Hi there,
I updatet my Rhino8 from 8.24.25.281.15002 to 8.25.25314.11002 on mac.
Since the update the sweep1 component in grasshopper is extruding in the opposite direction. The bug happened on two different computers with the latest update and it didn’t appeared on a computer with older Rhino Versions like 8.24.
Attached is a screenshot of the file opened in Rhino 8.25. Also the two files.
hope you guys can fix it for the next update or show me that I’m wrong 
Paul
Hello Hannah, I am not an expert in Rhino versions, so do not know if there is a a bug, but I have an explanation.
See image below. You see that the starting point of your rail is at the opposite side of the line.
For the extruding sweep start at starting point and extrudes along curve to endpoint. Giving the cylinder you showed.
A simple flip curve is enough to let it work in the other direction.
PS: Please internalise the material you have, save uploading the 3dm file.
Regards, Eef
Hi @LOMA,
This was broken in Rhino 8 sr25 release. Grasshopper Sweep 1 started using Global blending, instead of local, with no options for inputs. This has was not detected and sr25 was released and it should be fixed in in sr26 service release.
If this is an issue with your GH definitions, you can uninstall Sr25, and go back to Rhino 8 sr24
Windows Rhino 8 sr24 or Mac Rhino 8 sr24
Turn off the automatic updates, until Rhino 8 sr26 is available.
Options → Updates and Statistic, disable automatic updates.
Hope this helps.
Sincerely,
Mary Ann Fugier
Thank you very much 
RH-90489 is fixed in Rhino 8 Service Release 25
I still noticed different behaviour in the sweep1 component in 8.25.25328.11001, compared to earlier versions. Going back to SR24 helped, so I will stick with that version for now.
When the sections are not connected to the rail, a surface is created between the sections as expected in SR24. In SR25, the surface is extended to the start and the end of the rail. The behaviour of SR24 matches what I would expect, based on how the Sweep1 command behaves in Rhino.
Can you post an example file which works correctly in 8.24 but fails in version >= 8.25?
Attached is a Grasshopper file with a couple of internalized components that shows the difference between SR24 and SR25. As can be seen in the screenshots below, SR24 creates a surface between the three profile lines, whereas SR25 extends the surface to the start and end point of the rail.
sweep1_test.gh (3.0 KB)
Without reading this thread (or trying any posted GH files), I this a bug 
(per title)
P.S. Oh, this one? Fixed three weeks ago?
I have NEVER seen Sweep behave as you describe 
And am alarmed to see the dramatic difference when I open your test GH file in R7 vs. R8 
This is your same geometry with some traces I added, including an experimental Loft of the stations used by Sweep - not the same
There was a good reason why the change was made to the Sweep 1 rail component around version 8.25. However, it seems that this change has had a larger impact on various other types of files, so it was decided to roll back all of the code that was introduced and make the component behave as it did in version 8.24. So, with the release of 8.27 RC 1 (which should be released later this afternoon), the Sweep 1 rail component should behave as it did prior to these changes. We apologize for this inconvenience.
If it was easy to do…. thank you to you and your team for outstanding technical support
