Custom Pipe Elbow Family Changes Pipe Slope Automatically

[r63501736]

ite family consisting of two 45-degree elbows, which is used at the base of sewer stacks. To insert this family, I first connect the stack to the second pipe using a single elbow, and then I replace it with this composite family. However, when making the replacement, the pipe slope changes. For example, the slope originally set to 1% changes to 1.5% (please see the video).

Additionally, sometimes it even changes the slope of the vertical pipe (stack) to unrealistic values, for exemple (150000%)

I would like to know if anyone has faced a similar situation and how they managed to resolve it.

Thank you!

[iainsavage]

Not sure why it would do that but I don't understand your workflow - why don't you just include the elbow in the pipe's routing preferences and promote it to the top of the list. It will insert just the same as any other elbow.

There are some other issues though.

I think you want to relocate the connectors as shown by the arrows below

When viewed in hidden line mode most of the fitting is invisible (masked by something in the family?)

[r63501736]

Thank you for your response!

I understand your suggestion about including the elbow in the pipe's routing preferences and promoting it to the top of the list. However, this specific configuration of two 45-degree bends forming a 90-degree connection is not the most commonly used in my projects. Therefore, it wouldn't be productive to have it at the top of the routing preferences list.

Even when the elbow is included in the routing preferences, it still changes the slope. This is the core issue I'm trying to address.

Regarding your comment about the positioning of the connectors, you are correct. I need to reallocate the connectors, but I left them in their current positions while trying to solve the slope issue.

When I insert the custom family, the slope of the vertical pipe (stack) sometimes changes to an unrealistic value, as shown in the attached image.

Do you have any further suggestions on how to prevent the slope from changing automatically when using this custom family? Any additional insights would be greatly appreciated.

Thank you again for your help!

[iainsavage]

" this specific configuration of two 45-degree bends forming a 90-degree connection is not the most commonly used in my projects. Therefore, it wouldn't be productive to have it at the top of the routing preferences list."

When designing drainage systems there are such a variety of bends and branches used in the average project that the best workflow that I could find was to include everything that I needed in the routing preferences and then be regularly promoting/demoting fittings as required depending on which part of the system I was modelling. Swapping fittings doesn't always work because the pipe alignment changes e.g. swapping a swept branch for a 45 degree branch.

"Do you have any further suggestions on how to prevent the slope from changing automatically when using this custom family?"

I think it could be related to you swapping out the fitting and the dimensions of the fitting and location of the pipe ends being different from the standard bend so Revit tries to flex the pipes to suit the change in geometry (but that's just a guess).

I also noticed that in the family the bend angle is always 90 degrees and does not flex for different pipe angles - it relies on the "allow slope adjustments" option  to allow pipes to have slope - not sure if this has any impact on retention of pipe slope value though.

This bend flexes to the pipe angle:

When I swap this fitting for yours I get this warning which usually means that there are alignment differences and it won't actually let me complete the swap, I can only cancel the operation:

But if I swap it for another bend family it works okay and retains the bend angle and pipe slope:

So I would conclude that its probably because the angle between connectors in your family is not controlled by the pipe angles.

@fabiosato is better at interpreting problems with families than I am though so he might have better advice.

[fabiosato]

Hello,

This is quite a complex family to create.

You have to determine the origin of each elbow family, and they must flex at half the angle of the host family.

It would be best if you calculated the position of the origin for each nested family.