Bending and radial copying

Hi all, have not been here in almost a year, hope everyone has been safe during these unique times. I have dusted off a house project I was working on and have forgotten everything I had learned here… :roll_eyes: Actually went back and reread all my earlier posts as a refresher.

So I am posting two questions as they lead to the same design objective. I am trying to model a curved trench drain. The first file (trench drain section.skp) I found in the 3D warehouse but have not been able to bend it using Fredo, CFL Bending tool or Trubend. As a test I made some simple ‘bars’ and bent them successfully though. Also when bending an object, I see that the angle of bend is shown, but can one set the radius or diameter? If not how does one make an object fit a specific location?

The second file (curved trench drain.skp) shows a partially completed trench drain in my model. I tried to make one by using a component from the 3d warehouse, but have been unsuccesful in copying it with the actual voids (where the water would drain) I just get the outline on the face. I actually did partially copy it successfully a couple of times, but was unable to repeat it, and can’t recall what my workflow order was. In reality a trench drain of this length would not be continuous (the radius is 13’), but would probably be in 2’ sections and I would prefer the model show that, but not completely necessary as it would be hardly noticeable. This trench drain is at the exterior of a cylindrical building shape where it meets an outdoor patio on both sides of the cylinder. (Some of you SU sages may recall my queries regarding perforated windows and curved railings, etc. last May). I made the drain insert that I copied from the 3DW component red so it is visible as it is quite small.

Also I have been struggling with changing axes, both in an individual component and in the whole model once I geo-located it, but I’ll save that for a separate post. More questions to follow.
Thanks in advance

trench drain grate.skp (691.3 KB)
Curved trench drain.skp (1.5 MB)

Couple of problems goin on here. The reason you are having trouble bending the first file is because the drain component you are working with has it’s axis set strangely, with the green pointing up. With the component closed, right click on the component and select Change Axis. Reset the axis the way I have, with the blue up and the red in the long direction. With this done I was able to bend it using Truebend. The others should work too.

The second file shows a very clear misunderstanding of both Layers (Tags) and groups and components. Your holes are not appearing in the face of the drain because:

  • They are in different contexts. The “holes” are in their own component, and the surface you are trying to cut is in it’s own group. Geometry must be in the same context to interact. Any geometry that is “inside” of a container like a group or component cannot “touch” anything else. Normally you could explode both of these so they could interact. Or, Cut one of them such as the holes and paste in place it inside the container of the other, then explode it. The solution would be that you need to get the raw geometry of these two things to touch. Except…

  • You are using Tags/Layers wrong. You have put the raw geometry of these two objects on separate tags which is further confusing the situation. All raw geometry MUST remain on layer 0! (untagged). The active layer MUST always be layer 0. Only groups and components should be assigned to layers. Make and object, make it into a group or component, then assign that group or component to a layer, in that order. Having raw geometry assigned to layers invites all kinds of confusion and model destroying unintended interaction.

Incidentally , I would turn off length snapping in Model Info>Units, it can lead to inaccuracies.

Is this scale correct, the drain holes are 1/4" wide?

It would probably be best to start over. With the drain holes modeled in the same context as the surface it’s simple to select one set of geometry, copy rotate it, and enter a multiplier.


Riley, thanks for that, much appreciated. I didn’t even think to check the axes within the component. Regarding the layers in the second file, I extracted just these few items out of a larger model with the layers they were assigned to. I did try to isolate the drain as a separate layer but not to Layer 0. But yes, I need to understand the aspects of raw geometry more thoroughly, how to explode items, assign groups and proper layer organization. The spacing in the grates depends on the manufacturer, but I would imagine it would be in the range of 1/4"-1/2". Not sure how realistic the component from 3DW is, but it will suffice for these purposes.

It’s not uncommon, with warehouse items or just from moving things around to get component axis that differ from the global axis. It’s often a good thing actually as when editing inside a component all moves are relative to the component no matter how it is oriented. But for the bending extensions, the scripts can be very specific about which axis they are set up to bend on.

Exploding an item is a potential source of confusion. If a group or component is assigned to a layer then later exploded the raw geometry that was inside that container inherits the layer assignment that the group had, many have asked for this to be changed. I needs to be manually reassigned to layer 0, or there are many extensions that will check for any raw geometry on any layer and move it to layer 0.

There is some good info on groups, components and layers (tags) here:

I will go through those tutorials, thanks or the link. Is there any extension or method to check imported components for axes orientation, or does it have to be done manually?

Another quick question, I geo-located my model on a site and then had to “nudge” it into position in the actual city block, now the axes is not in the center of the model where it was originally. I have tried to reset it, but it seems to revert back.

Note: I think I figured it out. I just had to select all then save. Seems to be working now.