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Best Of
Re: Best approach for complex surface shape - Loft/Sweep/Bridging Curve/ other?
@S1mon @jelte_steur_info
thank you both for the really good feedback. I was able to (after quite a bit more hours of work) a workable copy. However, I am going to review your sketch Jelte and see how you did it.
I am having issues understanding the sketches not being constrained. I was under the impression that once the shape snaps are used, and the sketch enclosed, or finished, it is constrained. I must be mis-understanding how to lock its contents in.
nonetheless, thank you both greatly!
Re: Best approach for complex surface shape - Loft/Sweep/Bridging Curve/ other?
I think something along these lines is how the part is built up.
In general: please make sure sketches (like sketch 7) are fully constrained. the lack of tangency/concentricity etc is causing downstream issues quite quickly:
https://cad.onshape.com/documents/ccb37699191c84712fb79624/w/823c67f8bc41e015beb37e33/e/23b5ff33b5e667de837a2c93
Re: Best approach for complex surface shape - Loft/Sweep/Bridging Curve/ other?
This is a fairly complex set of features to model accurately. In general, you want to break down the shapes into surfaces with similar curvature and work from larger to smaller surfaces. It doesn't look like much in the more difficult area has a constant wall. You'll likely need to model the core and cavity sides somewhat independently.
I see a bigger transition surface, with some flanges on the sides that have some complex transitions at the ends. The core side has a conical surface coming off the round mounting feature, and then it has a large transition to the flat flange. The conical surface could be a partial revolve or semi-circular sweep. Next I would do some lofts or boundary surfaces for the major surfaces, and then work my way through the smaller more detailed bits.
Do you have multiples of this part that you could scrap one or two and cut some sections on a band saw? Can you do a 3D scan with an iOS device or a dedicated part scanner? Can you take some careful orthogonal photos with a really long lens to reduce parallax? Any of these methods would help give you more ground truth to start from. Calipers are only going to get you so far with shapes like these.
I noticed that a lot of your sketches are unconstrained. I would be careful with that, as you can easily end up with weird issues if you edit something early in the model and things aren't fully constrained or intentional.
S1mon
Re: how do I start my first sketch. I can't find a build plate, or grid anywhere. I'm on the free
Hit create/document in the top left. Hit the sketch button and do as it says.. Pick a plane.. Away you go!
Have you tried the learning center, maybe the new to onshape resources?
Re: Custom Feature: Loft Fillet
Pushing another update. I took your suggestion and implemented the change where Magnitude control the start magnitude of each Bridging curve side. That took like 10 minutes to do.
And THEN, I found another bug related when there's only 1 guide curve available and turn on Make Bridging Curve 1, which took the the better part of an hour to figure out. The joys of programming… This reminds me why I'm not a real developer.
Anyway, thanks for all the feedback and really diving in deep! I figured it won't be many of us that use this feature, but the ones who do will get a lot of use out of us (provided it works properly).
Edit1: Grrr… Technical difficulties. Now it's borked for something else. Please hold…
Edit2: I fixed the bug. We're back up and running now.
ry_gb
Re: Custom Feature: Query Variable+
@Derek_Van_Allen_BD there is also qInFrontOfPlane, and using intersection query of 2 such queries for plane-offset/2 and -plane +offset/2 there can be made a query for entities within +-offset/2 from plane - a tolerant version of qIntersectPlane
Konst_Sh
Re: Custom Feature: Loft Fillet
Another thing I forgot to mention earlier, using the radius of the sweep is a little out of line with the width control in other tools. Technically, width and diameter are different, but I would be tempted to switch the parameter to the diameter instead of radius in order to get more similar results with the same number to the width control in the fillet and face blend features.
S1mon
Re: Custom Feature: Loft Fillet
I have an update. Here's the list of changes:
- support for g2 and g3 for loft profiles, guide curves, and bridging curves
- on bridging curves, Edit Control Points is set to false and the control points are set to 1 for the sake of simplicity
- replaced "fillet radius" with "blend diameter"
- fixed a bug where merge surfaces wouldn't return a solid
- rearranged some of the ui for clarity
- if both bridging curve options are selected, guide curve tangency is disabled
- Make Loft and Merge surfaces are turned on by default. I figured I can at least try it out for now! @EvanReese
- added an icon. Thanks again! @jelte_steur_info
- added tangent propagation
I'm sure some other stuff I did escapes me, but these are the major changes. I encountered a few bugs that I'm unsure how to fix yet.
Known bugs for now:
doesn't work for edges arranged in a u patternbridging curves fail if one of the edges is common between both sets I think it's fixed now.Looks like these were both caused by the same issue.- I encountered one edge case where trim faces didn't work after I created one other Loft Fillet on the same body. It was for just one specific edge, though.
ry_gb