Small Weights Scale

I have three small digital scales, and they have a reasonable margin of error down to around .25 ounces. Maybe even .125. at 1/8 oz I double check across all three because sometimes one or another feels a little "sticky". I can't really justify the cost of a high end lab scale for as often as I need to weight smaller objects, but I sometimes do need to weigh small objects. Today down to .015625. 1/64th of an ounce. Two of my scales round to the hundredth, and most of the time that's "good enough." On these they both read .02. That's a huge margin of error. The third scale that gives resolution to the thousandth didn't even register the object in normal mode. Not surprisingly it is the cheapest of the three.

I'm looking for something I can keep in my desk when I am doing design and reverse engineering work to verify those small weights.

Yes this is metalworking related.

Reply to
Bob La Londe
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Look on ebay. There are all sorts of scales that read to 1 tenth of a gram, with an accuracy of perhaps + or- 1/2 a tenth. And a tenth of a gram is 1/280 ounce. I recently bought a couple electronic scales and one reads to .01 gram. And repeats within less than .01 gram. I have another scale that reads to .001 gram with an accurace of + or - .001 gram. It's fun to weigh a small piece of paper, tare the scale, make a short mark with a ball point pen or a pencil, and then weigh the mark. I test the scales with precision Ohaus weights. These scales are remarkably cheap and accurate. Eric

Reply to
etpm

You're in luck. I've got an old Ohaus that does tenths of a gram, and a set of calibration weights to test it, but it's mainly just gathering dust because kitchen scales are SO good nowadays.

Taylor makes a glass-plate thing

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that's accurate to a tenth of a gram (that's under a hundredth ounce), and there's other brands just about the same performance.

Reply to
whit3rd

I bit on one of these awhile back to weigh airgun pellets and such:

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Reviews for it were okay at the time. I've only used it a few times, it worked okay. Figured I wouldn't be out much $$ if it failed...

Reply to
Leon Fisk

Bob La Londe snipped-for-privacy@none.com on Fri, 30 Aug 2019 15:31:49 -0700 typed in rec.crafts.metalworking the following:

There was a saying back when clocks were a new fangled technology, that if a man had one clock, he knew what time it was. But if he had two, he could not be sure. (Some early clocks were +/- fifteen minutes a day.) Same applies here: you have too many scales. B-) Not to mention, you do not have one which is accurate "enough". Bite the bullet, and buy one which will work for you. Which reminds me of the time my friend was considering the purchase of a yard debris shredder. I asked him "how often have you needed one?" He replied "Not often, but if I had one, I would be using it more often." So, in all likelihood, you will discover that being able to measure to the 1/64th oz (or better) will become one of those things you do more often. Because you have the scale "right over there."

Reply to
pyotr filipivich

Harbor freight had a scale with a maximum of 1 lb/500 grams. It read to 0.1 grams and was quite handy. Their new version is nearly worthless, however. If you put a cup on that scale & add a fluid slowly, the scale won't show it! Programmer probably viewed slow changes as electrical noise.

Hul

Bob La L> I have three small digital scales, and they have a reasonable margin of

Reply to
Hul Tytus

It suffers from the boiled frog syndrome.

My tiny chiwanese 300g scale has a .01g accuracy and has seemed to retain accuracy. It will react to small increases as I have tried it with powdered (legal) herbs and spices when making Garam Masala. Similar to this $6 Chiwan model on Ebay:

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Reply to
Larry Jaques

Scales are incredibly cheap and decently accurate nowadays and amazon is full of them. There is probably many more brands than actual manufacturers, as is often the case with imported products.

i
Reply to
Ignoramus21008

Yeah, I was over thinking the whole thing. Just ordered a "jewelry scale" that claims resolution of 0.001oz or 0.01g for ten whole smackers. If its no good I can send it back on Amazon's dime. I already have a set of calibration weights so I can check it.

Reply to
Bob La Londe

O.K. I've got a cheap Harbor Freight digital scale, one of two they offer -- the other is for postal purposes.

This one can read lbs, oz, or gm (with the gm being the highest resolution). It can only read down to 1 gm, which translates to

0.035273962 oz, so not quite good enough for your purposes.

For your purposes, a beam balance (inexpensive classroom lab scale) with a sliding weight covering the range from 0 to 10 gm.

My example is marked "Ohaus Harvard Trip Balance", and I got it at a hamfest maybe a decade ago or so. It is an example of the "Triple Beam Balance" Some of them have several sliding weights so you don't need the separate set of weights. Just slide the weights and add the readings to get your final value. There is an example of one in eBay auction # 362760119741 -- and many others.

If you want to weigh things above 10 gm, you also need a set of weights to put on one pan, while what you are weighing is on the other. Once you get it close (almost heavier on the weight side) you then use the sliding weight to get it down to 0.1 gm.

Looking at the two-pan balance (like mine), there are a number of the "Ohaus Harvard Trip Balance" on eBay -- *new* and around $300.00, so not the ones to play with. But they are examples with a second beam and sliding weight, so it can go up to 2000 gm without external weight sets.

There are also a bunch of Ohaus made toy balances -- plastic parts, and bright colors for kids, which are not worth considering for your purposes. :-)

Also from another hamfest is a really nice one made by Mettler, which directly weighs from 159 gm down to 10 mg (0.010 gm), which is

2.2857143e-05 oz. (0.000022857143 oz). This might be more difficult to find -- and especially to find for a reasonable price. It is a single pan balance, working with a number of ring-shaped weights lifted clear or put down by knobs on the front panel. It has sliding glass doors to keep breezes from disturbing the pan. And it has a projected light scale on a ground-glass screen to tell when it is in balance as you work the knobs. The main thing you need to do when you set it up is to dust off the hanging pan, then set the knobs to zero, and adjust an extra knob to zero it with nothing there to weigh. There is a lever on the left hand side about half-way back which will limit the travel so it won't be damages by bouncing around -- or with too much weight applied to the pan too quickly. Put the thing to be weighed in the pan, then operate the lever to gently let the pan bottom before you start to balance it. You can see the lever/knob in the view from the left hand side.

Oh yes -- also when you first get it -- take the top off and make sure that the ring weights are centered so they are properly lifted by the knobs. There are different sizes of concentric weights which are added by the knobs to give the right display.

I find one on eBay -- for $65.00 at the moment. eBay auction # 202723286908

Or you could use a reloading scale, but beware, that is measuring in grains, not grams. 1 grain (gr) is 0.0022857143 oz, or

0.06479891 gm (grams).
Reply to
DoN. Nichols

I ordered on MVZAWIND X001RHV22V off of Amazon. It was as cheap as my Harbor Freight scales or darn close. My calibration weights show it at dead on at 5 grams (the smallest calibration weight I have). I weighed some items that "reportedly" run around 1/64 oz and it registered them at .016 for nine out of ten units with a rare few registering at .015. That's close enough for what I am doing.

The best part is that it does not seem to suffer from boiling frog syndrome. I was able to add much lighter objects and consistently get stack up readings +/- .002 or better.

I keep it in its pouch, in the clam shell, in the box, and ONLY take it out for those times when I needed it. The rest of the time I use my Harbor Fright scales. I've needed it twice since I bought it.

When weighing multiple items and removing them I noticed zero drifted a couple thousandths. Rezero each time and the weights were consistent. At .001 resolution I imagine just very little dust or a detritus can make a difference.

Reply to
Bob La Londe

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