SOLVED: additive loft calculation differs from subtractive loft calculation

Post here for help on using FreeCAD's graphical user interface (GUI).
Forum rules
and Helpful information
IMPORTANT: Please click here and read this first, before asking for help

Also, be nice to others! Read the FreeCAD code of conduct!
Post Reply
frwi5432
Posts: 6
Joined: Wed Jun 10, 2015 5:20 am

SOLVED: additive loft calculation differs from subtractive loft calculation

Post by frwi5432 »

Hi community!
Just to get familiar with the loft tool I created an additive loft with a circle (XY-plane), slot (45 degree, datum-plane), rectangle (XZ-plane, 90 degree) and after that I created a subtractive loft on the same planes with smaller geometries.
While the additive loft looks ok the subtractive loft is for me not comprehensible.
With the loft tool GUI I could select the inner sketches (circle, rectangle) on the outside of the additive loft, but not the slot in the middle.
Any ideas if I made a mistake or it might be a bug?
OS: Windows 10 Version 2009
Word size of FreeCAD: 64-bit
Version: 0.20.29177 (Git)
Build type: Release
Branch: releases/FreeCAD-0-20
Hash: 68e337670e227889217652ddac593c93b5e8dc94
Python 3.8.10, Qt 5.15.2, Coin 4.0.1, Vtk 8.2.0, OCC 7.6.2
Locale: German/Austria (de_AT)
Attachments
loft001.FCStd
(359.56 KiB) Downloaded 11 times
Loft001.png
Loft001.png (144.94 KiB) Viewed 377 times
Last edited by frwi5432 on Mon Jul 04, 2022 9:08 am, edited 1 time in total.
Regards,
Willy
Bance
Veteran
Posts: 4256
Joined: Wed Feb 11, 2015 3:00 pm
Location: London

Re: additive loft calculation differs from subtractive loft calculation

Post by Bance »

Split the circles into four arcs, loft likes to have the same number of elements per profile.
User avatar
papyblaise
Veteran
Posts: 8002
Joined: Thu Jun 13, 2019 4:28 pm
Location: France

Re: additive loft calculation differs from subtractive loft calculation

Post by papyblaise »

you must have the same number of segments in each scketches: so make the circle with 4 arcs
and they must all be in the same direction
Attachments
loft.JPG
loft.JPG (15.44 KiB) Viewed 353 times
loft.FCStd
(52.16 KiB) Downloaded 5 times
frwi5432
Posts: 6
Joined: Wed Jun 10, 2015 5:20 am

Re: additive loft calculation differs from subtractive loft calculation

Post by frwi5432 »

Bance wrote: Mon Jul 04, 2022 7:39 am Split the circles into four arcs, loft likes to have the same number of elements per profile.
Thanks for your hint
Regards,
Willy
frwi5432
Posts: 6
Joined: Wed Jun 10, 2015 5:20 am

Re: additive loft calculation differs from subtractive loft calculation

Post by frwi5432 »

papyblaise wrote: Mon Jul 04, 2022 7:42 am you must have the same number of segments in each scketches: so make the circle with 4 arcs
and they must all be in the same direction
Thanks. It works fine now.
Regards,
Willy
Post Reply