# Loop-cut won't go all the way around

Alright so I've seen some postings about loop cuts and done some research. I am very new to blender and modeling overall. I am trying to loop cut this concrete barrier. Now I'm following a tutorial and kind of did my own thing in some areas. I cleaned it up following some instructions in another answer here on stack exchange.

I can't for the life of me figure out why I can loop cut around the whole bottom:

...but not the whole middle:

I see this marked as answered by another question. That question refers to ngons and inside faces. Now once again I'm totally new to this. I looked on the inside. I don't believe I have inside faces or any ngons by the terms I've read online in my research.

Here is a wireframe picture and the inside view:

Maybe I'm missing something the answers on other posts are saying. If so and you know what it is I'd be very appreciative of what it is.

• See the first answer on the other post. You have a ngon on the bottom of your mesh. – iKlsR Oct 17 '14 at 4:21
• Just tried removing that ngon because I realized it. It has no effect on the loop cut for the area I'm trying to work on. Any ideas? – CrazyGrunt Oct 17 '14 at 4:38
• I initially marked as a duplicate of this since the answer is on the other question but since you are new, I think this could get an answer. – iKlsR Oct 17 '14 at 4:40
• – gandalf3 Oct 17 '14 at 6:19
• – gandalf3 Aug 27 '15 at 8:57

This is because the bottom face doesn't have the proper geometry, the edge ring tool doesn't know where to direct the ring since there are several vertices (it is an ngon). You can only use this tool on quads (4 sided faces). So to fix, you can use the knife tool and rework the ngon into a large quad.

Additionally, there is also another problem, you have duplicate vertices at the point where the cut stops. To fix, first box select (B) the points shown below and use Alt + M > At Center to merge the duplicate points into one.

After you do that, use the Knife Tool (K) to create a quad as shown below. Press K and select one vertex then another and press Enter. Repeat for the other side and you should be able to add edge rings after.

• How do you know when you have duplicate vertices like that? Aside from that I will give this a try tomorrow. Thank you for the help. I spent a while trying to do this on my own and even asked a friend who uses Maya, but she wasn't sure. – CrazyGrunt Oct 17 '14 at 5:06
• It depends, in this case, it was hidden as it was right on top of the other, I noticed because the edge cut stopped there instead of the large bottom face. Additionally, you can sometimes use W > Remove Doubles to check for and clear these. – iKlsR Oct 17 '14 at 5:09
• I see. I just dragged the vertices and got that, Aha! moment. Thanks for all the help. I learned a lot just from this alone. – CrazyGrunt Oct 17 '14 at 5:11
• I looked it over and found more double vertices. I removed those and it allowed me to get the loop cut around barrier the long way. Thank you so much for pointing out the vertices issue along with the ngon and helping me. This was super helpful. – CrazyGrunt Oct 17 '14 at 18:11