I hope this helps to get you back on track. Hang in there! It's always a struggle in the beginning.

The tutorial is beginner level but it has techniques that are designed to prepare you for the...

I just noticed you have two other triangles that do not match the topology of what is in the tutorial.

As a general rule triangles and ngon (polygons with more then four sides) should be avoided. ...

I found the section in part 2 of the tutorial and the problem is the triangle. I place both those edges to make the bend in the side close too the vertex's on the left and right side of the can.
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The issue most likely has to do with the triangle. The edge you have selected runs through a triangular poly. When you apply a tool like offset edge Maya does not know what to do when it hits the...

Sorry I am not understanding the problem as described. Can you maybe grab a couple more snapshots maybe before and after and zoom out a bit more so I can see more of the entire model.

Hang in...

I just watched that section and after the extrusion I accidentally say hit the d-key which was a mistake but corret it and say hit the "delete" key to delete the back face (Like I showed above).
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First I apologize for speaking to fast.

Watch this and it should make more sense what is happening.

jerry can tut question - YouTube...