Basic Question for Imported Parts
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Hello,
I am just starting with SketchUp and I have a basic (I hope) question.
I have an assembly of a small engine that was made in Alibre. When I export it to Sketch Up, some of the engine screws are round, while others are hexagon.
The screws are 4-40 button head which should be round.
While in SketchUp, is there a way to modify this?
Thank you in advance. -
Have you got a pic of the problem? im feeling a bit slow today.
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Yeah, some pics (or even the screw models) would be nice. Maybe they just don't come through softened.
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Thanks for the quick reply.
Sorry for the quality. Its late and I don’t know how to use the program efficiently.
Again, only the screws are like this. The rest of the model has the correct radius on the correct parts.
Thank you.
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Well, it seems that the screws are based on a too low poly circle. All round geometry is made up of segments in SU but when they are softened, they look round. Reducing poly count can ease your model but extreme reduction results in such look.
Now it all depends on the workflow you used in Alibre to define the circles your screws are based on - it seems that it is only a six sided circle (the default in SU would be 24).
See the example below: it was produced in SU on a 6 sided circle:

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Thank you again for the reply.
I have so far done the following to try and fix this problem.- Drew up another 4-40 screw and inserted it into the model.
- Had a friend draw up the screw in SW and send it to me.
- In SU. I have gone to Window/Soften Edges and tried different settings.
Nothing has worked so far.
I am trying to render this in Kerkythea, but this has stopped me cold.
The 4-40 button head screw is .214 in diameter, so I tried a smaller screw and it shows up correctly. So far, everything is showing up correctly but these 4-40 screws. I am totally lost as what to do at this point. I have probably spent at least 8 hours on this one problem. (trying different settings and looking up any possible answers on the internet)
The model by itself has 15 sides (head diameter) when I insert it into SU by itself.
I have included the model.
Could someone please look at this?
Any suggestions would greatly be appreciated.
Thank You
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Well, a 15 sided, softened screw head quite low poly if you want to render close-ups in KT. People even add segments to the 24 sided circles rather than make it lower poly actually (to have a nice render, you may even want to double the 24 segments).
Another thing; the model is qzuite a mess (don't take it wrong though). Turn on hidden geometry and see that the screw itself is made up of two sides that are not connected (i.e. you cannot soften that edge). This does not seem to be a problem though since it won't be shown I guess but generally it can cause "light leaks" in Kerky.
Still with hidden geometry turned on, you can see a bunch of lines that are not needed on the body of the screw but these are due to triangulation that Alibre probably uses and the Kerkythea exporter would triangulate these faces anyway so just leave them there for now.
An even worse problem is on the top of the head where that hexagonal hole is. There are a bunch of lines and overlapping faces there wich will definitely cause problems during rendering. To avoid this you should use a segment number for the outside circle that can be divided by 6 in order to achieve a nicer intersection somehow.
I think you could (or at least should be able to) create this screw in a couple of minutes in SU instead of suffering with a CAD program plus importing isues really.
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Thank you for your comments.
I have a couple more questions if I may ask please.
How do I turn on hidden geometry?
Where is the option for the poly circle count?
I do have the free version of SketchUp. I have looked and I cannot find these options.
Thank you. -
View (manu) > Hidden geometry.
When you create a circle and immediately afterwards type a number followed by a letter s (like 48s) and hit enter, it will have that poly count.
Also, until you do something to the circle (say extrude it), you can right click on the edge and choose "entity info" where you can still change the segment count (both methods work for the polygons, too).The free version is only limited in its export functions mainly and all modelling tools are equally available with the pro version.
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