Split fails and I don't see why

marchal_sebastien

Hello,

I have smething that seems weird to me: in I can't get this split to work:

the document is here: https://cad.onshape.com/documents/b84993bfd4616049d5cec857/w/8720bc7db7e9a32fa111f2c1/e/c0bc29226f43f71a336aae3b

Any suggestion on what is wrong is velcome !

jelte_steur814

@MDesign was right though:

if you turn curvature color map on, there's something strange going on still. this 'fold' starts in the area where the split was going to be.

i tried splitting with an offset plane and at an offset of 15 mm it starts working.

try playing with Connections in the loft that creates it:

jelte_steur814

the guide curves indeed also create a weird kink because they're not normal to profile/tangent to wing surface.
so I unchecked those.
works here:

https://cad.onshape.com/documents/e920b19fd2804eb5de8a06f6/w/5650947d4be38681b2f03ad5/e/1946924e0d58f2949fc0d808?renderMode=0&tangentEdgeStyle=2&uiState=67e6cfdc009baa4e28b1eec4

MDesign

Probably need to clean up this area of your part. smooth that out and it should help.

marchal_sebastien

Hello

Thanks for the suggestion - I needed to clean that up anyway it is a wing after all. It did not fix the issue:

If I use an orthogonal plane, it accept the split. With the one shown "SectionneurSaumon" nope. Still the same document - I will see if the issue arrise as soone as I angle the plane.

marchal_sebastien

I did clean that up and could not get the split to work. I think this is a bug. The failure occurs when the plan angle is to sharp.

I replaced that with a removal extrude and it work - although this is time consuming.

Thanks for the assistance anyway.

MDesign

It does feel buggy. Not sure who needs to know to confirm.

jelte_steur814

@MDesign was right though:

if you turn curvature color map on, there's something strange going on still. this 'fold' starts in the area where the split was going to be.

i tried splitting with an offset plane and at an offset of 15 mm it starts working.

try playing with Connections in the loft that creates it:

MDesign

I tried playing with connections. the issue is the end profile from the loft doesn't produce a nice surface transistion. If I redefine the sketch to be cleaner I can get the split to work but that seems like not the right thing to do.

jelte_steur814

the guide curves indeed also create a weird kink because they're not normal to profile/tangent to wing surface.
so I unchecked those.
works here:

https://cad.onshape.com/documents/e920b19fd2804eb5de8a06f6/w/5650947d4be38681b2f03ad5/e/1946924e0d58f2949fc0d808?renderMode=0&tangentEdgeStyle=2&uiState=67e6cfdc009baa4e28b1eec4

marchal_sebastien

thanks a lot

to summarize my loft is badly formed. I will take care of that better using your inputs.

marchal_sebastien

Hello,

I recreated the wing entirely in a new Part studio, and I used more Spline Guides to force a simpler shape. It works and I am happily splitting every where. Thanks for the support, and I extract from this that "true" loft shape needs to be trippled checked.

Thanks again.