Still don't understand Specific Gravity

[Duane_Austin]

Can somebody help enlighten me on SG?

I understand OG and FG (I think), and reading glossaries and stuff, thought SG was just the umbrella term to cover these.

But now I'm thinking I don't understand it at all after reading recipes over on hbd.org.

Consider:
Oktoberfest Style Ale

OG: 1.057
FG: 1.014

then I see down at the boil notes:
SG: 1.086

What is that? Now I'm really confused.

 

[llazy_llama]

SG = Specific Gravity, the unit of measurement used to determine density. Sometimes also used to mean Starting Gravity.

OG = Original Gravity.

FG = Final Gravity.

The reason the SG at the boil is so high compared to the recipes OG is because it calls for a partial boil. Extract + 3 gallons of water = 1.086. Post boil wort + top off water = 1.057. I have no idea why they would mention the SG of the boil, seems like over analyzing things to me.

 

[menschmaschine]

I'm thinking he didn't do a full boil and topped it off with water to 1.057. You're right... SG is the parent term for both OG and FG. To be technical about it, OG and FG should really be OSG and FSG.