How about, every time he starts talking to you, ask him to do something for you? “Oh, great that you’re free. Could you please take this down to HR?”
Pick up your phone.
Dial their extension.
When their phone rings, tell them “I think I hear your phone ringing”.
Eventually, you won’t even need to dial their phone. Simply telling them “I think I hear your phone ringing” will cause a Pavlovian response to get up and get away from you.
Bonus points if “this” is a manila folder full of pictures of male genitalia in various artistic media (mediums?).
You could try, “Sorry, busy now.” Over and over again. And no eye contact.
The general rule for feedback is:
"When you do X, (clearly yet neutral description of behavior) that bothers me because Y (negative consequence for the speaker). "
“You often start a friendly chat with me. That would be great, but I’m the kind of person who would rather just either talk work-related stuff, or with the friends I have here. Otherwise I would really rather not chat. It’s nothing personal. Sorry. Is that okay with you?”
People are ignoring the “gracefully” part. So, basically follow the advice proffered, but in addition wave about some sheer, silk scarves.
Good, but I think the last question should be omitted. What if it’s not okay with him?
I’m a talk-talk-talker. Like kunilou, I work through issues by discussing them. I might not read cues like one word answers or silence. But if you say to me “I’m sorry, I need to get some work done right now,” I will shut up and leave you alone. I think you just need to be clear and direct.
I think there is a big difference between talking to someone you share an office with and talking to someone else while the person you share an office with is right there, so I don’t see any hypocrisy in his asking you to be quiet so he can work.
You might consider saying something like “I know it’s disruptive to you when people come and talk to me while you’re trying to work. I’ll take the chat to the breakroom next time.” Then do that. Separate the chatting space from the work space. Then the next time he starts to chat, say, “I don’t have time to take a break now. Maybe later we can go to the breakroom and chat.”
It sounds artificial when I type it up, but it really can help to establish boundaries and space-appropriate behaviors. Of course, you need to stick with it, too.
My life became easier once I realized that people who ignore social constraints do not require the same courtesy as the less dense.
He won’t be upset by a straightforward message, or if he is, it’s because he’s got a toddler mentality.
‘‘I have a lot to do today, so I’d better get back to work.’’
It works even for people I really like.
The OP should copy the image of that shirt (ideally a larger image, but that’s probably not hard to find), save it into MS Paint, print it out, and tape it to the side of his cube.
When he wants the talker to shut up, he just points at the printout.
I prefer weasels. Rabid weasels, if possible.
ETA: But not a rabid Spice Weasel. That’s just overkill. 
+1.
Post #2 
Roddy
I can imagine saying that to a friend or to a complete stranger, but to someone who you have contact with who doesn’t know you that well? Seems like a dumb idea both then and now.
I don’t understand the desire of some Dopers to create drama.
[QUOTE=BigT]
**Caesin is not dairy free, you fuckers!
**
[/QUOTE]
Not drama?
Sorry, I was a bit unclear. “My office” has four cubicles in it. I sometimes talk to the other two people in the office.
I don’t think this changes our point, which is that if you want this one person to stop chatting, in your work area, the most equitable way to do that is to make the work area a non-chat zone. Take your chats somewhere else. Ask him to do the same.
Roddy
I agree that that is how it should be, but I’ve worked in enough offices to know that it never is that way - people love to talk, and they love to talk with the people around them.
So, to make sure I’m understanding this, the office is made up of four cubicles. The OP talks to two of the people in the other cubicles, and has a problem with the person in the fourth cubicle, who talks and talks and talks when HE wants to talk, but shushes the OP when he is talking with the other two people in the office.
I don’t think you can have it both ways; I don’t think you can chat with the other two people, then shut down the third when he wants to talk, even if he does talk more than the other two. I think the cubicles have to be a Quiet Work Zone for everyone or no one.
That said, if you have normal co-workers, they usually are good at finding a balance between working and chatting (now we all get our work done; we’ve worked for an hour or two, so now we can chat for five minutes); Mr. Chatty doesn’t sound like he is able to do that.
I don’t mind it when he to talks to someone else in the office. I just care when he talks to me. I don’t know if that makes a difference.
Larges will get more attention.