Ghost Geometry

I am modeling using S.U. and I am being plagued by UOE (Unidentified Operator Error).
This problem is becoming more and more prevalent, and will be difficult to understand if you haven’t had the misfortune to experience it. I don’t know how to call it, but I call it a “PHANTOM GEOMETRY”.
In the progress of building a model, I am finding geometry that I didn’t put in. It is a shadow geometry in that it has typically no geometric (line) boundary. I have seen these ghost geometries with a single-line boundary. The only way that I can rid my model of this anomaly is to “select” and “delete”. But the truth is that it’s like a cancer and can easily reappear. This is so invasive that I find it necessary to abandon the model, save it to documents and delete it from the document file. If I delete it in SU, it just reappears as if it is lurking in the background. The strange thing is that it seems to be happening with increasing regularity. I am trying to concentrate on taking care to insure that each line is properly adjoined to any previous geometry, but the problem persists.[WHL South Coin Drawer Wall-WIP-](https://WHL South Coin Drawer Wall-WIP-)

I am using SU 2017 make

You need to attach the model properly.

Please remind me as to how I post it properly

You can drag and drop the .skp file straight into the reply window.
Or use the 8th icon from the left that looks like an up arrow at the top of the message box to load it that way.

WHL South Coin Drawer Wall-WIP-.skp (623.2 KB)

It looks like your issue is down to the native stickiness of geometry in sketchup. You need to use groups and components to stop all the edges dragging things around. Every time you move something it tears the nearby faces and creates all those hidden edges. If you go to View/Hidden geometry and turn it on you will see all the extra edges being created.

You need to learn about groups and components.
A group is a collection of edges and faces that have been wrapped up in a container so they don’t stick to other geometry.
A Component is a special type of Group whose copies are linked together. Edit one edit them all.

So each of your Logs should be either a group or a component, make one then copy array it to make all the rest and so on.

You are also working at a very small scale which can cause all sorts of issues, try working at real world sizes. The model can be reduced later for printing etc.

It’s also important to keep on top of face orientation, the white faces are the front and the gray are the back, so on a correctly made log you should see no gray unless you go inside it.

Also, go to Window/Model Info/Units and untick Enable length snapping. It also causes tiny errors and is probably why many of your dimensions contain a ~
It would be best to open your blank template and adjust that and resave the template so it is off for all models from now on.

Here’s a quick demo using components of making some log walls.
I start with one end piece, then make full logs from it without losing the original.

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This demo goes by so quickly that it is hard to follow. The toolbox that is shown has a feature that I’ve not seen … the X-symbol with the circle around it doesn’t show up in my toolbar. Also the “distance” and “measurements” heading is another feature that I’m not familiar with.
Another question is the size of the modeling that I’m doing. I typically establish a scale size that I can use to develop the required model size. Then I zoom in to enlarge the display to the point that I can work with it and the scale is already set to what is a “real-world scale”. If, at the time of 3D printing I can scale up or down if required.
When I first started using SU, I’m sure that I established a “template”, but I’ve not visited it since. What "adjustments " should be made?

Clay it is very late for me so I will be going to bed after posting this.
You would do well to spend some time at The Campus a very useful bunch of video tutorials.

The Demo is in real time so it is hard for me to be slower but it does show everything I am doing.
The x with the red circle is nothing more than the delete icon found on the ‘Standard’ toolbar. It is a visual version of hitting the delete key.
The distance and measurements are by default seen in the bottom right corner of the screen, I have moved them just for the benefit of the gif.

Too late to really address your template issues, someone else may fill you in.

(https://WHL South Coin Drawer Wall-WIP-).
The link above shows the basic geometry of the South wall of the house (WHL) that I’m trying to model using your method of building the model. The house walls will be printed separately and assembled post printing just as a model ship or airplane would be assembled. The East and West Walls, then, will be modeled separately…the protrusions of the E & W walls through the South Wall, should be part of the South Wall model. Additionally, at the middle of the S wall, will be a third “Log” protrusion at the midpoint of the wall to make it appear as if there is another wall perpendicular to the south wall. The interior portion of the S wall will not be “LOGS” but will be flat and 3/16" inset to the wall interior ( the interior of the house will not be seen, and therefore be just a flat wall. On the centerline of the S wall exterior, I had planned on including the third protrusion hence the beveled exterior of the log face that I had expected to insert the log extrusion.
The goal remains in all of this is to achieve a “SOLID” (aka “Shiny” in the SOLID INSPECTOR) so that it can be printed on a 3D printer.
One stumbling block that I am having is how to make a Selected component “UNIQUE” with the goal of
extruding the interior segment of the S wall to the centerline.
This is all kind of confusing, I know, but , as you can tell, I’ve not been shown the correct way of producing solid geometries…hence, my call for help.WHL South Coin Drawer Wall-WIP-.skp (772.1 KB)

One thing you need to look at is the shape of your logs, creating them as circles will make them difficult to form into stacks that are solid, and can be printed. The problem is the points come together which will stop them being solids, they become zero thickness points. The real logs are generally flattened on the top and bottom too, so it make sense to do it here.
Notice in this gif how the two circles only form a group, but the flattened ones form a Solid Group and you can see the extra ‘meat’ in the middle.

Flat logs

Here I show making one log as a component, then copy from that and Make Unique. This lets me array the unique components and modify them without altering the original. Then use Outershell to form that into one printable solid.

Solid group


Round here where I am now, they used to build hay storage with round logs with a gap between, to enable the hay to dry.
In houses for living in, the approximate round log profile looks like this (the groove is formed with an axe):

The groove enables flax or moss or some other material to be placed there to make the wall tight.
Round logs used to be considered archaic so in more cultured uses the sides were flattened with an axe:

A new log house will shrink when the logs dry. If the logs are placed flat on each other this will cause gaps. The groove enables also the weight of the structure to press the “tongues” tight.


I bow to your superior knowledge on the subject of log cabins @Anssi , my only real experience with them up close and personal was some years back when in the wilds of Finland. A weekend of hunting with some local work colleagues. I’m still amazed nobody was shot and my abiding memory is of having to drink Terva, god awful stuff. Had to wash it down with liberal quantities of Koskenkorva. Fortunately no animals were harmed in the making of this adventure.

Back on topic, while your design is correct it doesn’t lend itself well to 3d printing. Must admit I only did a quick image search and determined that the logs weren’t just sitting one on top the other without any trimming, so I flattened them.

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I would either print individual logs or forget about the internal structure and print a wall with the outward shape of the desired look. Round logs could be combined with the Union or Outer Shell tool.

Only if they are overlapped, which is what I was hoping to avoid.
By giving them a flat they will stack and combine easily.

Oh, WOW! That makes so much sense! Thank you for that tip of flattening the “logs”. I didn’t realize that the zero-thickness points is the center of my problems.
Another thing that I haven’t learned is how to “make unique”. Using the SELECT tool is another weak spot in my approach to modeling. I see that sometimes you drag the select left-to right forming a solid window, and then right to left forming a dashed window. I’m not understanding the difference and the real purpose of each method of selection. I’ve been visiting CAMPUS to try to fix my methodology but haven’t found the select tools yet.
I got a kick out of @Anssi’s approach to “real logs”. There isn’t a tool for CHINKING… :crazy_face:

Make unique , right click on a component and choose “Make unique” from the context menu

A left-to-right selection window selects (or de-selects) all entities which are fully enclosed by the rubber-band rectangle. A right-to-left selection selects (or de-selects) all entities which are partially or fully within the rubber-band rectangle. Both are very handy features of SketchUp.

:+1: :ok_hand: :clap:

:+1: Thank You !!

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