Brain&Force
Hazard to Lanthanides
Posts: 1302
Registered: 13-11-2013
Location: UW-Madison
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Mood: Incommensurately modulated
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Accuracy and calibration of cheap eBay balances
So I got some cash for my birthday and I'd like to invest in a few interesting chemicals - but first I need to get a balance! I've been eyeing my
chemicals for way, way too long.
I'm considering getting a cheap eBay balance to do some interesting chemistry with lanthanide malates and ascorbates (as well as some stearates if
available - I want terbium fluorescent soaps to be a thing  ) However, I'm going
to be working with pretty small amounts (<1 gram) and I want to be able to get accurate masses, especially with small amounts of material. I'd like
to find a balance that goes up to 100 grams to milligram accuracy but the get pretty expensive. I found this 10 gram/milligram balance, but I'm not sure if that maximum mass will be too low. Are these balances accurate enough for general use in the
amateur lab, and are there generally ways to calibrate them, even if they say they "self-calibrate?"
At the end of the day, simulating atoms doesn't beat working with the real things...
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Sulaiman
International Hazard
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Registered: 8-2-2015
Location: 3rd rock from the sun
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there is a topic on this somewhere here,
summary ....
. the last digit is usually within 2 digits accuracy, commonly +/- 1 digit.
e.g. 10g x 0.001g scale may be in error by up to 0.002g,
which is more than good enough for amateur chemistry.
You DO need a calibration weight as factory shipped calibration is unreliable.
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careysub
International Hazard
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Registered: 4-8-2014
Location: Coastal Sage Scrub Biome
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Mood: Lowest quantum state
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This one:
http://www.sciencemadness.org/talk/viewthread.php?tid=38823
The Gemini 20 balance is a 20x0.001 g balance available for $25 on Amazon. I have one and it is accurate too about 1 mg using some small test weights
I have (the balance ships with a test weight as well).
[Edited on 23-7-2015 by careysub]
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