How to sheath a reciprocal roof — twisted plane

I finally figured out how to lay out reciprocal roof rafter logs.

Now, I’m trying to sheath it. :frowning:

The problem is that adjacent logs are not co-planar. Simply tracing a trapezoid between adjacent logs doesn’t fill in like it would co-planar.

The real thing will be sheathed in 2x6 tongue-and-groove. So I thought I would try to assemble individual 2x6s on the frame, starting at the lower ends. But I can’t seem to make that work.

I tried drawing a parallelogram that I could extrude. But it won’t fill in to make a face.

I thought of laying a line down across the ends, making a 1.75x5.75 rectangle on one end, and using “follow me” to draw the 2x6, but it won’t draw a rectangle on a slope — it insists on squaring it up with the RGB axes.

The pole is a component. So I tried “edit component” and was able to make a rectangle that was co-planar to the pole and extrude it, but that isn’t really what I want, either! I don’t see any way to “follow me” while editing a component.

If you have any advice for me, I’m all ears!

You can get the model at: Trimble Connect Web

Thanks!

That link may not work. Here is the URL Trimble Connect told me to use: SketchUp

use the other rectangle tool, the oriented one. it allows you to draw a non orthogonal (to the axes) rectangle, also non flat.

that, or temporary relocate the axes in a place that suits you.

well, no, both links are viewing links. first requires access, second doesn’t :wink: but sill, a viewing link

Do you need the level of detail of each board modeled? Can you just make the planes and thicken them?

If you do need / want each board model it flat on the ground and carefully place it where it goes. You will likely need to split the difference in alignment as you can’t ‘twist’ a real board into place… (but you can, if you steam bend each piece…)

Depending on how you built the roof sections you can hopefully rotate / copy the boards from one section to the next.

You could also cut backing angles on the round logs, treating them like hips. The last reciprocal roof I did was done like this (but it was square timber, not round).

Okay. I managed to sheath the roof. Sort of!

I created the reciprocal log rafters using radial step and repeat, and each of them is a component.

I then selected one log and did “Edit Component”. I then created 1.5" x 5.5" in that component, row after row, to sheath the rafters.

But the rafters are not co-planar, plus they overhang each other. So now I have some cleanup to do.

There are 20 log rafters, and 83 lengths of 2x6. I need to trim the intersection of each, and I need to periodically change the angle that the 2x6s lay against the next rafter, as it steadily increases as I go from bottom to top. I don’t want to explode everything and have 3,320 edits to do!

So ideally, I’d like to trim and adjust the 2x6 sheathing by editing the component, which should then propagate to the other 19 log rafter components.

All the searching I’ve done for trimming intersecting models require selecting both pieces. But how can I do that when it is a component intersecting another copy of itself?

Am I missing something obvious here?

Thanks for any insight offered!

Did you make each piece of sheathing a group or component?

If not, and you just started drawing inside of the log component you are in for a world of misery.

Ideally the log is a component, then the roof is another component (made up of individual components of 2x, or just one big mass).

Then you Rotate+Copy them around just like you did with the log rafters.

Make a dummy cutting block group to use as the mitering mass and use the solid tools to trim the roof boards? It can be larger than it needs and only the face of the miter or cut needs to be in the correct position.

It’s also possible to draw lines that snap to intersections of faces or edges that belong to different groups/components that are not the one you’re curently working on. Just need to disable “Hide Similar Components” in View > Component Edit. But a solid trim operation would work as long as you make a trim group you intend to delete.

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Each 2x6 in the sheathing is a group.

Each log rafter — and it’s attached sheathing — is a component.

My understanding of the difference is that components are all the same. That’s why I used it for the logs, so I could sheath 20 time faster. But I knew I’d be modifying the sheathing, so I made them groups.

But you have multiple sections that will theoretically all be the same… so if you have to change something - you will need to edit all those groups. I work with 99% components… in my video the 2x are components - I go through and make them unique (shortcut) before I start cutting. If I rotate / copy / mirror this around a structure that is symmetrical or circular I would be able to quickly update them all…

I’d like to try this approach.

I do have a tangent line on the top of the round logs. I could extrude that, I guess.

I’ll see if YouselessTube has any hints on such a process.

Cool!

I don’t see any menu picks, though. How did you get to view the boards inside your “cutting solid”?

I’ll have to play with that a bit, I guess.

They are not inside of anything - the big block is a group, the boards are components. I click through them and make them unique (with a keystroke) before I start cutting.

I used the solid tools to cut them away. I use a plugin (with a keystroke) to do it but the native solid tools will work just fine.

If you are talking about seeing the dashed lines? Those are back edges. Press K.