Surface Mastery Part 9 - Patching a Surface using Interior Guide Rails | LOFT VS PATCH VS LOFT...

In this video we are going to again compare the Loft tool to the Patch tool when filling in a surfacing and using interior guide rails. Unfortunately the 3 methods we are going to use will all give different results, but knowing that will help decide which method is right for your project.
If you want to follow along you can download the dataset here: a360.co/3GbSYU8
The methods we are going to look at are:
1. Patch using curvature continuity and 2 interior rails
2. Loft using curvature continuity and 2 side rails and 2 interior rails
3. Loft in multiple sections with Patch to fill in gaps.

[@janosadelsberger]

I learned that you’re supposed to use Loft for four sided surfaces and patch for three or more than four sided surfaces because Loft creates an untrimed surface while Patch overbuilds and trims the edges of an underlying four sided surface.

[@LearnEverythingAboutDesign]

Great comment and great tip!

[@mikiauto73]

Thanks!

[@benb5841]

I do a lot of surface modelling. So many new ideas here for how to do it. Thank you!

[@LearnEverythingAboutDesign]

Happy to help!

[@mikiauto73]

Great videos, thanks!

[@LearnEverythingAboutDesign]

You're welcome!

[@jamesthompson4062]

Thanks for doing these tutorials 😎

[@LearnEverythingAboutDesign]

Glad you like them!

[@hveguitar]

Love your tutorials, thanks so much!

[@LearnEverythingAboutDesign]

Thanks for watching!

[@1pixle]

Thankyou for this

[@LearnEverythingAboutDesign]

You are welcome!

[@bwilliams1815]

Matt. I like the last example because of the continuous blends from top to bottom. You mentioned at the end about using the Ruled Surface tool. I was thinking that because of the draft option. Many times in molding application we need to add draft angles to release the part. I was wondering how you would add draft angles on the example you gave. Thanks again for the discussion and illustration.

[@LearnEverythingAboutDesign]

Good point! Sounds like a good topic for the next video. Typically i would make "helper" surfaces to help control the draft direction. I will try to outline that for complex shapes in the next video!

[@sadhucat4476]

You've mentioned class A surfaces a couple of times now. Where would this level of smoothness be needed? Fluids stuff and aerodyamics?

[@LearnEverythingAboutDesign]

Typically Class A is used for Automotive, Planes etc. Consumer products "can" use it but many are made with traditional CAD packages. You basically have better control over surfaces and the ability to maintain a higher level of continuity. Most CAD programs will have G0 (coincident), G1 (Tangent) and G2 (Smooth). Class A programs introduce G3 which looks at the tangency direction (G1), the radius of curvature (G2) and the rate of change or acceleration. This equates to derivatives if you think about direction, speed and acceleration. So if you think about an Arc that has a constant rate of change. But if you have a spline it might be increasing or decreasing its radii as it gets to the edge. G3 looks at that.

[@utkusonmez5674]

Is there any video from you that teaches how to model the very first desing it self ?

[@LearnEverythingAboutDesign]

That first surface was done with a Form. There isn't a video for that specific one but you can download the dataset and edit that purple feature in the timeline. I have tons(probably over 100) videos on form modeling so if there is something specific you are trying to model there might be a video dedicated to it.