Hydrometer Accuracy?

[Noah]

Hi, I hope someone can help. I replaced my old hydrometer as the readings didn't seem realistic e.g. strong beers reading 1.002 F.G. I replaced it recently with a new Munton's hydrometer which seems to be reading high, 12 points higher than the old one.

I've had Woodeforde's Headcracker brewing for over a month at almost a constant 20 degrees. I checked the gravity today and it's reading 1.030 with the new hydrometer and 1.018 with the old one, which is where it should end up.

I'm reluctant to bottle it at such a high reading and I'm inclined to buy another hydrometer to see what that reads.

Any advice, shall I go ahead and bottle? Are there more accurate methods or equipment I should be using?

Thanks.

 

[Dutto]

The accuracy of a hydrometer can easily be checked by dipping it into water at 20 degrees Celsius; when it should read 1.000

If it doesn't then simply adding or subtracting (as required) the difference will give an accurate SG.

Also, the ABV calculation is made on the difference between the OG and FG so the accuracy of the hydrometer is not a problem when calculating the ABV.

Hope this helps. :thumb:

 

[Noah]

Thanks, they're both out by about 4 so if I deduct that from 1.030 it's still too high to bottle. I'm sure fermentation has finished but I don't want any bottle bombs!

 

[ericmark]

There are two temperatures used with hydrometers 16°C (60°F) and 20°C also temperature correction varies with plastic or glass used to make them. There is no universal temperature correction chart only the one which comes with the hydrometer is valid.

I have seen where a hydrometer has been dropped how the paper giving the reading has moved inside the glass, mine it is printed on the glass, since the hydrometer used for beer does have a 1.000 shown simple method is to test in water, at the temperature that the hydrometer uses.

The plastic one I had was really easy to read and was very good until it sprang a leak. But it went the reverse direction to a glass one with temperature correction.

 

[whinton]

I use a Hydrometer and a Refractometer. I usually use both for the OG and just the Refractometer for the FG. Reason for this is that I get a good comparison at OG stage and by using the Refractometer at the end of fermentation, I'm not wasting 200ml at a time in a trail jar!
If anyone wants to check out the one I bought, its 24 pound plus shipping http://refractometershop.com/shop/shop.php?action=full&id=257
Good luck. :thumb:

 

[Boneym]

Hi
Interested in your input on refractometer. Any issues with it. Its reduced to 19.99 now i think. I am interested in buying one

 

[whinton]

Hi
Interested in your input on refractometer. Any issues with it. Its reduced to 19.99 now i think. I am interested in buying one

It has been good so far. No problems. One thing to mention though. After purchasing I received an email looking like it was from the refractometer shop asking to confirm my credit card details. I had already received the item and concerned that it was someone up to no good, I got in touch with the shop. They said they would never ask for card confirmation details by email and were looking into what I had forwarded to them.

 

[Noah]

I use a Hydrometer and a Refractometer. I usually use both for the OG and just the Refractometer for the FG. Reason for this is that I get a good comparison at OG stage and by using the Refractometer at the end of fermentation, I'm not wasting 200ml at a time in a trail jar!
If anyone wants to check out the one I bought, its 24 pound plus shipping http://refractometershop.com/shop/shop.php?action=full&id=257
Good luck. :thumb:

Thanks for the info, I usually drink the contents of the trial jar! It's still the same price by the way. The £19.99 is without vat.