Offset failed

Hello everyone! :smile:
first post here and … a quick question !

I’m trying to design a simple chair (rhino 4) but I’m having issues with the offsetsrf command …

first I did the outline of the chair , then a fillet and I created the surface with the edgesrf command
but when I try to add some thickness to the (let’s say) plywood surface , I get an ‘‘offset failed’’ …

any ideas please ?

thanks in advace!!



Hi Lef- can you please post the file?



thanks Pascal for your answer !
a friend of mine helped me to find the solution !