[V0.16] Align Plane to Cone Wall

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ppemawm
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[V0.16] Align Plane to Cone Wall

Post by ppemawm »

REFERENCE viewtopic.php?f=3&t=22074 Reddit cad challenge23

For those of us who are not planning to migrating to V0.17 any time soon, I thought it might be helpful to show new users how this object can be created with V0.16.
Picture1.jpg
Picture1.jpg (65.07 KiB) Viewed 572 times
The work flow is similar to V0.17 but instead of datum planes you must create features that have faces that serve as datums. This takes some planning before starting the model and a bit of experience using this method. This approach makes extensive use of external geometry references so the model may not be too stable if any changes are made to the completed model. Hopefully, V0.17 will remove this limitation.

Although there may be other approaches, I took the following steps using the PartDesign workbench:
1. Revolve the basic conical part as a solid (not hollow)
2. Pad a basic feature that locates the two angular faces necessary for the two bosses. Include a square hole to locate the centerline in the pad.
3. Pocket away the two faces at the cone angle determined from the revolve master Sketch
Picture2.jpg
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4. Attach sketches to the proper faces to pad the boss features. The pads are located using the external geometry vertex on the center bottom of the datum feature pad from step 3. Use the Type/Two Dimensions to pad the bosses. The first dimension is determined from the sketches in step 3 and the second is arbitrarily chosen to insure that the pad completely intersects the cone.
Picture4.jpg
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5. The conical part is hollowed with the Groove tool that uses the vertical axis and a copy of the master Sketch located on a face of the square hole feature from step 2
6. Add a pocket feature in boss1 to locate the 'Select Reference...axis' for the PolarPattern tool as highlighted in the following picture.
Picture5.jpg
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7. Pocket the holes in boss1 and boss2
7. Complete the model by pocketing away the datum feature created in step 3
V0.16_challenge23.FCStd
(456.85 KiB) Downloaded 16 times
OS: Windows 8
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.16.6706 (Git)
Build type: Release
Branch: releases/FreeCAD-0-16
Hash: f86a4e411ff7848dea98d7242f43b7774bee8fa0
Python version: 2.7.8
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17
"It is a poor workman who blames his tools..." ;)
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NormandC
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Location: Québec, Canada

Re: [V0.16] Align Plane to Cone Wall

Post by NormandC »

Hi ppemawm,

Good idea to post this alternate method compatible with 0.16! :)

Although I must admit that with the new stuff in 0.17-dev, I find it more and more difficult to stick with 0.16...
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