Self centre a primitive to a Datum Plane

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cram
Posts: 150
Joined: Mon Dec 05, 2016 5:11 am
Location: Australia

Self centre a primitive to a Datum Plane

Postby cram » Sun Apr 22, 2018 8:42 am

Trying to get my head around datum planes. I have created two one normal and is positioned along the mid point of the cylinder, the centred along the axis of origin of the cylinder circumference.
I am trying to use a subtractive primitive to remove a section of the cylinder based on these two datum plane however the result if not what I am expecting and appears to remove the whole cylinder, not just a 100mm section using the 100mm subrtractive cube used.


OS: Windows 10
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.13509 (Git)
Build type: Release
Branch: releases/FreeCAD-0-17
Hash: 0258808ccb6ba3bd5ea9312f79cd023f1a8671b7
Python version: 2.7.14
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.2.0
Locale: English/Australia (en_AU)
Attachments
datum_use3.png
datum_use3.png (131.59 KiB) Viewed 436 times
datum_use1.png
datum_use1.png (244.08 KiB) Viewed 439 times
datum_use.png
datum_use.png (180.44 KiB) Viewed 439 times
datum_use.FCStd
(11.14 KiB) Downloaded 26 times
chrisb
Posts: 19043
Joined: Tue Mar 17, 2015 9:14 am

Re: Self centre a primitive to a Datum Plane

Postby chrisb » Sun Apr 22, 2018 9:36 am

I have problems editing/viewing your model, exact analysis has to follow. Here my guess:

The subtracitive box has no connection to the DatumPlanes, so you don't need them.
The box cuts a piece in the middle of your pad, which would yield two solids. This is not allowed in PartDesign, so one of them is suppressed.
cram
Posts: 150
Joined: Mon Dec 05, 2016 5:11 am
Location: Australia

Re: Self centre a primitive to a Datum Plane

Postby cram » Sun Apr 22, 2018 11:07 am

chrisb wrote:
Sun Apr 22, 2018 9:36 am
I have problems editing/viewing your model, exact analysis has to follow. Here my guess:

The subtracitive box has no connection to the DatumPlanes, so you don't need them.
The box cuts a piece in the middle of your pad, which would yield two solids. This is not allowed in PartDesign, so one of them is suppressed.
"The box cuts a piece in the middle of your pad, which would yield two solids. This is not allowed in PartDesign, so one of them is suppressed."

I think this may be my problem. I did not know that PartDesign doesn't allow two solids

I'm a little unsure what you mean by "The subtracitive box has no connection to the DatumPlanes, so you don't need them."
When I created the subrtactive box I chose to use attachment to DatumPlane and DatumPlane001?
chrisb
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Joined: Tue Mar 17, 2015 9:14 am

Re: Self centre a primitive to a Datum Plane

Postby chrisb » Sun Apr 22, 2018 11:21 am

cram wrote:
Sun Apr 22, 2018 11:07 am
I'm a little unsure what you mean by "The subtracitive box has no connection to the DatumPlanes, so you don't need them."
When I created the subrtactive box I chose to use attachment to DatumPlane and DatumPlane001?
Ok, I see. I had problems with viewing the details of your file and still have them when I try to change something.
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DeepSOIC
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Location: Saint-Petersburg, Russia

Re: Self centre a primitive to a Datum Plane

Postby DeepSOIC » Sun Apr 22, 2018 12:17 pm

chrisb wrote:
Sun Apr 22, 2018 11:21 am
had problems with viewing the details of your file
I have them too.

There is something horrily broken about Box:

Code: Select all

>>> App.ActiveDocument.Box.Placement
Placement [Pos=(-2.5e+099,-5e+099,-2.5e+099), Yaw-Pitch-Roll=(153.435,-3.18055e-015,65.9052)]
It is placed in the infinity. How does it happen, I wonder...

EDIT: Ah, I see how. It happens when you use Inertial CS attachment on datum plane. Datum plane is internally infinite, and this bogus result is the outcome.
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DeepSOIC
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Re: Self centre a primitive to a Datum Plane

Postby DeepSOIC » Sun Apr 22, 2018 12:42 pm

User avatar
NormandC
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Re: Self centre a primitive to a Datum Plane

Postby NormandC » Sun Apr 22, 2018 5:13 pm

Hello cram,

cram wrote:
Sun Apr 22, 2018 8:42 am
Version: 0.17.13509 (Git)
A few nasty bugs crept up in the initial 0.17 release, they have been fixed, so I recommend you download and install the latest version 0.17.13515.

Download
cram
Posts: 150
Joined: Mon Dec 05, 2016 5:11 am
Location: Australia

Re: Self centre a primitive to a Datum Plane

Postby cram » Wed Apr 25, 2018 9:04 am

NormandC wrote:
Sun Apr 22, 2018 5:13 pm
Hello cram,

cram wrote:
Sun Apr 22, 2018 8:42 am
Version: 0.17.13509 (Git)
A few nasty bugs crept up in the initial 0.17 release, they have been fixed, so I recommend you download and install the latest version 0.17.13515.

Download
Ok NormanC , thank you will do so.
alberich
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Location: Texas

Re: Self centre a primitive to a Datum Plane

Postby alberich » Wed Apr 25, 2018 9:51 am

NormandC wrote:
Sun Apr 22, 2018 5:13 pm
Hello cram,

cram wrote:
Sun Apr 22, 2018 8:42 am
Version: 0.17.13509 (Git)
A few nasty bugs crept up in the initial 0.17 release, they have been fixed, so I recommend you download and install the latest version 0.17.13515.

Download
The Download page refers to 0.17.13519. Also, the linux appimage is still at .13509. Is that correct?
chrisb
Posts: 19043
Joined: Tue Mar 17, 2015 9:14 am

Re: Self centre a primitive to a Datum Plane

Postby chrisb » Wed Apr 25, 2018 1:17 pm

alberich wrote:
Wed Apr 25, 2018 9:51 am
The Download page refers to 0.17.13519. Also, the linux appimage is still at .13509. Is that correct?
Both are correct. Three days ago Normand was correct as well.