Trouble hollowing a "loft"

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Milo_1008
Posts: 2
Joined: Sun Aug 30, 2015 4:00 pm

Trouble hollowing a "loft"

Post by Milo_1008 »

Hello, everyone.

I´m pretty new at FreeCAD, but I´ve been following a tutorial series and I´m loving it.

I need to make a 3D printed vacuum cleaner adapter and I have modelled it really fast thanks to the "loft" option in "Part" workspace:
Image

This was pretty easy, but, when I try to hollow it leaving only a 3mm wall on the inside with "Thickness" it gets it all wrong.

I´ve been trying for hours with no result. Any ideas?

I´ve attached the file so you can play with it if you want.

Thanks everyone for your time and excuse me for my rusty English.

My system specs are:
OS: Windows 8
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.15.4671 (Git)
Branch: releases/FreeCAD-0-15
Hash: 244b3aef360841646cbfe80a1b225c8b39c8380c
Python version: 2.7.8
Qt version: 4.8.6
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17
Attachments
adaptador soplahojas.FCStd
(8.1 KiB) Downloaded 39 times
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DeepSOIC
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Posts: 7896
Joined: Fri Aug 29, 2014 12:45 am
Location: used to be Saint-Petersburg, Russia

Re: Trouble hollowing a "loft"

Post by DeepSOIC »

Hi!
Part Thickness should do exactly what you ask, but I can't get it to work with your shape. It is known to have problems without obvious reasons. I think you'll have to model the inside repeating a similar loft, and cut it out.
jmaustpc
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Posts: 11207
Joined: Tue Jul 26, 2011 6:28 am
Location: Australia

Re: Trouble hollowing a "loft"

Post by jmaustpc »

DeepSOIC wrote:I think you'll have to model the inside repeating a similar loft, and cut it out.
Here is an example of what Deepsoic is talking about
notes
1)for reliability it is best to avoid coplanar faces with a Boolean hence I moved the first and last sketches up/down 1mm
2)to constrain a sketcher ellipse you can create one or two lines, multi-select the lines then the ellipse, then go to PartDEsign menu ....sketcher constraints sub-menu ...."constrain internal alignment". This will put construction lines on the Ellipse on its axes.
3)for reducing the circle radii, you can enter normal maths into the input box, so double click on the radius constraint then delete the "mm" and type "-3" and FreeCAD will calculate it for you.

adaptador soplahojas.FCStd
(31.61 KiB) Downloaded 32 times

Jim

OS: Kubuntu 12.04.5 LTS
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.16.5403 (Git)
Build type: Debug
Branch: master
Hash: cac09437c8824df247029a09c3b946520bea63b9
Python version: 2.7.3
Qt version: 4.8.2
Coin version: 3.1.3
OCC version: 6.8.0.oce-0.17
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