Anyone else have problems with electronic scales?

[Pulp]

I have a Cabela's scale. I've never really trusted it because when I trickle in say 40 grains, then put the powder into a case and put the pan back on the scale it will often read 0.2 or more grains, either positive or negative. I can hit the tare button and go back to zero, but then I worry, was it off when I measured the powder or off when I put the pan back on. The other night I zeroed the scale, then dumped powder from a case back onto it and it read 40.7. A 0.7 grain error is WAY too much. So it's back to the RCBS balance scale for now.

Do all scales do this, or should I have spent more money and bought a more expensive electronic scale?

 

[HiredHand]

I think most electronic scales can be finicky. I'm not sure spending more money is the solution because there are a variety of factors that influence a scales readings.

 

[angsniper]

I use a Hornady powder dispenser and scale. So far it has always been right on every time I verify it with the rcbs 505. I verify 1 charge every time I load a batch.

 

[alank2]

Hi,

My digital scale does better on battery power than wall power for some reason.

With a digital you have to understand how the underlying hardware works. It uses a load cell to determine weight. Load cells constantly wander up and down due to voltage fluctuations, temperature, etc. Most digital scales deal with this wandering by having a "zero mode". On my scale it shows a little "-0-" in the upper left of the display. This is the scale tell you that it considers the platen to be empty and if the load cell wanders up or down a little bit, it will keep updating itself to zero with whatever the load cell value is. Most digital scales for example can't read 0.1 grains. If you have tiny pieces of paper 1/4" x 1/4" that weight about 0.1 grains and put them on the scale while it is in zero mode, it will adjust to the new weight and still think it is on zero. Add 5 of these 1 at a time giving it time to adjust to the new zero and it will still be on zero at the end even though it has 0.5 grains on the platen. Remove them all at once and it will read -0.5 grains.

Adding a weight to be measured should be done quickly because once it determines a weight has been added, it keeps the last load cell value (before the weight was added) as zero. It then subtracts the new load cell value from the recorded "zero" one and determines your weight. As long as it is NOT on zero, it will possibly become more inaccurate. This is because the load cell will still wander except now that with something on the platen it is no longer autozeroing.

So, to deal with a digital scale you need to be aware of when it thinks it is and is not on zero. To get an accurate measurement:

Start with an empty platen, it should indicate zero.
Add your weight quickly, don't slowly pour powder into it for example.
Take the weight.
Remove the item and let it rezero again.

You can weight items in succession without going to zero, but periodically it is wise to let it be empty and zero, say every 5 or 10 items for example.

I greatly prefer digital scales because they give you the value quickly, but you always have to start with an empty platen and zero right before adding a weight and measuring...

Good luck,

Alan

 

[MoBoost]

If I need to weigh something quick - I use digital, for actual reloading I throw in a pan and trickle on beam scale: wondering zero of digital scale was driving me crazy.

 

[Pulp]

At least I know I'm not alone.

Alank, thanks for the explanation.

Kinda rules out trickling up to the desired weight.

 

[NikatKimber]

I pretty much use my digital as a "double check" on charges dropped from either the Auto-Disk or Dillon meter to verify consistency. If I'm trickling up to charge, I'll use my beam scale.

 

[alank2]

Hi,

At least I know I'm not alone.
Alank, thanks for the explanation.
Kinda rules out trickling up to the desired weight.

Sure thing. You can trickle weights when they are off zero and not auto zeroing, but you want to do it quickly. The longer it stays off zero the more time the load cell can fluctuate.

Good luck!!

Alan

 

[Rick Means]

I use an RCBS electric scale and I have found even a breeze from a fan can result in what you are talking about. I remedy this by leaving it in my reloading cabinet on a convenient shelf. I just bought a charge master to hook up to it, and I noticed it has a shield to keep wind off of the scale. Once I learned about the unit's wind problems, and have taken steps to stop it, things have been great. I trust it as much as the beam scale.

 

[Dr_Mitch]

I use the Dillon D-Terminator, and it's been perfect. I use check weights to verify calibration occasionally. The discourse on load beams is good stuff, but more importantly you should take GREAT care of your scale. Weighing things to 1/70,000th (0.1 grains) of a pound is very, very precise and fine instrumentation. My scale does not move, nothing is near it, and I keep it clean and covered at all times that it is not in use. I use it with the AC adapter without batteries installed, and if batteries are installed I unplug the AC adapter.