topic Centrelines/Loft on tapered part in Inventor Forum

Centrelines/Loft on tapered part

Anonymous — Wed, 30 Nov 2016 16:53:48 GMT

Dear inventor users! I'm trying to create centre lines on a tapered trapezoidal shaped part (attached). I created the tapered shape using a loft, now i am trying to loft 4 tiny squares on the surfaces to make centring lines but its not allowing me to do that.

Any reason why this would be or is there another way of doing this?

Re: Centrelines/Loft on tapered part

Curtis_W — Wed, 30 Nov 2016 16:59:45 GMT

Hi rashpal,

I don't follow the tiny rectangle thought, but try this.

In the browser, expend the Origins folder, and then use the Project Geometry tool to project the planes or axes as needed. This assumes you've centered your part about the part origin. If not you might need to create some work features.

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

Re: Centrelines/Loft on tapered part

mcgyvr — Wed, 30 Nov 2016 17:01:54 GMT

Much easier when you actually attach your ipt file..

Why won't it sweep? because you have projected the ends of the circles too?

So please attach your ipt file. I see no real reason what you want wouldn't work.. But there are also many other methods depending on your needs..

What do you need the centerlines for?

What about just performing 2 splits on the part to break that part/surface up into 4 split segments?

Here is an image showing me its working just fine (feature on right side is a loft) and I also show what the "line" would look like if you just used split (line on top)..

I would post my ipt file but I don't know what version of Inventor you have either and the files aren't backward compatible so if you don't have 2017 you couldn't open my ipt file anyways..

Re: Centrelines/Loft on tapered part

Anonymous — Thu, 01 Dec 2016 11:30:00 GMT

@mcgyvr and @Curtis_W

Thanks for your help. Yes I have inventor 2017 so it would be good if you could attach your file.

Please see my attachment - you can see that there are 4 rectangular shapes, these should be cut through the model. I am also going to need some of these lines running across the model too - with it being an ellipse I can't really revolve around it can I?

If could demonstrate this for me on the model I would be most grateful!

Re: Centrelines/Loft on tapered part

TheCADWhisperer — Thu, 01 Dec 2016 12:27:35 GMT

@Anonymous - what is the correct tap drill size for an M12 hole?

Flat bottom holes (especially deep ones) are expensive to manufacture.

Bottom tapped holes are expensive to manufacture (broken taps).

Tip: Use the Hole feature command to create threaded holes.

Your ellipse sketches are placed at the origin - but not constrained to the origin.

You must have accidentally turned off AutoProject of the Origin Center Point.

Re: Centrelines/Loft on tapered part

Anonymous — Thu, 01 Dec 2016 12:39:22 GMT

Thanks for the tips @TheCADWhisperer

Re: Centrelines/Loft on tapered part

TheCADWhisperer — Thu, 01 Dec 2016 12:53:03 GMT

@Anonymous - Examine the attached file.

Re: Centrelines/Loft on tapered part

Anonymous — Thu, 01 Dec 2016 13:01:51 GMT

@TheCADWhisperer

This is what I was looking for, thank you. How did you angle the extruded lines on the edges?

I am also looking for some lines around the circumference of the ellipse - what method would I use to execute that?

Re: Centrelines/Loft on tapered part

TheCADWhisperer — Thu, 01 Dec 2016 13:11:52 GMT

@Anonymous wrote:

..I am also looking for some lines around the circumference of the ellipse - what method would I use to execute that?

What is the purpose of these "lines"?

The design intent for the lines will determine how I would model them.

Re: Centrelines/Loft on tapered part

Anonymous — Thu, 01 Dec 2016 14:10:22 GMT

They are needed to simply line this part up with another part @TheCADWhisperer

Re: Centrelines/Loft on tapered part

TheCADWhisperer — Thu, 01 Dec 2016 14:51:17 GMT

I don't know what this means.

Can't you simply use the workplanes to line up the parts?

What is the purpose of the real world parts?

What does the other part(s) look like?

Re: Centrelines/Loft on tapered part

Anonymous — Thu, 01 Dec 2016 14:56:18 GMT

@TheCADWhisperer

oh sorry, this will be a part that will be made from plastic by CNC machining...the other part will look exactly the same. Its for a medical device purpose, and so this requires lining it up accurately as possible. The other lines can be made by sweep I guess....but how did you angle and extrude the other lines that you put on already?

Re: Centrelines/Loft on tapered part

mcgyvr — Thu, 01 Dec 2016 15:11:36 GMT

@Anonymous wrote:

@TheCADWhisperer

oh sorry, this will be a part that will be made from plastic by CNC machining...the other part will look exactly the same. Its for a medical device purpose, and so this requires lining it up accurately as possible. The other lines can be made by sweep I guess....but how did you angle and extrude the other lines that you put on already?

@Anonymous Rashpal... You have the file from him.. Simply edit the sketch of each feature to see EXACTLY how it was done..

Having the actual part is better than him writing a paragraph about how it made it..

The sketch is not angled at the top and extends above the boundaries of the part.. But it doesn't matter.... Just look at them..

Edit the sketch or right click on the sketch and select "visible" that will show you the exact lines he sketched to achieve the outcome..

And remember its a "cut" so its ONLY removing material thats already there.. It doesn't matter if the sketch is taller or whatever as it can only remove existing material..

Inventor is smart enough to know that if there is no existing material there that it only removes material thats there..

Here is an example of what I'm talking about..

The "blue lines" are the sketch used for the cut.. It doesn't matter that the sketch is hanging in the air there and barely on the part.. Its ONLY removing material where material is..

Re: Centrelines/Loft on tapered part

Anonymous — Thu, 01 Dec 2016 15:43:57 GMT

@mcgyvr

Thanks for the useful tips, makes sense.