Cable Tray Clearance

[Anonymous]

Anyone have some tips on creating a clearance for the cable tray system/families? I need to get a clearance to show up as we run tray throughout the model. Any ideas would be great.

Thanks.

[russellvee]

I had to do this for a BIM coordination project and it was pretty ugly. Revit doesn't have any way to modify the cable tray families but our client insisted on showing a 2" clearance for navisworks clash detection. I ended up modeling 4" cable tray, then converting it to 2" cable tray and exporting it to autocad. Then I imported the 3D autocad solid, made it transparent and raised its elevation 4" so it would sit right on top of the 4" tray. It definitely shouldn't be that complicated but that is the only thing I could get to work.

[Anonymous]

Thanks for the reply. Did you nest the transparent family in the tray family? How did you get it to work with the tray? Or was this a seperate family you just ran on top of the tray family?

[russellvee]

No, I wasn't able to do anything with the family or make the clearance "work" with the tray. After finalizing my tray layout but before exporting to navisworks I created a 3D dwg solid and imported it into Revit directly above the tray. If I made any changes to the tray I would have to repeat the export/import process.

Here is an example.

[Anonymous]

Ok, I see what you are doing. That probably wouldn't work in our case. We try and use DWG files as little as possible. I think I may end up nesting a clearance in the cable tray fittings families and just have my team run all fittings, not a system. Or just make a clearance family and have them just run that after they run the tray. It seems like the only way I can think of making it work somewhat effeciently inside of Revit. If i come up with something that works well. I will post it on here. But, I'm still up for other options.

Thanks.

[smbrennan]

In my opinion, you have 2 options:

1. Create your own cable tray family and classify it as a data device. This way you can add sub-categories for clearance and control it's visibility.
2. Use the Native Cable Tray Family, but simply adjust the height to include your required clearance.

I know #2 is not as ideal because of taging, but as a workaround to that you could make project shared parameters for cable tray & cable tray fittings to control the tagging of height. But then again, you'd have to do this for option #1 as well - but option 1 gives you a little more control.

Be sure to use my link below in my signature to provide product feedback. It's the best way to get Autodesk to see these needs we all have.

[Anonymous]

Thanks for the reply. Your #1 solution is kind of how I was leaning. Reporting the "offset" "elevation" may be an issue. The higher ups don't  seem to like the idea of drafers having to to use/pick "fittings" and not use a cable tray system. So, it looks like I may be stuck making another family just showing a clearance. And the drafters will have to run it on top of the cable tray runs. Not ideal. But, my hands may be tied. I'll probably create both options and present them as options.

[smbrennan]

No, tagging your elevation is easy: DON'T build your family off of the reference level. Create separate reference planes that are parallel to the reference level. Then associate a dimension to the bottom plane to a shared parameter (instance). Dimension between the two for your height parameter. Now that I think about it, add a 3rd for your vertical clearance. I use this method for unistrut hangers and it seems to work pretty well.

[Anonymous]

Good tip. I may steal this for my unistrut. We have been trying to get our elevations on that family to get pulled as well.

For the cable tray data family. Do you suggest using a line based family or just make a family with grabbers on each end?

[Anonymous]

Also, I believe I have read other places that doing your method to get the elevation to pull. Can end up being a little confusing for drafters. Be cause the elevation/offset (built in parameter) shown on in the properties window is not the actual elevation anymore. Is this correct?

[smbrennan]

Right now I only have one cable tray family, and that's for basket tray. I'm not using a line-based family. Performance is lost when you have to drag it, but I think that's more because of the rungs being arrayed in the family.

Yes, it can get confusing. They will need to know to keep the offset value to 0 for this family. Until that parameter becomes available for tagging, we just have to make with what we have. Again, provide feedback for that. We're not the only one's who have asked for it. Power in numbers, right?

[Anonymous · Accepted solution]

So, what I ended up doing was making a clearance, line based family for the straight runs of tray. For the appropriate sizes of tray we use. And running that after the system of tray is ran, at the necessary eleveation. Then in all the tray fitting families. I built in a clearance that flexed with the size of the tray. All in all, its fairly seemless and quick.

[kwbolger]

This issue is becoming more and more of a problem for us with more and more projects going to Navis for coordination. We have used a line based "clearance" family with parametric height and width and hosted it to the top of the cable tray and it has worked ok but it is a headache to essentially draw your whole layout twice and then whenever there are changes to the tray layout we have to remember to go back and turn on the clearance and update it as well. There are also issues associated with fittings the clearance family always show up as a clash on itself if you don't stop and start it at Ts or Xs and then when there is a change in size of the tray we have to stop and start with the next type that corresponds to the next size of tray. Is there a good reason that Autodesk hasn't added a function similar to pipe insulation clearance to deal with this. Or better yet allow users to edit the cable tray family to add our own clearance families to the cable tray as needed? I assume the reason has to do with the fact that it automatically adds the fittings but if there is a way they worked this out for piping and ductwork insulation I have to imagine replicating that to the cable should not be that difficult.

[GAB.]

Also dredging up this thread. I have a clearance family that I could adapt to the fittings - annoying but doable. But since you can't edit the straight runs at all, there's pretty much nothing you can do other than what's already been suggested on this thread.

I had another idea, but since you can't edit cable tray material and it's not technically a system, that's also out the window. PS vote for @fabiosato's idea for cable tray material. 

[pamela_fisher]

Really bummed to find there has been basically no movement on this issue for *checks notes* nearly 10 years.