I’m trying to model a Hollow doorknob handle in 2 clamshell halves that has a 90deg turn to it. At the door it is about 2” in dia and then curves 90deg and slims down to 1 1/2” - How can I do this? Is there an extension? When I do the 90deg with the follow me tool, there is always a portion of the ‘pie’ that is left out.
It would help if you share the file. Likely you are running into SketchUp’s “tiny faces issue”. Work on the model scaled up by a factor of 1000x to avoid that. And extension may or may not be needed but it depends on the exact shape. What is your use for the handle once you have it modeled?
If you have an image of the handle would also be helpful if you share, there are always different ways to model anything on sketchup.
I’ve attached the file. It’s actually a modification of a J1772 EV Charging Plug. The easiest way to explain it was as a door knob handle.
I’m taking the manufactured part and turning the handle 90deg so that it takes up less space when plugged into and EV for charging. I have an application for it. For the internals I’m using the existing parts from the manufactured item. In the file I don’t show that it narrows down since I couldn’t make that happen. I want it to be 1.75" at the bottom. I’ll attach a jpg of the manufactured injection molded clamp shell half that I’m basing my drawing on.
Personally I would make the shape you want with follow me, then bend it with Fredo’s Radial Bend tool.
You can make it as complex as you want, this is just a basic shape.
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Thanks Box, I found Fred06 bend app, installed it and got it working for me. But I don’t understand how to neck/slim down the length to my desired 1.75”, I want it to be a gradual taper. What did you use to do that?
That’s just basic follow me, draw whatever profile you want and use a circle to make it.
It looks like @Box got you pointed in the right direction. Here are a few additional things.
First, go into Model Info>Units. Untick the box for Length Snapping. I would set Display Precision higher than what you need in the model so you can see small discrepancies and correct them if needed.
Second, use Tags correctly. Leave Untagged active at ALL times. Create and leave all edges and faces untagged. Only give tags to components and groups.
This is the result of fixing incorrect tag usage.
Third, right click on an axis line and select Reset to put the axes back in their default position so they intersect at the origin.
As for the missing faces with Follow Me, there are two issues. One is the tiny faces issue. The other is that your Follow Me path isn’t set up correctly. Follow Me needs the first segment of the path to be perpendicular to the profile. If it isn’t the profile gets projected (not rotated) to perpendicular. The extrusion also ends perpendicular to the last segment in the path. If you just draw an arc with one of the arc tools the first segment won’t be perpendicular to the path. Here’s an example. I set up a profile along the red axis. The first path is an arc drawn with the 2-Point Arc tool. You can see how the ends of the extrusion are not on axis. On the right I added a starting edge to the path that is perpendicular to the profile. I also added a segment at the end that is perpendicular to the green axis.
While this doesn’t take into account the taper you want, here’s the result of running Follow Me after scaling the model up and adding a short perpendicular segment before the arc. Follow Me starts at the origin and goes to the left. I’m also using more segments for the various arcs to make the result smoother.
Since you are working in inches, do your modeling as if inches are meters. That is, set the Model Units to Meters. Enter the dimensions directly without any conversion. This will help to avoid the tiny faces issue and also allow you to create smoother curves. If your slicer software allows you to select inches as the units for the .stl, you can export the .stl from SketchUp with the units as meters and just import it. If your slicer is like mine, it only works in millimeters. In that case, once your model is ready for printing, scale it up by a factor of 25.4 and then export as meters.
Use Box’s method of modeling the thing straight and then using Radial Bend from FredoScale to put the bend in. I don’t know if this is the sort of taper you want. I drew a Bezier curve for the outside taper down to the .8750 radius. Then Offset for the interior curve. Note that I am working centered on the origin and green axis.
I used a circle for the Follow Me path and later removed half. I prefer that for things like this because I find it easier to assess the resulting shape if I can see it all.
If you prefer to model only the half, remember you need to set your path up correctly so that the first and last segments are perpendicular to the centerline of the part. On the left is a arc drawn with an Arc tool. In the center I have a circle which I rotated so that there are vertical edges crossing the red axis. And the extrusion result on the right.
Here’s the result of bending the thing with Radial Bend. (I might want to change the shape a bit but you get the idea.)
With the bent thing as a solid component, I made a “cutter” block as another solid and used it to cut away half of the handle.
That half was copied and flipped to make the opposite half. Then the tabs and the edge details were added. Still need the screw bosses but I don’t know where you want those. A note about those tabs. They need to be fixed. They are not currently solids.
Thanks Box, I’ve followed your process and made a few iteriations, now I’m trying to incorporate the other suggestions that @DaveR has made. You guys are extremely helpful. In your example how do you get the drawing toolbar and measurement all in one bar?
WOW! You’ve given me more to chew on… I’m not sure I understand your ‘modeling as if inches are meters’ suggestion. When I change my model info units to M, my height becomes 0.02769m and in your screenshot I can see that your’s is 1.0900m, which is the inch height with m notation. I espically envy your last screenshot showing both halves with the tabs and the seam overlap. (As an FYI if you look at the picture of the inj. molded piece you’ll see a different way they handled the seam.) What do you mean about the tabs being fixed?
And you’re perfectly right about the screw bosses, that will be a challange for me.
STL files are unitless so you can model in meters and print in millimeters. Here’s a recent example I modeled in SketchUp and 3D printed. You can see the overall diameter of the gear in the model is 17 meters. The printed gear is photographed on a US quarter. This gear is probably only useful for collecting dust on a shelf but it illustrates the idea.
There’s no need to scale the model down before exporting. Just make sure Meters is selected in the export options.
As I mentioned, my slicer only works in millimeters. The U-joint in the following image was modeled based on dimensions in a textbook on technical drawing published around 1905. The dimensions were given in fractional inches. When I created the model I just used the those numbers but as meters. Then, before exporting the .stl files I scaled the model up by 2.54x. The shafts are 1 inch diameter. I scaled the model up so the shafts in the model are 25.4 meters in diameter. They then print as 25.4 millimeters in diameter.
I scaled your model up to get the dimensions shown. You can do that or you might find it makes more sense to start a new model with the units already set to Meters (and Length Snapping off).
You could model yours that way, too.
The side tabs are missing faces so they won’t be identified as solids and won’t print correctly or at all. The objects all need to be manifold or “solid” in SketchUp’s terms. To be solid every edge must be shared by exactly two faces. No fewer and no more. In the case of the side tabs the missing faces means there are edges that are supporting only one face.
Note that as far as 3D printing goes, you can do things such as leaving the tabs as solid objects separate from the handle side. The slicer will combine them. That’s useful in cases where you might want to make edits to the tabs without worrying about modifying the rest.
The nice thing is that mainly it’ll just be a case of placing the bosses (as solid components) where you want them. If you are making sure that you’ve got solid objects, you can model a sort of drill/counterbore object and use it to make the counterbored holes on the exterior for the screws. I did that with the clamps and subtracted the “drills” to get the holes and recesses.
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I’ve got the shape I want. In the screenshot, the top two straight versions are what I want, one has been split into top and bottom using cutter block. But as you can see when I Fredo radial bending, the axis angle all end up wonky.
What am I doing wrong? I’m tempted to start over again with m and 10x, but I’d still encounter most of the same problems, which is not knowing what to do… so again thanks for the help.
It looks like you’ve allow the Rotation axis to be perpendicular to a face that isn’t parallel to the ground plane. Just as with the native Rotate tool tap the Up Arrow key to lock the rotation axis around the blue direction before you start to bend the object. The protractor needs to be displayed in blue, not black.
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@DaveR YES, got it thanks
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Dave’s got you sorted but just a note on Radial Bending.
The results change depending on where you position the tool and how much of the object you choose to bend.
Four examples here show some very quick differences.
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@Box - right, I found that out by putting the bend in the same area as your first example and inside was all kinked up. By playing around I got what I think I want. It looks like a very useful tool, will have to investigate it and the other parts more. Thanks for the help.
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