Modeling Spiral Roof

[AliaJB]

@Kevin K 

Edited March 23, 2021 by Alia Brookshire

[line-weight]

Stepping a little outside the scope of what we've actually been asked to comment on.... I would say that whenever something is a nightmare to model, it's quite likely it'll be a nightmare to build too. Put another way, if it's difficult to define to Vectorworks what needs to happen then it may be difficult to define to a builder too.

 

If this gets built will it be a perfectly smooth curved plane? Probably not - it will probably be faceted in some way. Therefore, it may make sense to thing of it constructionally and therefore model it faceted from the outset.

 

Facets will not easily work where you have double curvature - but if you end up with double curvature it might be a clue from the modelling gods that the roof design is not feasible.

 

I realise this may be unwelcome commentary!

[AliaJB]

@line-weight You're definitely hitting the nail on the head there- not unwelcome commentary at all 🙂

 

Edited March 23, 2021 by Alia Brookshire

[Kevin K]

@line-weight Sheesh !  Did you have to crush Alia's roof dreams to rubble?   :-). "Mr. the glass is half empty!"  :-)

That said....certainly from a construction standpoint, your comments are well founded.

[AliaJB]

@Kevin K Hey again-- I'm having a bit of trouble getting the extrude along path to look like yours. Would you mind just posting screenshots of your process? I tried extrude along path with a profile NURBS curve that angles towards the center of the roof at a 18.43 pitch, but can't seem to get it to look right. Thanks, sorry to bug you again with this project! 
Two screenshots attached: The NURBS curves I am starting with, and the extrusion I am getting. I clipped the curve into a couple pieces to help with the varying dimensions of the different parts of the roof 

[Kevin K]

@Alia Brookshire How about if I just send you my file?  Then you can see exactly what I did, settings I used, etc

and apply that to your roof? Then, if you still have questions you can ask. The file is a 2020 version.

 

SPIRAL ROOF KEV.vwx

[AliaJB]

@Kevin K Awesome! Makes sense looking at it. Thanks 🙂

[Kevin K]

@Alia Brookshire Yeah, if you double click the extrude along path, select 'profile' you will see the original shape I used for the roof profile. THAT part you will no doubt need to modify to fit your specs.  Like being 16" thick, etc, as you had mentioned a few posts ago.

[line-weight]

@Alia Brookshire one of the tricky things with EAPs is that if the "profile" is not perpendicular to the "path" you can end up with funny results. It looks a bit like that might be happening with yours? Hence the twist in the curve. There are also various options within EAP to "lock profile plane" and suchlike. Inbetween times I forget exactly what each of them does, and sometimes a bit of trial and error is necessary. Vectorworks helps you here by having hardly any documentation anywhere about exactly how EAPs work so it's all a bit of a mystery sometimes.

[Tom W.]

Convert the path to a NURBS Curve.

Place a working plane on the end.

Orientate the profile correctly in relation to the path on the working plane.

Run the command.

Enable 'Fix Profile'.