Skip to main content
L
LL_106628384-Participant
4-Participant
September 8, 2023
Solved

Sweep with two trajectories and multiple sections

  • September 8, 2023
  • 5 replies
  • 4083 views

Hello, I am trying to create this handle in Creo v.9. 

LL_10662838_0-1694164608661.png

 

My plan was to do the "bend" as a sweep. However I can not manage to do this. I have created a sketch with the outer countor, as you see on my picture below. But what I need help with is which sweep to use and how to create the right cross section at the right point ( the green part in the drawing).

 

I will also upload the part-file. 

LL_10662838_1-1694164758014.png

 

 

 

 

 

Best answer by tbraxton

An arguably simpler way to realize the geometry is to use two extrusions and apply the rounds. Sketch 1 is only there because it was in the model already. See video below for sequence. I would agree with @pausob that CREO ISDX features would probably be used to design this if it was subject to Industrial Design approval, especially if it had a high gloss finish.

 

Note that this geometry does not have all of the isoparm lines generated by the boundary blend features internal to each boundary blend and more closely matches what I assume are the tangent edges in the reference drawing. This may be more stable in the context of the model accuracy, not sure since we always use absolute accuracy in start parts.

 

tbraxton_0-1694407911052.png

 

5 replies

M
MatthewV9-Granite
9-Granite
September 8, 2023

Hi !

 

I believe you could achieve that with a boundary blend. Maybe follow a bit this tutorial. Around 10mins this becomes interesting for you.

 

https://community.ptc.com/t5/Creo-Parametric-Tips/Creo-Surfacing-Tips-Techniques-Session-Recording-East-Coast/ta-p/820856#M729

T
22-Sapphire II
tbraxton22-Sapphire II
22-Sapphire II
September 8, 2023

Here is an example of one way to do it using Creo core surfacing (boundary blends). This is not the only way to do it. Creo 7 model enclosed for reference. I did not verify the geometry matches the drawing exactly so check that yourself. 

 

I think it is possible to use the variable section sweep feature and would encourage you to try it that way as well.

 

 

tbraxton_1-1694182769928.png

 

L
LL_106628384-ParticipantAuthor
4-Participant
September 11, 2023

Thanks so much! I will try myself to build it like you did. 

 

P
19-Tanzanite
pausob19-Tanzanite
19-Tanzanite
September 10, 2023

I feel this model has been "made up" to showcase the Creo rounding capabilities.  Although it is quite impressive what can be done with variable-section sweeps and rounds in this software, I think this example shows the shortcomings of using the "basic tools" for industrial design - in that the finished shape seems rather awkward and amateurish.

  

Anyway, I think I achieved my goal of reverse-engineering this part, but to reiterate, there are better tools and methods based on boundary blends and  use of the ISDX (surface design extension) for these types of parts.

 

round_testround_test

 

Also note the attached models are rather "flaky" and needed some strange hacks to finish it.  These are silly things such as fooling around with absolute accuracy (ended setting it to 0.001)  and building half the model, then quartering it and then restoring the full shape.  Or this 2nd version (made with default relative accuracy of 0.0012) - but in which the order and methods of mirroring mattered for the ability to regenerate it.

round_test_2round_test_2

 

And if you change the part accuracy, the rounds will start failing.  So another example of why I don't like these fancy rounds, but good to know they are there.  Lmk if you try them and they work better in Creo 10 (these were made in Creo 4) 

L
LL_106628384-ParticipantAuthor
4-Participant
September 11, 2023

Thanks! This was very helpful, I learn so much from seeing how you built it and managed to build it myself now!

T
22-Sapphire II
tbraxton22-Sapphire IIAnswer
22-Sapphire II
September 11, 2023

An arguably simpler way to realize the geometry is to use two extrusions and apply the rounds. Sketch 1 is only there because it was in the model already. See video below for sequence. I would agree with @pausob that CREO ISDX features would probably be used to design this if it was subject to Industrial Design approval, especially if it had a high gloss finish.

 

Note that this geometry does not have all of the isoparm lines generated by the boundary blend features internal to each boundary blend and more closely matches what I assume are the tangent edges in the reference drawing. This may be more stable in the context of the model accuracy, not sure since we always use absolute accuracy in start parts.

 

tbraxton_0-1694407911052.png

 

    L
    LL_106628384-ParticipantAuthor
    4-Participant
    September 11, 2023

    Thank you so much! This is for sure the easiest way to achieve the model! 

    P
    Patriot_177622-Sapphire II
    22-Sapphire II
    September 13, 2023

    Man, this is an ugly handle, but, thought I'd try something to see if it worked (it did).  I didn't bother to put the mounting holes in because I wanted to test something else.

    PTC_HANDLE-01.png

    P
    Patriot_177622-Sapphire II
    22-Sapphire II
    September 14, 2023

    Thought I'd make a better looking (i.e. less fugly) handle for fun.  Still has the hard 6mm radius at the bottom, but blended to it at sort of an angle and made the bottom oval instead of obround.  Didn't bother putting mounting holes in.  Interesting little distraction on a boring day...

    PTC_HANDLE-02.png

    Terms & ConditionsCookie settingsAccessibility statement