Refractometer Trial

I got the first chance to test out my refractometer yesterday. It was a $25.00 one off eBay that also has a ABV% scale on it.

After chilling my wort I took a reading at 16.333 (estimate) which converts to 1.067 SG. My hydrometer recorded 1.067-1.068.

I'd say thats pretty close. I'm going to continue during the fermentation process and see how accurate it is till the end. I will be using this sheet to account for the alcohol error: http://morebeer.com/public/beer/refractbeer.xls

I think using the refractometer will be simpler and much less evasive of a procedure to check on the fermentation.


edit: this is the refractometer I bought. I think anything similar will do.

Its the best investment I made in brewing. Adjust for temperature, uses just a drop of wort (though i still pull a sample when i want to taste), and has a screw to calibrate it with water back to 0.

A refractometer should be more accurate than a hydrometer, I would think. I don't think I could ever use a refractometer with beer because of all the years we used one to check urine concentration in the ICU.

Can you post a link to the unit you purchased? How do you get the drop of wort on it for measuring?

I got this one (three years ago, not endorsing this seller or saying he's bad, just the first one that popped up on ebay)

http://cgi.ebay.com/NEW-0-32-ATC-Br...emQQptZLH_DefaultDomain_0?hash=item5ad8507c87

you use a pippette. its like an eye dropper. i use my thief to grab a small sample, put a drop on the refractometer and sample the rest. You'll have to use the XLS sheet OP put up to measure alcohol.

I bought one a couple months ago, it just collects dust. The readings are all over the place unless it's just plain sugar solution. I've seen talk of "calibrating" the refractometer to match the error between wort and sugar solution, but in my testing, the error has been +/- 1 degree plato~4 degrees SG with different batches of wort. Just not acceptable in my opinion. I've tested my hydrometer with precise sugar solutions and it's dead on. I go with that.

A couple of comments on refractometers.

(1) I brew with my tap water, so that's what I used to calibrate it. My thinking is that this will "zero out" any gravity contribution from the minerals or whatever that are in my tap water.

(2) refractometer readings are only accurate "as-is" for OG readings. Once fermentation has begun, the alcohol present in the beer will throw off the reading of the refractometer. But, if you have the pre-fermentation refractometer reading, there is some math you can do with to convert a post-fermentation reading to gravity. Here's a link to an on-line calculator that will do this for you: http://www.onebeer.net/refractometer.shtml