New digital scale, gotta laugh

[Paper_Zombie]

I post quite a bit in Rifle Country, but this is my first in the reloading forum.

I'm barely sticking my toes in, still waiting on a couple things to arrive, and getting frustrated at the difficulty in finding components...but I did get my new scale, which measures in many things, including grains, and I thought something was kind of hilarious.

It's a Puri-test "DigiWeigh" I bought off amazon for about $25. It came pre-packed with a 100 gram calibrating weight...

but, I guess the company it shipped through is some kind of archery supply, and they gave me a "free" (get this) really fancy -gold plated- 5-gram calibration weight.

It's all shiny and fancy and pretty, with ".999 gold plated" stamped right on it...

And it's also about 1/2 gram shy of what it should be. I figured this because the 100 gram weight reads dead on, at 99.99, and I dug a nickel out of my pocket and it read at 4.94 (it's a worn nickel).

Why go through the bother of making this awesome looking little gold bar if it's not even correct? LMAO

P.S. Overall, happy with the scale though. Has a lot of options, just a tad slow. Gotta take it easy and give it a sec. or two when adding powder.

 

[ironworkerwill]

I thought of how cheaply made the lee scale was when I first received it. Now it's an important part of my process. And I have come to like it's simplicity.

 

[col.lemat]

It is gold plated for a reason. Also you should not pick it up with your bare hands.

 

[Paper_Zombie]

Please enlighten me.

You should know, I am very familiar with handling precious metals, as I am also a coin collector. The weight was only touched by it's edges. Are you saying my skin-oil subtracted 1/2 gram?

When two out of three weights are correct, I'm inclined to believe the majority.

 

[col.lemat]

No . The sweat and dirt from your fingers will add to the weighting, also cause rust if not gold plated. In the mines we weighed the gold and the ballance weights were never touched by hands. I got a royal azz chewing for doing it as a newbe. Do it once and you will never make the mistake again. When you get a powder scale the pan will be gold plated also (prevents oxidation). Mine weighs 1/10 grain

 

[Paper_Zombie]

No . The sweat and dirt from your fingers will add to the weighting, also cause rust if not gold plated. In the mines we weighed the gold and the ballance weights were never touched by hands. I got a royal azz chewing for doing it as a newbe. Do it once and you will never make the mistake again. When you get a powder scale the pan will be gold plated also (prevents oxidation). Mine weighs 1/10 grain

Granted...with time.

However, with hands freshly washed, I'm not worried about adding to the weight.

You seem to have missed that it was -under- weight, not over. I thought it was funny, is all. An american nickel has a known weight, and I'm willing to accept that the .06 difference is due to the "wear and tear" on a modern nickel.

As a machinist, I find it amusing that they would bother gold-plating a weight-standard that isn't within spec. I used to grind height-standards that would be scrapped if they were out of tolerance by .0002".

 

[ljnowell]

I bought a 20 something dollar scale off amazon one time, supposed to be .1gr resolution. Found out once I got it that it was .2gr. Pretty worthless for reloading, IMO, unless you are just double checking that you dont have a gross over/under situation.

 

[Lost Sheep]

It is gold plated for a reason. Also you should not pick it up with your bare hands.

Correct. Gold does not tarnish or oxidize and generally protects whatever it is plated on.

But (in my opinion) the "Gold Standard" is gravity. At anything not close to the the speed of light, the force applied on a given mass by gravity is pretty reliable. The voltages applied by batteries may vary and the voltages supplied by power companies though their transformers and transmission lines which are not tuned to laboratory standards are just "good enough" for household appliances. But not for the accuracy required for accurate measurements.

The more expensive electronic measures are regulated to allow for the vagaries of commercial power and dry cell batteries, but I would not count on a $30 measure to be there.

Gravity. It has gravitas.

I do have an electronic measure. It is accurate enough. But I check my powder charges (and all things that can injure me) on my balance bean scale.

Lost Sheep

p.s. (while I was composing, more posts came in).

No . The sweat and dirt from your fingers will add to the weighting, also cause rust if not gold plated.

Are you saying my skin-oil subtracted 1/2 gram?

That seems odd to me, too. But how do you determine if your brand-new scale is off or if your check-weight is off? Have you got another check-weight available or another collector who has a scale of known accuracy that could resolve your question?

Lost Sheep

 

[col.lemat]

I can't explain the under weight, but now you know why the gold plateing. Always good to have several checks in the process

 

[col.lemat]

Yuur name is good as gold, as the saying goes. I have seen gold scales that would weigh the ink left on paper in a persons name. Some pepole weigh fly turds also I would guess.

 

[Paper_Zombie]

But (in my opinion) the "Gold Standard" is gravity. At anything not close to the the speed of light, the force applied on a given mass by gravity is pretty reliable.

Haha...I LOVE that! I also happen to be a sci-fi enthusiast. And while it may not be totally relevant to reloading, I'm feeling warm and fuzzy that someone even -mentioned- the speed of light. So, how do you manage to measure that on a digital scale? (So many things to consider when measuring specific gravity)

That seems odd to me, too. But how do you determine if your brand-new scale is off or if your check-weight is off? Have you got another check-weight available or another collector who has a scale of known accuracy that could resolve your question?

Lost Sheep

Ah, well as I said, I had three "known" weights. If the pretty one is to be believed, it would mean that the other two are false. Whereas, if I assume TWO out of THREE "known" weights are correct, I can also assume that the pretty gold-plated one is wrong/inaccurate/misleading.

That's my logic speaking, at any rate.

 

[chris in va]

My head hurts. Thank you Sheldon.

 

[Paper_Zombie]

My head hurts. Thank you Sheldon.

You're welcome, Raj.

 

[kingmt]

Well the scale could be off at that range check the weight in all four corners(if it has corners) or for points. It should be the same at each point. If not the scale is bad. If it is have your check weight tested on another scale.

 

[rfwobbly]

Mr Zombie -
With all due respect, both weights are rather meaningless for your job. You want to zero any scale in the range in which you load. The 5 gram weight is equal to 77 grains. Unless you are loading powder in the 70-90 grain range, then a 77 gr check weight means very little.

The reason for this is that a digital scale has so many ways to be "off" (friction, temperature, power source, magnetic fields, etc), and all those issues overlap. So a digital scale may 'read high' at the lower end due to friction, and at the same time 'read low' at the upper end for another reason. Additionally, over time effects of friction or temperature may be more or less of an issue. So if you are looking to weigh in the 30 grain range, you therefore need a 30-35 gr check weight.

If you don't follow what I'm saying, then go "zero" your bathroom scale with the 100 gram (0.22 pounds) weight. Your wife will either instantly gain or loose 35 pounds, and her mood will change accordingly.

Bottom line is that you'll need to buy a set of digital scale check weights so that you can be sure that your scale is accurate in the range you're using it. SUCH AS THESE

 

[FROGO207]

My cheapo digital scale is used for gross weight sorting of bullets and as an example at reloading classes not to waste your money on one. YMMV
BTW I have two Ohaus 10-10 balance scales that I use all the time.

 

[kingmt]

FYI gn =grain

 

[jp9mm]

No . The sweat and dirt from your fingers will add to the weighting

I doubt that 25$ scale would pick any change in weight even if you had 100 people touch it

 

[jcwit]

When you have a scale that can weigh the energy from a sun beam you then have an accurate scale!

 

[John3921]

There are a lot of these 0.1 gram scales out there. Problem for reloaders is 0.1 gram is 1.54 grains. We normally want to use an accuracy of 0.1 grains. You need a gram scale capable of 0.01 grams to accomplish something near that. Then you have to convince yourself you can do the conversions without making any errors (bad idea, IMHO).

Then you have to think about rounding. If your scale is good to .1 grams, then 4.95 grams will be 5, and 5.049 grams will be 5. so your .1 gram scale is only getting your load to +/- 0.77 grains. Pretty much useless for powder, maybe ok for sorting brass.

 

[kingmt]

Most of the scales that will do g will do gn so if it is +/- .01g then consider it +/- .2gn which isn't great but close enough. Add long as it read the same every time.

 

[dragon813gt]

As far as using a full set of check weights, you should have a set. But the electronics also come with set instructions on how to zero them. And you need to follow them. If it's a 100 gram scale it's usually in the order of 0/50/100/0. After this process you can then check the full range. But since most of the scales aren't adjustable you're stuck if the weights in between don't match.


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[blkbrd666]

This thread reminds me of My Cousin Vinny...modified for the occasion...

Monalisa Vito: "Because I used a Craftsman model 1019 Laboratory Edition Signature Series calibrating weight. The kind used by Caltech high energy physicists. And NASA engineers."

Vinny Gambini: "Well, in that case, how can you be sure THAT's accurate?"

Monalisa Vito: "Because a split second before the calibrating weight was used to calibrate the scale, it had been tested by top members of the state AND federal Department of Weights and Measures... to be dead on balls accurate!"

 

[splattergun]

There is measure in all things.
Horace, Satires, Bk 1