Cylinder won't extend

cylinder.3dm (86.5 KB) I can get the right end to extend ,but not the left. —Mark

Hello Mark

If you run _showedges, you will see that on one edge you have 2 points next to each other.
go to Analyze --> Edge tools --> merge edge, select that edge
After that you will be able to extend that edge.

Have a great weekend
Dan

Thank you, Kunf