Just curious about adding salt ions and scale range.

[Snafu]

Just curious how precise the majority is. If I use Promash or even EZ spreadsheet, the ion additions can get pretty small ie: 1.91 grams of XXX. Are most of y'all using scales that read 1/100 of a gram? Currently I just use a 1g scale. But I'm tossing the idea around of getting a 1/10 or 1/100 grams scale. Anyone want to recommend a scale? I've seen some out there that include a calibration weight. I would think a scale with removable tray would be best, not for measuring on, but cleaning. Most scales have a tare function anyway. What say you?

 

[DeafSmith]

I use an ammo reloading scale made by RCBS. I have the model 1010, but they have another balance beam model that sells for $57.

https://shop.rcbs.com/WebConnect/Ma...=CategoryDisplay&categoryId=C08J154&route=C08

There are a number of these used scales for sale on eBay, so you might be able to pick up one pretty cheaply, especially if you are willing to use a balance beam scale instead of electronic.

http://www.ebay.com/sch/i.html?_nkw=rcbs+reloading+scale

The only problem with these reloading scales is that they weigh in grains, not grams, so you will have to convert (15.4 grains per gram). The one I have has a resolution of 0.1 grain, or 1/154 gram.

 

[Snafu]

Whoa, now you have me thinking. I used to have a set of triple beam scales I used for reloading ammo that weighed in grains, I guess I could dig that out of storage and use that, but I think I'd rather go digital now that I think on it some more, heck, I do enough converting as it is.

 

[ajdelange]

The better the scale the more accurate your weighings, of course but I don't really have a number that says how accurate you ought to be. I've been called an "accuracy freak" both in the lab and at the rifle range so you can probably guess what I use - an analytical balance that reads to 0.1 mg. I use that for experimentation as well as brewing. In no way is that level of accuracy required for measuring out brewing salts.

There are ways to increase accuracy. With a scale that reads to 1 gram precision if you need 2.5 grams of something you have the choice of weighing out salt until the scale reads 2 or 3 and you could clearly be off half a gram or more. In such a case you could weigh out 10 grams of the salt, dissolve in 100 mL of water (measured accurately) and then add 25 mL of the liquid. Or 20 grams in 200 mL etc. The larger the mass of the salt you weigh relative to the scales precision the less error. Salts are cheap.

Scales: I have noticed over the year that many homebrewers like not only to fill glass bottles with beer but little brass bottles with powder and bullets [Edit: and I see you are one of them]. Reloading scales are pretty accurate and relatively inexpensive so I often suggest those. You'll have to convert grains to grams though.

 

[Snafu]

Just did a quick search on ebay, funny how most of the scales that read 0.01 g look like drug paraphernalia (cigarette packs, lighters, ashtrays, medicine boxes) good grief I'm a brewer, not a drug dealer!

 

[Snafu]

0.1 mg?? good lord man! I guess you hold your breath as to not breath on the tray?...lol

 

[ajdelange]

Just did a quick search on ebay, funny how most of the scales that read 0.01 g look like drug paraphernalia (cigarette packs, lighters, ashtrays, medicine boxes) good grief I'm a brewer, not a drug dealer!

I kid thee not I read a book on homebrewing years ago in which the author recommended police auctions as a good place to get used scales.

0.1 mg?? good lord man! I guess you hold your breath as to not breath on the tray?...lol

You can breathe but you cannot move around. The pan is inside a little glass house with sliding doors on top and sides. The balance also sits on a slab of granite (the piece leftover when they cut out the hole for the sink in a granite counter top) which in turn sits on soft rubber feet. Even so you must stand dead still when doing a reading.

 

[mabrungard]

I find that the ability to measure to 0.1 gram is quite accurate enough when dealing with the typical 5 gallon batch amounts.

 

[josephus23]

I have 3 Ohaus triple beam balances thatI'd be happy to sell. They have a max of 310 grams. If your looking digital for sub-gram measurements try the Ohaus Scout or Scout Pro. You can get them for about 30-40 dollars on eBay.

 

[ajf]

I use http://www.americanweigh.com/product_info.php?cPath=24&products_id=290
Works fine, but I have to replace the batteries every year or so.

-a.

 

[michaeltrego]

I recently bought this one on Amazon: American Weigh Signature Series Black AWS-100 Digital Pocket Scale, 100 by 0.01 G by American Weigh $11.79

Looking forward to using it on my Maibock soon...

 

[brushvalleybrewer]

I use a Blade Scale. Resolution of 0.1g. It makes me look like a drug dealer, but it helps me make great beer, so I have learned to deal with it.

 

[Snafu]

I use http://www.americanweigh.com/product_info.php?cPath=24&products_id=290
Works fine, but I have to replace the batteries every year or so.

-a.

I was actually looking at these, does the lid lay flat allowing you to use a tray?

 

[brushvalleybrewer]

Yes.

 

[broadbill]

I find that the ability to measure to 0.1 gram is quite accurate enough when dealing with the typical 5 gallon batch amounts.

bingo....0.1 g accuracy is probably sufficient. Doesn't hurt if you go 0.01 though, I just wouldn't go too far out of my way for it.

 

[DSmith]

I was actually looking at these, does the lid lay flat allowing you to use a tray?

The lid doesn't come off. I cut-up a few sheets of paper and store them in the scale lid for measuring on.

http://www.americanweigh.com/product_info.php?cPath=24&products_id=290

This scale is great for treating water and measuring hops. It's less than $12 on Amazon. It has a "floating zero" so if you start out with the scale tared to 0 you need to put at least 0.03 gm on the scale to prevent it from self-adjusting back to 0. I generally put a piece of paper and not tare the scale, then start weighing.

A campton tablet weights about 0.65 gm and treats 20 gallons. I dillute my tap water with >75% RO/distilled water and commonly measure <0.1 gm of a crushed tablet to treat the tap water for chlorine. I also dechlorinate my cleaning and sanitizing solutions at the same to make the best use of a single tablet.

 

[Snafu]

I went with this one also got 2 100g calibration weights. I won't have it for this weekends brew, but should be here next week for my next brew. I'll just wing it this weekend. Always done that in the past anyway.

 

[adamreef]

Sorry Sgafu, I am a little late. Maybe could have saved you some $$. Anyway, for anyone looking at this in the future, a very good solution to this problem is to make stock solutions.

Depending on the salt, you can dissolve (pulled out of the air for the sake of an example) 100 grams of a particular salt in a 1L bottle of water. This will give you .1g/ml. It is quite easy to measure 1/10 ml with a small syringe, allowing you to accurately add the salt in .01g increments. 100 grams is about 3.6 ounces which is solidly in the comfort range of whatever scale most of us use for hops.

There are some limitations to this. For example, CaCO3 is very poorly soluble so it is hard to make a solution concentrated enough to be practical. Also, MgCl2 and MgSO4 are both highly hygroscopic (attract water), so when you may be weighing a significant amount of water when you weigh them.

Hmm... maybe this would make a good article to post. May have to work on that.

Hope this helps.

Adam

 

[ajdelange]

Anyway, for anyone looking at this in the future, a very good solution to this problem is to make stock solutions.

I agree. See #4.

For example, CaCO3 is very poorly soluble so it is hard to make a solution concentrated enough to be practical.

Not a problem. Make a suspension. Just be sure to vigorously shake it up just before you pour off the liquid you are going to add. You should seldom need calcium carbonate.

Also, MgCl2 and MgSO4 are both highly hygroscopic (attract water), so when you may be weighing a significant amount of water when you weigh them.

Calcium chloride, yes. It will, in any of its forms, continue to attract water from the air to the point where the originally solid salt turns to soup. Most people obtain MgSO4 as the heptahydrate which is pretty stable.

In any case, this is a potential problem regardless of the accuracy of your scales. There are ways around it which are standard laboratory practice (heat in an over at 103 °C for a few hours, cool in a dessicator) but given the level of accuracy required in home brewing it is not necessary to go through this unless you are doing analysis.

 

[Snafu]

FWIW, got new scale in today. Seems to be working just fine. Reads in g's the auto off isn't fast at all. Good for slow pokes like me. And as long as I don't breath on it, it doesn't wander around at all. Seems balls on when reading the calibration weights I ordered.