sketch.

 

For me this exactly what You show or better to say what You want

 

20161117_1954.PNG

 



regards
Wolfgang

Betreff: Creating a corner profile using points

I cant open your file, you must be on ST9.  Can you post a quick video.  but I think you do have what im looking for.  I just couldnt get my curve to be tangent with both edges

Owner: Scott Lester Drafting & Design
Designer: Rotork Instuments

Betreff: Creating a corner profile using points

when I draw the curve then apply a tanget relationship to the edges, it turns my sketch gray like something is wrong with it.

Owner: Scott Lester Drafting & Design
Designer: Rotork Instuments

Betreff: Creating a corner profile using points

Honored Contributor
Honored Contributor

Hi @scott_lester

 

 

 

yes it is a ST9 file.

But it is simply a tangent relationfrom the curve to the construction line.

 

I will provide a video when being in the office tomorow morning. 



regards
Wolfgang

Re: Creating a corner profile using points

Honored Contributor
Honored Contributor

If arc's can't get it done with the requirements, Then first order curves with tangent restictions are not the specified shape. As a result you need 3rd or 4th or 5th ordered curves. You will need to dig into the curve command rather than use arcs. If this curve command does not have what you needs, then you are out of luck.

 

This is where class A surfacing packages like Imagware come into the picture. It's part of the NX series.

Re: Creating a corner profile using points

That may be the problem, I dont use surfacing or the curve feature much, so I am a bit of a noob when it comes to that. I seen in the options that there was an option for degrees of the curve, but I was not sure what they done.

Owner: Scott Lester Drafting & Design
Designer: Rotork Instuments

Betreff: Creating a corner profile using points

I was able to work around it.  Instead of making it tangent with the sides, I drew construction lines that were colinear with the sides and then made the curve tangent to those and it works.  Im not sure what the difference was though; my curve didnt change gray like before.

Owner: Scott Lester Drafting & Design
Designer: Rotork Instuments

Betreff: Creating a corner profile using points

Honored Contributor
Honored Contributor

Hi @scott_lester,



so You have done it already?

Do You need the video?

 

But I think to add additional lines (as I did) is the point.

 

Maybe the curves form the original edges are also with higher order and maybe this is the reason that You can not make tnagent them with another curve.

 

I will test this and give You the results

 



regards
Wolfgang