Hello I am not a designer, i just wanted to try out to have fun with uMake. I was trying to make a half circle coach. For the place where we put out backs’ top i wanted to make half circle as well. I did put a half circle at the edges in order to use the extrude, along the path, I believe it follows from the middle point. I tried to make a middle line but, it was an unsuccessful process. Is there an easy way to achieve this?Untitled.umk (20.8 KB)
My first time using app like this I hope start is okay 
Hi @onqun,
Sorry for the delay! 
I created a quick video for you on how to achieve it, the main feature i used is “Offset” - i created the arc and then used the offset tool once to create an inner arc then another time to create an outer arc. Then I drew a line that intersects with al arc and erased unnecessary lines.
After that I used Push & Pull and at the end “Fillet/Chamfer” to round the corners of the inner part of the sofa (you can use it on other surfaces as well).
https://forums.umake.xyz/uploads/default/original/1X/9c3c9cbf9c7a693fadbc01dd531af51f1b640332.mp4
Let me know if this helps.
Thanks,
Evi