Bell Roof

[sdsinc]

Hello fellow Chiefers:

I am stumped. Have tried to do this bell roof with roof planes, solids, and moldings but I simply can't get it right. There are multiple pitches on this as the center of the peak is not the center of the arc its covering. If anyone can help it would be so appreciated. I am sure someone will yell "sketchup" but I am not skilled enough with that program to attempt this.

Thanks,

Rich

[dshall]

I will give it a try in the AM. The Great David Michael can probably do it with his eyes closed. I would assume if you can get one plane correct, it is simply a matter of the T/R tool. To get that first plane correct I would assume it is a CURVED ROOF but instead of a POSITIVE CURVE, you would need to make it a NEGATIVE CURVE, and you would need to work on the pitches at the eave and the ridge.

[dshall]

Let me back up, going from memory, draw a roof plane, get your fascia and ridge hts correct, open roof dbx and check curved roof and now for the pitch (or angle) it should probably be a negative pitch, a positive pitch would give you the dome effect, a negative pitch should give the inverse.......... going off memory, I will try in AM.

[dshall]

Hey Yusuf, this is right up your alley.

[sdsinc]

The curved roof part is correct - by selecting a ridge angle of 90 it will create the curve - let me explain what I did:

I first created an arc that matched the window shape. I brought that into a separate file and using the arc created a curved wall and then gave it two sides and a back (to create a room). I then created a second floor that did not include the curved wall. I can then autobuild the roofs and get a standard boring radius roof that is isolated to the first floor above the bow. Pitch was 20:12 and segments were 7 1/2 degrees rather than the standard 15.

Now I have the static roof - so I take the two middle planes (which are the tallest) and I convert them to curves with ridge angle of 90. That works ok - but when you try that with the adjacent planes, which gradually are smaller as you get to the ends, pythagoras kicks in and the numbers start going crazy - with complex stuff my brain cannot work out. And the roof planes then do not join and begin to do strange things. I also think when I look at the picture that the very end is somehow turned back in at 90 degrees to get the look right.

So I thought solids would work but its very labor intensive - it takes about an hour to create the roof using solids and if I have to change it I can't because solids don't like to be scaled. Even after the hour its still not "right"

But thanks for the quick reply! - BTW I'm on X5 - did not update my status.

[dshall]

It sounds like you are on the right path. But I would argue with your statement that each successive roof plane gets shorter. I would think every roof plane is the same with the exception of the two planes at each end which maybe half the width of the others.

[dshall]

On second thought, I may understand the Pythagoras issue....... Dog gone it, this is a good one.

[dshall]

I took a look, I have not idea how to do this.

[McQueen3D]

I wonder if you could make a molding profile with the cross section of the roof and make a molding polyline and tweak it so that it fakes a roof?

[HumbleChief]

Wow That's a good one. I kinda sorta got some roof planes to kinda sorta look like the OP's Bell Roof but kinda sorta is being kinda sorta kind about the attempt. I could find no way to actually join the roof planes.



Plan here which may or may not help.

Bell Roof 2.zip

[dshall]

I wonder if you could make a molding profile with the cross section of the roof and make a molding polyline and tweak it so that it fakes a roof?

I thought of that. The problem with that it gets back to the idea that is is an ever changing pitch because the center point of the roof is not in the same location as the center point of the bow window.

[yusuf]

ok rich, does this similar to your need, you did it as i c the pictur, or am i missing the exact problem to be solved?
http://www.chieftalk.com/attachment....0&d=1352935240

[VHampton]

That's close Yusuf but the bay window is an ellipse not a half circle. That's why the molding method can't work as Scott pointed out.

I think Larry is on the right path.

maybe this could work?...

Try making a room shaped liked a football in a separate plan.
(Use the same arc for the room perimeter as your eliptical bay is using.)

Set the pitch on the auto roof at something steep ....like 30 in 12.

Copy half of the auto generated roof and paste it into your plan over the bay.
Maybe it can be shaped against the gable end wall by making each section hit at the center.

It's going to be tough because there's a lot of manipulating involved. And it probably won't match but at least you could place a roof over the bay.

The 2D views can be faked with CAD work.

[yusuf]

hmmm thanks. My assumsion was correct. You verified
Thanks vhampton. Already posted here.
http://www.chieftalk.com/showthread....373#post457373

[Gene Davis]

Seems to me as if there is roof shape warping going on. It is most apparent in the copper-roofed segments that lie against the wall. Chief cannot do warped roofs. You can model such a thing in Sketchup and import it. Good thing you don't want to shingle-texture it. Chief would make a mess of that, as the surface is all triangulated as is a terrain surface.