L. P. Skeen on fri 9 dec 05
think?
Hey Mike,
I have found the digital scales to not be very accurate when weighing small
quantities. YMMV. I bought an Ohaus 10lb digital scale some years ago, and
even though it is suppsoed to be accurate to 1g, that doesn't mean that only
1g will actually register on the scale. You should get a weight or
something you KNOW for sure weighs 1g and test the scale. The triple beam
balance takes one glaze mixing session to learn how to use correctly, and it
is so sensitive you could sprinkle baby powder on and it would move. I
prefer the triple beam. The only brand I've ever seen is Ohaus.
L
L
----- Original Message -----
From: "Mike Juengling"
To:
Sent: Friday, December 09, 2005 8:36 AM
Subject: Re: triple beam scales vs. digital scales... what do you all think?
> think it was a great purchase. It has a capacity of 5lbs or 2.2kg and is
> accurate to .1 oz or 1 gram.
Linda Ferzoco on fri 9 dec 05
think?
When you purchase a balance, there are a couple of key values to look for: the range of weights that can be weighed and the accuracy of the instrument, which is usually expressed as a plus/minus figure. E.g. a balance will weigh up to 1000g or 1 kg, with an accuracy of +/- 1 g. That means that when the balance reports that something weighs 500g, it might truly weigh anything from 499.5 to 500.5 grams. That's just fine when you're weighing larger quantities
However, when you need to weigh small amount, say of 50-100 grams or less, you will need a balance with a lower range and comensurate accuracy, say a 100 gram balance with +/- 0.1g of variance.
Neither a triple beam balance or the digital will work accurately and precisely unless one does two things: levels the balance and keep in clean.
Typically, our balances are in a very dusty environment and I've never seen anyone but another former lab rat check that the balance is level. So please, whichever equipment you get, level it before use and keep it dust-free as much as possible. Dust will mess up the digital much more that that trusty ol' Ohaus triple beam. Of course, if you don't calibrate either, fagettaboutit!
Falling off her high horse,
Linda Ferzoco
California
Mike Juengling on fri 9 dec 05
think?
Hey L, I haven't checked it against a known standard so I can't say if =
it
would be acceptable equipment at the National Bureau of Standards. I =
have
had the same experience as you are describing as to it's sensitivity. =
i.e.
it seems to register extremely small changes. Also it is consistent in =
it's
readings. I had occasion to mix a large batch of glaze (for me). I =
measured
the ingredients into a single container. Then I emptied the container =
part
by part and weighed them each individually. The sum of what I put in
equaled the sum of what I later took out -exactly. The 'you get what =
you
pay for' philosophy is not always true. The Ohaus seems to have a good
reputation among potters from what I have seen and read. However I would =
be
very surprised if it would make any difference if I used it instead of =
my
current scale.=20
-Mike
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of L. P. Skeen
Sent: Friday, December 09, 2005 10:00 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: triple beam scales vs. digital scales... what do you all =
think?
Hey Mike,
I have found the digital scales to not be very accurate when weighing =
small
quantities. YMMV. I bought an Ohaus 10lb digital scale some years ago, =
and
even though it is suppsoed to be accurate to 1g, that doesn't mean that =
only
1g will actually register on the scale. You should get a weight =
or
something you KNOW for sure weighs 1g and test the scale. The triple =
beam
balance takes one glaze mixing session to learn how to use correctly, =
and it
is so sensitive you could sprinkle baby powder on and it would move. I
prefer the triple beam. The only brand I've ever seen is Ohaus.
L
L
----- Original Message -----
From: "Mike Juengling"
To:
Sent: Friday, December 09, 2005 8:36 AM
Subject: Re: triple beam scales vs. digital scales... what do you all =
think?
> think it was a great purchase. It has a capacity of 5lbs or 2.2kg and =
is
> accurate to .1 oz or 1 gram.
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