How to make a groin vault?

[1090291004350551]

Hello everyone,

In my current project, a client asks for a groin vault, something like that. 
I've looked through the forum but I can't find anything about this.

 

How is it possible to do with Chief? 

 I would be very grateful for a video.

Thanks in advance 

[Greg_NY61]

You can use curved ceilings as solver did, I tweaked the dome in Sketchup and imported as a symbol

 

 

[Alaskan_Son]

Here's a 3 part video series I made on the subject a little while back.  I would really recommend watching all 3 even if the first one solves your problem.  There's some good information in there....

 

[1090291004350551]

Quote

Here's a 3 part video series I made on the subject a little while back. 

Thank you! I thought about just doing it in Sketchup but I will try your way.

[DzinEye]

On 5/18/2020 at 10:21 AM, Alaskan_Son said:

Here's a 3 part video series I made on the subject a little while back.  I would really recommend watching all 3 even if the first one solves your problem.  There's some good information in there....

Never had opportunity to do a groin vault before, but was fascinated after watching your video on the method for forming one over a rectangular area.  Had to try it.
Did you develop this method for building it?  Ingenious way to get those compound curved joints.  
In playing around, I accidentally discovered something which I wonder if you ran across in your pursuit of this solution.  I had run a curved ceiling plane in both directions across the room so they overlapped through each other.  Then I had changed the curve of one so it was a fraction lower than the other at the apex.  In messing around with the Use Room Ceiling Finish checkbox of those two planes I had stumbled on a situation where the ceilings automatically cleaned themselves up to show just the lower parts of the vault correctly.  Now trying it again I can only get 3 of the sides to clean up... but it seems like there's something to which arched ceiling is built first and which is set to be lower than the other and which is set to Use Room Ceiling Finish or not.  Will continue to try and sort it out, but thought you may have some experience or thoughts on this.  Would sure be a time saver if it worked reliably...and anybody really needed to model a lot of groin vaults.

[mtldesigns]

I'm sorry that this is not related to your question.. but that is the most unique user ID (1090291004350551) I have ever saw... just sayin!

[Chrisb222]

On 5/18/2020 at 1:21 PM, Alaskan_Son said:

Here's a 3 part video series I made on the subject a little while back.

 

Michael, great videos, thanks. I tried rectangle method four times last night using my template with no luck. This morning I thought, there must be a problem in my template (which has been true before with other things), so I tried it with the CA Residential Template, still no luck. Then, noticing that your videos were produced in X10, I tried it in X10, and had no problem.

 

Something is happening in X12 on my end, that when the two planes are both made into triangles the corner where they meet gets screwed up (see pic). The corner is fine when they're rectangles, and after making one plane a triangle. It happens only after they're both made into triangles.

 

I wanted to see if this happens in X12 with you too, or tell me what I did wrong. Test file attached.

 

 

Groin Vault Test X12.plan

[DzinEye]

2 hours ago, Chrisb222 said:

Something is happening in X12 on my end, that when the two planes are both made into triangles the corner where they meet gets screwed up (see pic). The corner is fine when they're rectangles, and after making one plane a triangle. It happens only after they're both made into triangles.

 

I wanted to see if this happens in X12 with you too, or tell me what I did wrong. Test file attached.

Didn't look at your test plan yet Chris, but I did it using X12 and it worked fine for me.  It is fidgety though...  I just redid it really quick and got a strange artifact you'll see in my pic. I think because I rushed the process of making the compound curve.

[Chrisb222]

1 hour ago, DzinEye said:

Didn't look at your test plan yet Chris, but I did it using X12 and it worked fine for me.  It is fidgety though...  I just redid it really quick and got a strange artifact you'll see in my pic. I think because I rushed the process of making the compound curve.

 

Oddly, when I add any random corner point to the common edge of either ceiling plane, the corner instantly falls into place correctly...

 

[Alaskan_Son]

21 hours ago, DzinEye said:

Did you develop this method for building it?

 

Yes sir.  I did.

 

21 hours ago, DzinEye said:

In playing around, I accidentally discovered something which I wonder if you ran across in your pursuit of this solution.

 

21 hours ago, DzinEye said:

In messing around with the Use Room Ceiling Finish checkbox of those two planes I had stumbled on a situation where the ceilings automatically cleaned themselves up to show just the lower parts of the vault correctly.

 

Chief is a little finicky in this regard, but yes, you can get the ceiling planes to clean up decently well in 3D but...

-It can be very difficult to accomplish for even a single edge.

-It becomes exponentially more difficult to accomplish for multiple edges.

-Perhaps most importantly, it requires shifting edges and moving planes so that the results become quite inaccurate in other views--particularly Plan View. 

 

It's just not worth even going down that road in my opinion.

[Alaskan_Son]

4 hours ago, Chrisb222 said:

I wanted to see if this happens in X12 with you too, or tell me what I did wrong. Test file attached. 

 

The height/radius on one of your roof planes isn't actually correct, but that's not what's causing your problem.  I'm not 100% sure, but I think what you're seeing is just the result of some hardcoded facet angle limitations.  I wouldn't worry too much about how it looks right now.  I think if you keep going through the process, you should still end up with the desired results.  Having said that, you may need to tweak things a little for your specific plan sometimes anyway.  For example:

 

I've found that you may need to shift the start and end points of your manually drawn valley so that they snap right to the corner points (wall and peak) instead of to the line created by your CAD Detail From View.  In addition, your ceiling planes could be such that they don't actually create any usable linework at the valley prior to that CAD Detail From View Step.  In those cases, try temporarily changing the material being used for your ceiling to get some additional snap points.  In fact, this may be preferable anyway since it results in a nice uniform snap interval...