Author Topic: Passenger car roof  (Read 1426 times)

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Chris333

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Passenger car roof
« on: August 10, 2021, 01:46:22 AM »
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How do I proceed with increasing the pressure in my skull?


peteski

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Re: Passenger car roof
« Reply #1 on: August 10, 2021, 04:09:38 AM »
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To me it looks like you have the highest "skull pressure" part already resolved (the complex curve of the clerestory end).
. . . 42 . . .

Chris333

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Re: Passenger car roof
« Reply #2 on: August 10, 2021, 05:39:54 AM »
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The arch of the top part was consistent so I just copied the arch and connected the dots.

The corners bend 2 ways.

Lemosteam

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Re: Passenger car roof
« Reply #3 on: August 10, 2021, 07:02:27 AM »
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The arch of the top part was consistent so I just copied the arch and connected the dots.

The corners bend 2 ways.

Ahhh, complex surface modeling.

Can you create surfaces using edges?  If so extend the two edges (rear edge and bottom of clerestory near the end) till they intersect.  Using the four curved edges as boundaries, let the tool develop the resulting curvature of the surface.  If the tool has the capability, it will try to create a surface that blends smoothly from each opposing curve in both directions (basically an average).

If you cannot get it to work email me a step file and I will try to complete the corner for you and send it back as a step file.
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Chris333

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Re: Passenger car roof
« Reply #4 on: August 10, 2021, 07:49:41 AM »
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I think they call that "hand stitching" in Sketchup. All 4 edges are different and if I just stitched them together it would be flat and not follow the curves.

It would look something like this hot mess:


I guess it will have to work since it will need a light sanding anyways.

Ed Kapuscinski

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Re: Passenger car roof
« Reply #5 on: August 10, 2021, 09:27:14 AM »
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Just add plenty of material to sand through.

I mean, the real cars were hand built...

nickelplate759

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Re: Passenger car roof
« Reply #6 on: August 10, 2021, 09:47:01 AM »
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What you want is a splined surface.  Professional CAD software (e.g. Solidworks) has built-in  support for this.  I'm guessing Sketchup may not?
George
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I'm sorry Dave, I'm afraid I can't do that.

ednadolski

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Re: Passenger car roof
« Reply #7 on: August 10, 2021, 10:13:08 AM »
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What you want is a splined surface.  Professional CAD software (e.g. Solidworks) has built-in  support for this.  I'm guessing Sketchup may not?

Caveat, haven't tried this myself:   
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Also, WRT intersecting faces:
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Ed

Lemosteam

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Re: Passenger car roof
« Reply #8 on: August 10, 2021, 11:22:10 AM »
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I think they call that "hand stitching" in Sketchup. All 4 edges are different and if I just stitched them together it would be flat and not follow the curves.

It would look something like this hot mess:


I guess it will have to work since it will need a light sanding anyways.

Once you have a solid, see if you can add a fillet along the edge where the two surfaces meet.  Not sure if the tool has a variable fillet, i.e. R0.001 at one end, R3 in the midpoint and R0.001 at the other end.

bbussey

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Re: Passenger car roof
« Reply #9 on: August 10, 2021, 02:41:53 PM »
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Yeah, clerestory roofs are a pita.  Do you have the ability to loft from one sketch to another with guidelines in SketchUp?  What I generally do is create the lower roof and clerestory roof as separate bodies, then combine them into one body and shell out the bottom.  Then you only have to worry about one set of complex ends at a time.
Bryan Busséy
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Chris333

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Re: Passenger car roof
« Reply #10 on: August 10, 2021, 03:51:29 PM »
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In the end I just did the one corner shown and then mirrored/flipped it to make another half and joined them. That little corner probably took me 45 min to "freestyle" like that.

I now know the intersecting faces and use it a bunch, but here if I pulled 2 surfaces I could join them, but then they wouldn't match the other 2 surfaces.

wcfn100

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Re: Passenger car roof
« Reply #11 on: August 10, 2021, 03:54:59 PM »
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I thought Sketchup had an 'Extend' functionality where you could take that edge a extend it to the end of the car.

Jason

Chris333

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Re: Passenger car roof
« Reply #12 on: August 10, 2021, 06:37:58 PM »
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I've extended an edge before, but not on a twisted arch.

u18b

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Re: Passenger car roof
« Reply #13 on: August 17, 2021, 09:46:12 AM »
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Hi hope @chessie system fan is watching.

We discussed this issue not that long ago.
Ron Bearden
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"All get what they want-- not all like what they get."  Aslan the Lion in the Chronicles of Narnia by C.S.Lewis.