T-Spline surface is invalid

[Anonymous]

I am very new to fusion and just started learning the ropes a few days back. This is a project that I have been trying to do for school in the past 3 days and now, I have gotten stuck at an error message on the sculpt tool saying T-Spline surface is invalid and the model will not display in parametric form whenever I clicked finish form. I have tried doing what every youtube video has said and forums from repairing body to changing the display mode. 

I would be really grateful if someone could help me with this and at least nudge me in the right direction.

Thank you,

Rangaraajan 

[TheCADWhisperer]

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@Anonymous wrote:

 This is a project that I have been trying to do for school... 

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Did you design this entirely from scratch, or are you attempting to follow instructor supplied instructions or other reference material (like a YouTube tutorial)?

[Anonymous]

I did this from scratch, designing sketches and using free foam and learnt the basics of using fusion 360 and watched a few videos from youtube of how to go about designing a car model.

UPDATE: I have tried reducing the number of edges and simplifying it a bit but still getting the same error

[judah.kuth · Accepted solution]

I believe the issue is that you have faces that have more than 4 edges.  These are usually called ngons, for polygons with n sides, n being a number other than 4.  You can use the insert point tool to divide faces with more than 4 sides.  I'm attaching two files to show you what I mean: 4x4 1 shows your full model where I started to fix one side of the front so you can compare the two.  In 4x4 2 I fully repaired a quarter of your model and deleted the rest.  You can use Repair Body under Utilities to show you which faces are ngons I hope this helps!

[Anonymous]

Thank you soo much for explaining the reason behind the problem and showing me the right way to do it. Thanking you once again for taking your precious time to answer my question.

[Ajay_Kumar_Reddy · Accepted solution]

Hey @Anonymous,

You did great in design.

but there are certain rules for sculpting.

for this particular case you have created

3, 4, 5 even 6 sided face which is not good at all.

you must use 4 sided face whenever possible in that way the topology will work.

here I'm attaching the screenshot.

I would recommend you to build it from scratch, creating only 4 sided faces.

[Anonymous]

Thank you, will keep the rule in mind and do it again.