How much time will i have to wait until google completely reindex my site?

Selected answers from the Dumb SEO Questions Facebook & G+ community.

• 
  Mimetix: Hi, i recently changed drastically my website. I sent the new sitemap n WMT and it has around 40 pages. The problem is that after 2 weeks, there are still 190url indexed and lots of 404 errors. I sent again my main url checking "my site has changed". How much time will i have to wait until google completely reindex my site?
• 
  Andy Wigglesworth: hi +Mimetix ;
  
  It really just depends how often google crawls your website, obviously this varies a lot!.
  
  So, you did a fetch as Googlebot in WMT?
  
  Also, did you setup any 301 redirects from pages that you've moved/changed.
• 
  Mimetix: +Andy Wigglesworth ;ty for your answer. Well, about 301 redirects, i didnt. There are  ;many links i should redirect that no longer exist. I changed the page structure so i thought 301 redirect was unnecessary, as google should just remove those links with time. What i redirected were incoming links from other pages so they dont come to a 404 page. Do you recommend me to 301 redirect every old
  url to the main domain?
• 
  Andy Wigglesworth: Before I get to answer (if I get chance, about to goto bed), I forgot to ask you to remove your URL from your question, so if you could edit, so it just shows mimetix (dot) com - it's the rules of the community...
• 
  Mimetix: +Andy Wigglesworth ;done ^^
• 
  Andy Wigglesworth: Awesome and thanks +Mimetix ;- you can put mimetix (dot) com in your question so people can copy/paste!
  
  I'll take another look at this in the morning - early start for me 5.15am, so early bed tonight...
  
  However, I am sure someone else may chip in the meantime!
• 
  Matt Staton: 301's for sure
  
  Did you build a new xml sitemap? Did you submit it to GWT etc.
  
  Do you have a robots.txt? Sometimes I've seen where people push a robots.txt file to production and it's actually blocking everything.
• 
  Mimetix: +Matt Staton ;yes to all :)
• 
  Andy Wigglesworth: Yeah, there are still quite a few 301's that you can still implement, for example - ;
  
  mimetix dot com /marketing-internet/
  
  to
  
  mimetix dot com /en/sem
  
  If you do a ;site:mimetix dot com google search to see all your urls...
• 
  Clayton Nichols: Yes, 301 redirect those expired pages to live pages. Excellent advice given here. ;
• 
  Mimetix: ty all guys :D ill do as you say