Questions concerning the alignment of and alignment with cylindrical holes...

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R23D
Posts: 135
Joined: Sat Jan 25, 2020 5:23 am

Questions concerning the alignment of and alignment with cylindrical holes...

Post by R23D »

OS: Windows 7 SP 1 (6.1)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.22522 (Git)
Build type: Release
Branch: master
Hash: d8e476ef428017900dfe0f9359ba448503c216f9
Python version: 3.8.5
Qt version: 5.12.6
Coin version: 4.0.0
OCC version: 7.4.0
Locale: English/Australia (en_AU)

Let's say I'm using the Part workbench and I create a cylindrical hole though a part and for reasons, I need to rotate that part through a random number of degrees WITHOUT using that cylindrical hole as the centre of rotation. My hole, of course, more than likely, now doesn't line up with the grid anymore. My questions are 1. Is there a simple way to reposition the part at a later point in time such that the centre of said hole realigns perfectly with the grid and 2. Is there a simple way to align other sub-parts with the exact centre of cylindrical holes that are not currently aligned to the grid? Any help greatly appreciated. :D
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Roy_043
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Re: Questions concerning the alignment of and alignment with cylindrical holes...

Post by Roy_043 »

Try using Draft_Move in combination with Draft_Snap_Center.
R23D
Posts: 135
Joined: Sat Jan 25, 2020 5:23 am

Re: Questions concerning the alignment of and alignment with cylindrical holes...

Post by R23D »

Thanks for the suggestion but I think that Snap to centre is only intended for use with circles and arcs not the negative space of a cylinder left by a boolean differencing operation... and to be honest I can't even get it to work with circles and arcs... Maybe it's me but I find a LOT of the 'snap to' tools in Freecad don't work or only work under very limited circumstances... To be honest, even the most basic 'snap to grid' operation seems to stop working if you try to snap to a grid point over the part you are building... I've been meaning to query that as no other program I have ever used with a grid works that way and freecad's behaviour in this regard seems less than helpful but I should probably make a new post to ask questions about it...
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Roy_043
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Re: Questions concerning the alignment of and alignment with cylindrical holes...

Post by Roy_043 »

One of the issues with using Draft snap is that you should not activate them all. Certainly the near snap is best avoided. I confirm that you cannot snap to the grid when there is a face 'in the way'. It is one of those known FreeCAD problems. But snapping to the center of a cylindrical hole is definitely possible (note: you need to click a circular edge) and entering 0,0,0 as the target point should not be a problem.
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R23D
Posts: 135
Joined: Sat Jan 25, 2020 5:23 am

Re: Questions concerning the alignment of and alignment with cylindrical holes...

Post by R23D »

Ok. Thankyou very much for solving this problem for me. It worked like a charm! I think I have completely misunderstood the snapping tools in Freecad... normally in a program one takes the mouse to the area near the snap point not to the outer perimeter of the shape concerned... got it! :D
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easyw-fc
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Re: Questions concerning the alignment of and alignment with cylindrical holes...

Post by easyw-fc »

R23D wrote: Wed Oct 21, 2020 3:02 pm Is there a simple way to reposition the part at a later point in time such that the centre of said hole realigns perfectly with the grid and 2. Is there a simple way to align other sub-parts with the exact centre of cylindrical holes that are not currently aligned to the grid? Any help greatly appreciated. :D
you may have a try with Aligner of [ur=https://wiki.freecadweb.org/Manipulator_Workbenchl]Manipulator Workbench
[/url]
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