Refractometer Woes

[PeterB]

Hi All

I am trying to get used to using a refractometer I purchased a month or 2 ago (https://www.amazon.co.uk/gp/product/B01FVTL044/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&th=1)

I have taken some drops of water from the lid of my kettle and used that to baseline it to zero. Then when measuring my beer which has been fermenting away for days and has now stopped - my hydrometers (x2) both read 1 on the nose (kveik rocks). The refractometer reads a tiny bit over 6 brix (say 6.2). When I stick this into an online calculator (or several), they suggest this converts to sg of 1.024.

Have I got a dud? Is my baseline method wrong? Help!

 

[LeeH]

They don’t work post fermentation without a calculation fudge.

However, they work very well for pale beers pre fermentation. And close enough for me on dark beers.

 

[RichardM]

If I was you I'd stick to using the refractometer for checking gravity pre and post boil and carry on using a hydrometer to check that fermentation is complete.
But to answer your question why not compare your calculated value with a reading from a hydrometer?

 

[PeterB]

Thank you. Reading your posts and a little investigation, I was trying to do the wrong thing.

I will try and use it right next time, but this time I didn't bother getting a reading before fermentation so will stick with hydrometers.

 

[Brew_DD2]

Loads of online calculators will correct for alcohol content in finished beer for refractometers.

 

[LeeH]

Refractometers are much better on brew day imo.

 

[pottsworth]

I use this with a correction factor of 1.02, and it's normally within a couple of points of what my hydrometer says.

https://www.brewersfriend.com/refractometer-calculator/

I use an iSpindel for tracking fermentation, so am not too bothered about using fg to confirm fermentation is complete, just to work out final ABV.