How do you measure LESS than a gram?

[The Pol]

So, if one is to build his water up from RO, or is to adjust his own water... how do you make these FINE adjustments that call for less than a gram of a certain salt?! I have seen digital scales that measure to ONE gram, but not less.

 

[Vels]

Dissolve in 1 liter (1000g) af water and and 1g solution=1mg solid

Cheers
Jakob

 

[david_42]

There's a scale here that goes down to 0.05 grams.
http://www.sciplus.com/search.cfm/scategory/SCA/term/scale

A standard method is to dissolve the salt in water and portion it out. 1 gm in 100 ml (100 gm) and you've got control down to 0.01 grams. Keep the extra in jars. A little practice with an eyedropper and you can get 20 drops to the ml. That puts you down to 0.5 mg.

 

[Brew-boy]

I use my gun powder scales which weighs in grains and grams very very accurate. I can weigh .01 of a gram. But I dont worry as I round up and never tasted a difference from lets say 1.7gm to 1.8gm of any salt.

 

[jdoiv]

I bought a jewlers scale of ebay that measures out to .01 of a gram. I think is was something like $5 or $10. By the time you calculate out what you need for both your mash and sparge, a little fudging of the salts isn't going to make a difference.

 

[BlendieOfIndie]

You could try to convert the volume of the salt to the weight:

1st measure the weight of a few large amounts:
1/16 cup (1 tbl spoon) = W grams
1/8 cup = X grams
1/4 cup = Y grams
1/2 cup = Z grams

Now find the average of weight per cup: (16W + 8X + 4Y + 2Z) / 4

The more trials you perform the more accurate your estimate will be.

Now that you have the # grams per cup, you should be able to the volume of salt to add to the water. This idea assumes that you have accurate measuring spoons/cups in your kitchen. It also assumes that your small measuring spoons hold less than a gram of salt. That might be two to many assumptions

 

[pjj2ba]

Dissolve in 1 liter (1000g) af water and and 1g solution=1mg solid

Cheers
Jakob

+1 on this. This is really the way to go. If this were something you were going to routinely do. I'd make concentrated stock solutions of the salts you want to add.

Say you want to add 0.25 grams of Calcium Chloride for your 5 gal. batch. First make a stock that is 10 gms in 100 ml of water (1 gm in 10 ml). Now when you are getting your water set up, you simply add 2.5 ml of the stock solution (0.1 gm/ml) and you are set.

You can mess around with how concentrated the stocks are to deal with what weights your scale can handle and what liquid volumes you can accurrately measure.

You could just as easily dissolve the 4 gms of the salt in 1 quart or water (1.0 gms per cup) and then use 1/4 cup of that. Of course the more dilute your stock, the more space it takes up for storage.

 

[EvilTOJ]

I just bought a cocaine scale from South America. Works fine for me, and now I don't have to guesstimate when I measure my blow.

 

[raceskier]

I use a triple beam balance, but admit, that's not a very economic alternative. Somewhere I have one like this: http://www.wellcoolstuff.com/thestore/prods/HS2.html , that I believe measures in 1/4 gram increments. I think I paid something like $1 for it, back in the day. They are tough to find these days, as everyone has gone digital.