Can someone please tell me how to calibrate these the most precise way? I can't seem to get it right. What my coins weigh are off around .11 of a gram. I may be saying that wrong but I included pictures. I'm weighing a 1980 penny which should weigh 3.11 grams. My scales show 3.0 grams
A new nickel will be 5 grams. Maybe 1 out of 20 will be over or under, slightly I’m from 1949 and very worn
What do numismatics use to calibrate their scales? I'm sure most have a lot better set of scales vs. my convenience store set. So hypothetically if we all owned this type of scale, what would we use to calibrate it?
It looks to me like that scale isn't designed to weigh more closely than a tenth of a gram. That's not really good enough for work with coins. When you put ten copper cents on it, does it register 30.0, 31.1, or something else?
US nickels are 5 grams, by statute, since 1866. Very rarely over 5.3 or under 4.7 Your scales are off
Does your scale have a grains setting? Use that and then just convert to grams. You'll get a more precise reading than a grams setting which rounds off to one significant digit. Second, get a copy of the mint's allowable weight tolerances for each issue. I've seen a link to it here on CT but I didn't save the link. Maybe someone here can direct you to it. Third, do you have the calibration weight that came with the scale? Are you using it according to the directions? If you don't have a calibration weight, the you need to get one or get another scale. I use this one which I bought off Amazon for about $14 a couple of years ago. It works fine and I've never had occasion to doubt it. That's a 50 gram calibration weight that came with it.
This is worth a try, but it's likely that the scale's resolution just isn't high enough. One grain is around 1/15 of a gram, so not much better than 1/10 of a gram. I've seen that chart too, but it has known inaccurate information for the weights of some issues, so I don't feel like we can trust its tolerance information. Yeah, I still think what this scale needs is a new scale.
Oh, absolutely. But I just didn't want to get into the whole accuracy vs. precision discussion. You know, my calculator will give me six digits but only two of them have any meaning, that kind of thing. Since I don't know anything about the OP's scale, I thought I'd offer an avenue for the OP's exploration of their device.
The scale states to calibrate it I need 500 grams. I tried a jar of peanut butter, which weighs 497g, I might be mistaken on that exact number but it was very close. What else can I use to get precisely 500g?
A hundred fairly-new nickels is probably easiest, but that's definitely the wrong scale for weighing individual coins. I'd say don't knock yourself out trying to calibrate it. Even after calibration, I'd be surprised if it got much closer than 5% accuracy on single coins.
Scales and Balances and all other various named weighing devices should come with a "reference" or "calibration" weight and instructions how to do it so "0" is really zero and .4 grams doesn't show .3 grams or .5 grams due to calibration error range. Drop the scale on a surface, be sure to re-calibrate The ones with x.000 grams devices are more than accurate for coins as a variation is in the mint variations of known ranges. If you are doing diamond , ruby, etc. gemstones cutting, A 0.0000 is desired. My old college has one that goes to 5 zeroes after the decimal for certain chemicals and outcomes, but it is in the 20,000+ range. 500 grams is approx. a US pound. Such a scale is designed for peaches, not coins or precious metals. IMO, Jim
My balance that I use calls for a 200 g weight. I made my own by taking a bottle and carefully adding NaCl to it until it weighed 200.0001 g on a scientific balance. I sealed it and have it somewhere. That 500 g of peanut butter should be in a jar, it has some weight too. Get yourself a balance that weighs +/- 0.01 g.
You need a different scale, one more appropriately sized for coins. For example, the US $20 gold coin is roughly 33 grams. Most scales for jewelry are sized for 50 grams so they are just about perfect for almost all coinage. I suppose some big medals would be too heavy for a 50g scale but that's probably an outlier for what you're doing. I just did a quick search on Amazon for "jewelry scales" and found dozens of offerings for 50 gram scales in the $14 to $25 range. Pick one and your problems are solved.
When I was looking for a milligram (0.001g) scale, there were lots and lots with 30-gram capacity, which of course wasn't enough for one-troy-ounce coins. I found one with a 50-gram capacity, and I think they're more common now. But I've used my 0.01g scale a lot more; it's usually good enough.
is it a small scale like mine? I guess what I should ask is...is it a scale I can purchase at a smoke shop? That's where I bought the one I have.