V19 quirks

[SpaceCase]

Like this?

[Bance]

Yes, did it stop the error?

If you change the position of the first hole in the polar pattern, things get tidied up a bit.

PGB.png (51.1 KiB) Viewed 194 times

[SpaceCase]

Yes, in fact it Constrains the Sketch more efficiently - fully Constrained with fewer Constraints. Thank you also for the tip about rotating the Polar Array.

Now that I know all these knowledgy FreeCAD things, it's time to re-construct the Real Bowl this efficienter, stabler way. It has a more complex topography than the Practice Bowl, and switching to Tangency Constraints throws it wildly out-of-shape, so I'm starting back from Scratch and fortunately learned how to shrink and grow the other pieces by changing their Sketches, before the Real Bowl went haywire. So now, with Endpoint Tangency, I will have a Real Bowl truer to Nature than my

convoluted method of creating tangency constraints

, which I didn't even know I was creating Tangency Constraints; just hooking things together as simple as possible to easily re-create the Sketch, because I get all mixed up trying to Copy Sketches and Mapping them and everything always goes KerBlooey.

Thank you for your patient, knowledgeable tutelage (I sure love SpellCheck!); I could not become an adept FreeCADder without you and chrisb and GeneFC, drmacro and everyone else on your helpful team.

[Bance]

You're welcome

[SpaceCase]

Well, Heck, here I am again, quirky as ever. This may be a FreeCAD quirk, or prob'ly not, but I swear I have re-checked the dimensions many times, and they all add up to a vertical sidewall, yet it appears slanted. Here's the Main Pad of the Real Bowl. (Body001 is temporary, trying it on for size to then re-create it in a separate Document. It's just a Pad Disc, same Diameter as the Core Pad, with lips on its rim.)


You can see on the Right End front view, it is vertical:

TempSnip1.PNG (44.23 KiB) Viewed 129 times

, whereas the Left End is slightly atilt:

TempSnip2.PNG (43.86 KiB) Viewed 129 times

. This tiltedness is more pronounced when a the first Groove is visible:

TempSnip3.PNG (41.3 KiB) Viewed 129 times

, and the Sketch for this Groove does not line up, even though its parts add up to the same diameter as the Core Pad and Body001:

TempSnip4.PNG (48.52 KiB) Viewed 129 times

All the Lines in the Groove Sketch are constrained to vertical, the outside edge of the Sketch is constrained Vertical from the Diameter of the Core Pad, and the datum Constraints all add up to the diameter of the core Pad and Body001, so is this tilted sidewall due to crappy hardware, or a FreeCAD quirk, or maybe those Tangency Constraints are stretching the curves a little, or maybe there's some flaw in my strategy or design, which is the most likely scenario, but if it's a bad Sketch, wouldn't the sidewall be tilted all around, instead of just where the Sketch is?

Will you please share your thoughts on this? Thamks.

HW: Intel(R) UHD Graphics 600
OS: Windows 10 Version 2004
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.24276 (Git)
Build type: Release
Branch: releases/FreeCAD-0-19
Hash: a88db11e0a908f6e38f92bfc5187b13ebe470438
Python version: 3.8.6+
Qt version: 5.15.1
Coin version: 4.0.1
OCC version: 7.5.0
Locale: English/United States (en_US)

Also some interesting co-planiarity things came to light with the Pipe and the Pipe Pre-Pocket. Basically, when I pocket out a pathway the same Outer Diameter as the Pipe, I get an error about the Pipe not being a solid, since it's like half a micron away from the inside of the pathway, so if I make the Pipe Pathway Pocket the same diameter as the Inside of the Pipe, the Pipe then intersects the Bowl and FreeCAD finds it solid. Best Practice here would be to make the Pipe Pathway Pocket smaller than the Pipe Outside Diameter, but larger than the Pipe Inside Diameter, to avoid coplanarilaty (cylinder-style) on the Inside and Outside of the Pipe.

[chrisb]

Is this to be seen with the latest file uploaded by Bance?

[Bance]

This a new file, I think.

Want to post a file?

[SpaceCase]

No, it does not appear in the last file uploaded by Bance, even after I put in the lips:

TempSnip3.PNG (43.07 KiB) Viewed 65 times

This was only a Practice Bowl, to find the best way to put and trim the Pipe in the Real Bowl, which has a more complex topiology than the Practice Bowl. My patent attorney would prob'ly scowl very deeply if I revealed its secrets to anyone, at this point, not properly sworn to silence ( I may have said too much already; now you already know it's a GroovyBowl with a Polar Array called 'Slotties'), but I can try to reproduce the phenomenon with similarly complex curvatures unlike those of the Real Bowl.

I have re-read the Sketcher Lecture several times, each time I recognize something I didn't used to know, but learned from Trial and Error or Forum Queries, not the Sketcher Lecture, because partly I can't seem to find the 'Zoom' button on it, and my magnifier app ain't so hot either:

TempSnip.PNG (35.96 KiB) Viewed 65 times

so some readings I just missed stuff, or got lost in the jargon, or otherwise confused, or simply skimming anything not related to the Real Bowl, except now I know it's All Related.

Started out thinking a 'ShapeBinder' was some kind of Master Constraint, to hold selected elements in position relative to one another during move operations, when I thought 'copy and place' was still in vogue. Still don't know Linked from UnLinked; might as well say Flapped or Flipped, for all these descriptions tell me.

Another time I thought '3-D View' meant the Navigation Cube, so Imagine trying to follow a Tutorial saying 'Click anywhere in the 3-D View' and clicking the Navigation Cube instead; my Models kept going Kerblooey, it seemed, but it was just Operator Idiocy after all.

Here's a picture from the Lecture, as it appears on my screen:

TempSnip1.PNG (28.97 KiB) Viewed 65 times

Note the zigs in the vertical edges. These actually ripple as I scroll the image up and down the screen, so I don't know whether I've got a real problem with the Real Bowl, or if it's just a manifestation of cheap hardware (though the Ziggy edge of the Real Bowl does not ripple like the images from the Lecture). If you say so strong enough, I may be able to swing a new computer out of this.

Another thing noticed this last Sketcher Lecture reading - 'Links out of Allowed Scope' messages. I see this from time-to-time, and sometimes after I've re-built something that worked the first time before I tore it down and started over. No clue how to handle it.

Yes, I think a new computer might be in order, what do you say?

TempSnip4.PNG (15.95 KiB) Viewed 65 times

OS: Windows 10 Version 2004
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.24276 (Git)
Build type: Release
Branch: releases/FreeCAD-0-19
Hash: a88db11e0a908f6e38f92bfc5187b13ebe470438
Python version: 3.8.6+
Qt version: 5.15.1
Coin version: 4.0.1
OCC version: 7.5.0
Locale: English/United States (en_US)

[SpaceCase]

I have replicated the problem, and it has nothing to do with convoluted curvatures at all. Decided to rebuild the Real Bowl from scratch, and watch for the zigs to appear. On a hunch, Sketched a simplified Curvature not remotely like the Real Bowl, just random toggles off the Polyline, to see if maybe it was the lips. First I make a big Core, zigless:

TempSnip1.PNG (16.74 KiB) Viewed 51 times

. Next I put in the Slotties (which are simplified and have nothing in common with the Real Slotties), still zigless:

TempSnip2.PNG (18.14 KiB) Viewed 51 times

, then the SlottyScoop and voila! there appear the Zigs:

TempSnip3.PNG (22.86 KiB) Viewed 51 times

. Notice the SlottyScoop Sketch beyond the Core boundary, even though they are Constrained to the same dimensions, which I always when possible type in as integers to truncate roundoff:

TempSnip4.PNG (45.65 KiB) Viewed 51 times

. It also does looks the same when with vertical Constraint from the Construction Line Endpoint instead of the 35mm Horizontal Distance Consstraint. Please tell me it's due to the hardware over here, and that my Model is sound, and we should get a new computer. Thanks.

The Document attached is called 'PretendRealBowl' even though the exhibits say 'RealBowl' , the Document is really the Pretend Bowl.

[chrisb]

I can reproduce your issue here, but it's only a visual thing, the internal geometry is still correct. You can reduce the Deviation in the body's view attributes to 0.1 or even lower and the effect will (almost) vanish.

Sorry, no new computer for you now.