Just Another Gravity Question (or Reading Gravity from a Conical)

[lucianthorr]

I typically brew partial mashes and I feel like I'm really getting comfortable with the whole process. The only thing that never seems to line up for me is any resemblance to predicted OG or FG readings.
I went from using a hydrometer to refractometer last year hoping that would solve the problem but it's still wacky to me.

I know that predicting OG can be off when brewing extracts but I'm still wondering if there's something I'm missing.
I brewed a DIPA 10 days ago and was so excited to see an OG of 1.085. I was finally feeling like I figured it out. But after 7 days, it read 1.037 and then three days later 1.045. It went up?

The last two times I brewed this recipe, it bubbled for almost two weeks but this time it stopped after a week so I'm on the fence on whether it's stuck or just done.

My method for taking readings is pulling about half a tea cup from the racking arm of my little conical, giving it a little stir and then putting a healthy amount of it on the refractometer.
Does anyone have a method for reading from a conical that's different that they prefer?

 

[Iseneye]

In general don't use a refractometer for fermentation readings. Try a hydrometer instead.

 

[PADave]

That's is why I quit using a refractometer, very inconstant readings. Not to mention, once fermentation starts you can't use one without a correction factor. With extracts, as long as you add the proper amounts of water and ingredients, your OG should be right on.