See if this gives you any clues. 

http://filemakerhacks.com/2012/09/23/export-field-contents-as-utf-8/

You can export in any of the "text formats" and NAME the file with '.txt'. The format of the export varies, of course. If you put all the text into a single field, you have the Export field contents, and may run into the problem addressed by the article. 
-- sent from myPhone --
Beverly Voth
--

On Jul 6, 2014, at 1:49 PM, Charles Hartley <[log in to unmask]> wrote:

I'm using FMP13 and want to export to a plain text file. Is there a way to do this? Specifically, I want to directly create a .txt file rather than a .tab file.

Thanks,
Charlie