Loft Massing issues in Revit

[dimitris.katsarelis]

Hello all,

I have an issue regarding the mass blend mode.

I want to produce a solid (created in Rhino) as shown below:

but when I'm using blend (or sweep blend) I'm getting this result:

I've seen that this issue has been raised before but so far I have found no solution to smooth the surfaces.

Any ideas?

Thanks in advance

[RDAOU]

@dimitris.katsarelis 

It depends on the purpose of your exercise...if it is to check whether Revit massing environment, using the standard OOTB tools, replicate something which you can create in Rihno or any other application, the answer is no. Certain forms require an entirely different workflow to create them and in most cases it would be a far longer road to take than the shortcuts you might find in other software.

Considering time on projects is precious, trial and error or experimentation or taking something already modeled in a different software and remodeling in Revit are not feasible options. We

• either model such forms using Dynamo (similar to how you would use Rhino and Grasshopper together) if it is from scratch
• or simply bring them in from whichever software they were modeled in and use them in Revit as direct shapes.

[dimitris.katsarelis]

@RDAOU Thank you very much for your quick reply.

I wouldn't mind using Dynamo in order to create it. I was just wondering if the script is too complicated to do this as I'm a novice in Dynamo..

Do you have something in mind?

My issue with bringing them from other softwares is that small differences in the shapes due to design development mean that we have to go back and forth everytime to adjust them.

[RDAOU]

@dimitris.katsarelis 

It is not that complicated no. However, you should note that the shape in such case is being created in Dynamo not in Revit. It is placed in Revit (most cases) as a direct shape...ie: not much difference than having it modeled in Rhino or Formit and bring it in. So the back and forth is part of the process

I would put an example for you but I don't have access to Revit atm... You can check on Dynamobim.org forums or Primer I am pretty sure you will find lots of examples or even graphs from people trying to do the same

[dimitris.katsarelis]

@RDAOU 

Great, I'll give it a go.

I just had an idea.

Do you think it could be done with an adaptive family?

[RDAOU]

@dimitris.katsarelis 

You will also not be able to loft these forms in adaptive family environment ... the principle of modeling such forms kinda differs in Revit ... see below example (that was for another similar question from another forum member but the principle is the same)

[syman2000 · Accepted solution]

Revit adaptive can be frustrating to understand. Typically if you are using loft, Revit treat it as loft from 1 line to another. If you have base that has 8 lines and top only have 1 line, then you will get weird lofting behavior.

To keep it smooth like you have in rhino, you have to split the top to the same 8 segments as below.

When you loft, it will smooth the surface.

[RDAOU]

That is exactly the trial and error I was talking about...splitting wont really help even if user gets to nails combination that works after 2 or 3 trials...once the shape is slightly above average it is impossible to get rid of the edges or smooth them...and when it come to a design modification starts the nightmare. 

Lofting is not a Revit thing

     

[syman2000]

Yea this is disadvantage of Revit adaptive. It is very rigid and prone to breakage.

[dimitris.katsarelis]

Thank you guys a lot for your replies. That was really helpfull.

Even with the blend mode, if you split the top line to the according number of the bottom lines, as @syman2000  suggested, you get it smooth.

But indeed, with the design modification it takes really long time to make them, we already have 8 different shapes of this kind. The frustration keeps with the fact that I have to make them twice, as I need a void shape for cutting through floors..

[RDAOU]

I wouldn't call it a disadvantage ... Just each software has its ways and one way or the other one can model the same in all software. But between doing that in Revit and say going back and forth between formit or inventor where such blends/lofts are more or less a couple of clicks...I vote for sure go with the latter