Page 1 of 1

Digital Scales for measuring hops/specialty grains

Posted: Wednesday Feb 28, 2007 11:09 pm
by Ash
So guys, what's out there that's affordable?

Jaycar have a upto 200gm scale with a 0.2g resolution for $40 or so - but I figure a bit more headroom with maybe a 0.5 resolution would be better but I've only seen 1-2kg with 1 or 2 gram resolution ones for similar money, nothing that bit bigger with a fine resolution

Am I just being too picky here?

Posted: Wednesday Feb 28, 2007 11:13 pm
by Rysa
Ebay?

Posted: Thursday Mar 01, 2007 8:15 am
by Pale_Ale
I've got a set of kitchen scales from Big W. 1g Res. Got it on sale for $15 or so...I would look at the dept. stores first. I use this to measure all my hops, malt and spec grain. Works a treat!

Posted: Thursday Mar 01, 2007 8:44 am
by rwh
I have the same as Pale. Any more than 1g accuracy and the price seems to skyrocket.

Posted: Thursday Mar 01, 2007 9:40 am
by drsmurto
same here. mine is up to 5kg with a 1g accuracy, does ounces/pounds as well if you swing that way... $26 from kmart.

Ebay - cheap scales but the postage generally brings it back to the dept store prices...

Posted: Thursday Mar 01, 2007 2:00 pm
by SpillsMostOfIt
For hops, I have a set of digital jewellers' scales that measure 0-100 grams with 0.01g accuracy. I use them for hops, Irish Moss (and lichens) and the normal kitchen scales for the other stuff. The grain I buy has already been measured by several people.

The digital scales came in useful yesterday as I was calibrating a new '20 litre' jerry can. No two things with volume markings on them agree in my house, so I decided to get to the bottom of things.

I took the 100g calibration weights and calibrated the 2kg kitchen scales. I then measured 1kg water and used that to calibrate the most accurate device I had (a Brita water filter - the pyrex jugs are way out). I then calibrated my jerry can one litre at a time. At 20 and 24 litres (the capacity of the 20 litre jerry), I checked my Bunnings fermenter. I then checked my FB boiler at 20 and 24 litres.

It was a complete pain in the gluteous.

Posted: Thursday Mar 01, 2007 2:06 pm
by KEG
so how inaccurate were they? was it worth the effort? i.e more than 3 or 4% different? i doubt any taste difference would be noticable at that or less..

Posted: Thursday Mar 01, 2007 6:32 pm
by SpillsMostOfIt
KEG wrote:so how inaccurate were they? was it worth the effort? i.e more than 3 or 4% different? i doubt any taste difference would be noticable at that or less..
Ignoring any error, the kitchen scales have 10gram gradations, so (according to one of my university lecturers of - gosh - 24 years ago) you can only claim 5gram precision. For hops (particularly high alpha), that could make the difference between good and not so good beer. At 1kg, that would be 0.5%, but I rarely use a kilogram of hops. Conversely, I could not weigh five grams of hops with them, or - because of the way *I* work - any amount of hops that I am going to use for a normal-sized batch of beer.

As it happens, it would seem that their accuracy was in line with their precision. I am comfortable that I now have a set of calibrated equipment (boiler, no-chill cubes, fermenters, etc). In one sense, it doesn't matter, because I have them calibrated against each other and so long as I don't try to subject other brewers to my recipes, it will be internally consistent and so workable.

Why did I do it? I am trying to remove as many variables from my process as I can. I figure that error in much of this game compounds, so if I can remove as much as I can, I will be better off. I also want to have it within coo-ee of reality, so the actual values are important to me. This may or may not work for others, but we are talking about *me* here, so expect some weirdness... :wink:

Posted: Thursday Mar 01, 2007 7:09 pm
by Pale_Ale
Is it possible that conventional kitchen scales have progressed in the last 24 years?

Mine seems to be accurate and I have not had a reason to doubt their accuracy. I have even weighed bags of hops from HB stores and they have checked out against what they listed the weight as being (allowing for packaging)

Posted: Thursday Mar 01, 2007 7:51 pm
by SpillsMostOfIt
Pale_Ale wrote:Is it possible that conventional kitchen scales have progressed in the last 24 years?

Mine seems to be accurate and I have not had a reason to doubt their accuracy. I have even weighed bags of hops from HB stores and they have checked out against what they listed the weight as being (allowing for packaging)
It is my university education that has aged by 24 years - not my kitchen scales.

In what quantities do you add hops? I buy my hops in quantities between 90 and 450 grams and use them in quantities as low as 5 grams (or uneven quantities thereof). Also, I am me and don't necessarily recommend doing things the way I do... :wink:

Posted: Thursday Mar 01, 2007 8:56 pm
by Pale_Ale
SpillsMostOfIt wrote:It is my university education that has aged by 24 years - not my kitchen scales.

In what quantities do you add hops? I buy my hops in quantities between 90 and 450 grams and use them in quantities as low as 5 grams (or uneven quantities thereof). Also, I am me and don't necessarily recommend doing things the way I do... :wink:
I'm suggesting that at the time the advice was given, i.e 24 years ago as indicated in your email, that kitchen scales in general were of a lower quality - i.e most people did not use digital scales in their kitchen in the early 80s! :P

I generally weigh hops out from between 5 - 20g and purchase hops in a as low as 50g bags.

Posted: Friday Mar 02, 2007 7:10 am
by SpillsMostOfIt
Pale_Ale wrote:
SpillsMostOfIt wrote:It is my university education that has aged by 24 years - not my kitchen scales.

In what quantities do you add hops? I buy my hops in quantities between 90 and 450 grams and use them in quantities as low as 5 grams (or uneven quantities thereof). Also, I am me and don't necessarily recommend doing things the way I do... :wink:
I'm suggesting that at the time the advice was given, i.e 24 years ago as indicated in your email, that kitchen scales in general were of a lower quality - i.e most people did not use digital scales in their kitchen in the early 80s! :P

I generally weigh hops out from between 5 - 20g and purchase hops in a as low as 50g bags.
I've re-read this a couple of times wondering why the disconnect, then I realised...

My kitchen scales are not digital - my jewellers' scales are. My kitchen scales are a funky French design to look at but are just a spring and rotary dial thing.

I was taught that when reading a graduated scale (as opposed to scales), I can only split a graduation in half - I cannot (even though I may be tempted) estimate a third or a 16th of a graduation repeatably, so if the scale is marked in grams, I can only estimate one-half of a gram. It is probably the one thing I recall about observational error.

Hop alpha acid ratings probably vary heaps from what is marked on the pack and degrade over time. I have no control over that.

I figure that by focusing on those things I can control I will reduce the total error in my *cough* system...

Posted: Friday Mar 02, 2007 12:14 pm
by Crowash
Wow.... I measure 20g of hops by putting a little less that half a 50g packet in. You don't want to see me meausuring the water to go in the fermenter :shock: I reckon the amount of liquid in the fermenter would alter by close to a litre depending on how level I hold out the measuring cylinder while I point the hose at it.

Posted: Friday Mar 02, 2007 8:14 pm
by Pale_Ale
I think when all is said and done digital kitchen scales are reliable enough for weighing out hops etc. I wouldn't use the normal type.

Posted: Friday Mar 02, 2007 9:27 pm
by derfly
Crowash,

Yep, TLAR method ........ that looks about right :wink: