hydrometer guess

[benharper13]

so I took a hydro reading pre boil but I forgot to adjust for temp it was probably around 100-130 temp. it was 1.035. Then I broke my hydrometer and didn't take a post boil OG I boiled off about 2 gallons or more, I assume this means my OG would be quite a bit higher then my pre boil but I'm not sure is there a formula for this?

 

[brewinjunk]

So adjusted for temperature (let's say 120F), your Pre-boil gravity should be around 1.046, so if you have (46 pts)x(pre-boil vol.) = (X pts)x(post-boil vol.). Solve for X.

 

[Dogphish]

how many gallons before and after boil?

 

[benharper13]

Pre boil about 7 gallons postboil 4.5

 

[brewinjunk]

1.071

 

[benharper13]

Wow that seems high. I did a fat tire clone I copied dudes recipe from the recipe board, I guess it is just because of the big boil off