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[on:]

I am trying to measuring small objects such as beads and output the weight in grams to an lcd display. What kind of sensor can would I need to do this? 

[Reply #1 on:]

ou could always use a retail scale like this one that measures up to 1 kilogram in tenths of a gram:

 http://www.everydaysource.com/product/mini-1000-x-01-gram-digital-pocket-scale-jewelry-scale/81848?esprcggbadtf130219=sc+gb+81848&utm_source=google&utm_medium=product_search&utm_campaign=google_base&aid=1297&gclid=CPjPvL_dxbUCFULf4AodlnMANw

At $9.39 it's cheaper than an Arduino.

[Reply #2 on:]

If the load cell must be read by the Arduino then see http://cerulean.dk/words/?page_id=42 for an example. It's not too hard to get right; the most problematic part is getting the gain set correctly. You'll want to use some sort of low value trimmer to get it right. Also, you'll be limited by the precision of the Arduino's A/D converter (10 bits) unless you use an external, higher precision A/D converter.

You still need the load cell of course, and extracting it from a scale like John linked is still a good idea.

[Reply #3 on:]

And you will need to calibrate it somehow.
Unless this needs to be part of some larger, automatic machine,  it really is easier to just buy one,  about $10 on ebay.