Should I pitch more yeast if I'm nowhere near my FG?

[linusstick]

So I usually just rack my beer to a bottling bucket after two weeks. I'll take a gravity reading before I bottle and if it's higher than it should be...meh... I'll drink it. Now I want to get more technically proficient. My question is this. If you take a beer with an x gravity reading, does that mean it scientifically should be y after fermentation? And if after a few weeks it's not at y you should pitch some more yeast until it gets there? I'm trying to understand some science behind the process and while I've read some things about this, I can't find something about pitching more yeast.
The whole reason for asking is I have Founders Breakfast Stout clone that I will be bottling next Sunday. It will have been fermenting for 2 weeks at that point. Airlock activity (which I know is not the sole indicator) stopped after 6 days. I wanted to take a gravity reading before bottling and wondered if it's too high, will it make sense to pitch more yeast to get it down or just bottle it and be done. I only do 1-1.5 gallon batches so experimenting is fun and not costly. Thanks!

 

[ChelisHubby]

Well in general if your within 5 points I don't worry. yeast is a fickle creature and brewing conditions and fermentation conditions do effect the final gravity. The basic rule is that you take a gravity reading today and one more 3 days later to see if the yeast are done eating, the readings need to be the same.

 

[jtratcliff]

if you're within a few points of your expected FG, then no worries, just typical yeast variability. If you're off by 10, then maybe it's time to have a look at your process...

 

[linusstick]

Yep got that. Even when I hit my targets I am constantly looking at and evaluating my process. But my question still stands. If I am off by a decent margin, would pitching more yeast correct the problem?

 

[wes79]

Well here is my take on this, if there is fermentable sugars more yeast would help. But, adding yeast that is not used to the APV will stress it. Might through off flavors. Try adding yeast energizer and resuspending the yeast. Let it sit another week.

 

[EazyMcBreazy]

If its a high grav that second pitch of yeast will struggle to do much depending on strain. I find racking to secondary helps to finish out the beer. Micro oxygen and re suspends. Nutrient/energizers are aimed to improve cell division which you wont get a lot of but worth a shot if your not concerned about contamination. Boil in water then add as winemakers do