Digital scale anti-vibration

[MikeRu]

This is going to sound snarky, but it's actually the right anwser. Don't put your elbow on the bench while the scale is doing its thing.

This is the answer

 

[6Creed73]

This is the answer

If I was lazy, that would maybe be enough. But I'm not, so the answer is to ensure a very sensitive analytical balance has the proper base to make sure it can work optimally. Which is probably why using a solid base is the first bullet from the manufacturer on how to setup the scale and why the scientific community routinely uses heavy marble and granite slabs to stabslize sensitive balances.

As I've already stated, lightly resting my elbow on the bench was simply an example of the balance not being stable. If barely resting my elbow on the bench causes it to register then that means any number of things can interfere with it. Which means the right answer is to make sure it has a stable base.

 

[Fast14riot]

When measuring with such finely tuned equipment, training and environmental treatment is required to ensure accuracy and precision. You cannot expect a sensitive scale like that to be as stable and insensitive as a lesser unit. When measuring small special skills are required.

I turn off all fans on the entire floor of the house I'm loading in, close all doors, scale is left on for at least one hour before weighing, I use a breath shield, no lighting is altered before or during a weighing session. If someone opens the door to come downstairs, I can see it.

Put another post under your bench in the middle. Get a granite surface plate. We all have masks laying around one can wear to keep your breath at bay, in addition to the enclosure.

Special equipment requires special skills.

 

[6Creed73]

When measuring with such finely tuned equipment, training and environmental treatment is required to ensure accuracy and precision. You cannot expect a sensitive scale like that to be as stable and insensitive as a lesser unit. When measuring small special skills are required.

I turn off all fans on the entire floor of the house I'm loading in, close all doors, scale is left on for at least one hour before weighing, I use a breath shield, no lighting is altered before or during a weighing session. If someone opens the door to come downstairs, I can see it.

Put another post under your bench in the middle. Get a granite surface plate. We all have masks laying around one can wear to keep your breath at bay, in addition to the enclosure.

Special equipment requires special skills.

I agree, I do the same thing. I turn off the dehumidifier, turn of the AC, turn off the fluorescent overhead light, etc. This scale comes with a draft shield, so I don't have to worry about breathing on it. I also plug mine into a line conditioner so it's getting clean power.

Stability on the bench wasn't an issue with my last scale, but this one is much more sensitive. Which is why I was asking for leads on a base, because they can be expensive. Thanks to @Sigma I ordered the one he suggested from Grizzly.

If the granite base doesn't improve it enough, I'll probably beef up the bench supports like you mentioned, or do the tennis ball and sand idea mentioned by another member.

 

[jimmymac]

I just got a left over piece of thick countertop stone from a local place and built a bench to those dimensions. The stone weighs 120 pounds or more. I’m having zero issues with a FX 120i even when seating bullets on the same bench. No bobbles.

 

[Punkur67]

I got a thick peice of granite off Amazon and put rubber feet on it. I also took a scrap of the countertops and glued and screwed to the bottom the whole width between the cabinets. I can seat bullets while powder is trickling without any issues

TTC 12" x 18" x 3" Thick Grade B No Ledge Black Granite Surface Plate https://a.co/d/9hW4rgN

 

[MikeRu]

If I was lazy, that would maybe be enough. But I'm not, so the answer is to ensure a very sensitive analytical balance has the proper base to make sure it can work optimally. Which is probably why using a solid base is the first bullet from the manufacturer on how to setup the scale and why the scientific community routinely uses heavy marble and granite slabs to stabslize sensitive balances.

As I've already stated, lightly resting my elbow on the bench was simply an example of the balance not being stable. If barely resting my elbow on the bench causes it to register then that means any number of things can interfere with it. Which means the right answer is to make sure it has a stable base.

Just trying to be helpful. I have a very heavy bench over a concrete floor, but if I rest my arms on the bench and then pick them up, the balance detects that every time. So for me it’s “hands up” while the balance settles on a reading. Otherwise any body movement, air drafts or vibrations are detrimental as you know.

 

[6Creed73]

Just trying to be helpful. I have a very heavy bench over a concrete floor, but if I rest my arms on the bench and then pick them up, the balance detects that every time. So for me it’s “hands up” while the balance settles on a reading. Otherwise any body movement, air drafts or vibrations are detrimental as you know.

Yeah, I try to keep my hands off the bench as well while the trickler is running. But this new scale even registers sometimes when the vibratory trickler is going. To confirm, I set the trickler next to the scale but was just dropping powder into a cup off the scale and the scale would register similar to when I touch my elbow to the bench.

So I just want to give the scale the most stable base I can. I have a 3" thick 50lb slab of granite on the way...surely that will help.

 

[Tesoro]

Tuned ohaus M5 helps solve this problem

 

[6Creed73]

Tuned ohaus M5 helps solve this problem

Ha! Although I do like a good beam scale, I'd never go back to using one exclusively. It's just too slow, and these analytical scales are extremely accurate. I do use a beam scale as a sanity check though.

 

[dcali]

This is more intended for newer shooters than the OP, but It's probably worth saying that you've gone way past overkill - to fishing with nukes. Most guys using fancy digitals are using an FX-120i. I have one on a bench that doesn't so much as flicker while I'm pulling bullet cores on the same bench. They're not as precise as yours, but they're more precise than we need them to be. You're kind of doing it the hard way.

 

[6Creed73]

This is more intended for newer shooters than the OP, but It's probably worth saying that you've gone way past overkill - to fishing with nukes. Most guys using fancy digitals are using an FX-120i. I have one on a bench that doesn't so much as flicker while I'm pulling bullet cores on the same bench. They're not as precise as yours, but they're more precise than we need them to be. You're kind of doing it the hard way.

You aren't wrong. Does anyone need a scale for reloading that is accurate to 0.001gr? Nope, and I'd say the same thing to someone asking advice about what scale to get. The FX-120i is a great scale and it is overkill as well...but it doesn't stop us from chasing perfection anyway. I'm a systems engineer so I can't help it lol.

But the real reason I upgraded is I wanted a magnetic force balance to combat zero drift...which this new one does very well, as does the FX-120i.

BTW, while I'm waiting for my granite slab to get here, I temporarily put it on a 12"x12" concrete patio paver to load up some rounds yesterday, and it worked perfectly. I could lean on the bench without issue, so the granite will take care of it.

 

[Rocketvapor]

Your patio paver added mass to the balance/scale platform.
Just like a barrel tuner changes the frequency and magnitude of vibrations.
Force balance scales will respond to vibration, sway, and tilt because of the hanging method used to support the pan. Movement (load) in the vertical axis is sensed and opposed with an electromagnet.
One advantage of a surface plate is the smoothness/flatness of the plate. Once leveled, any spot will be about the same as another. If your scale's feet don't turn when moved, movement about the plate should not affect level. A convenience over a rough surface or one that the feet can dent, like wood.

 

[SKWERLZ]

This is more intended for newer shooters than the OP, but It's probably worth saying that you've gone way past overkill - to fishing with nukes. Most guys using fancy digitals are using an FX-120i. I have one on a bench that doesn't so much as flicker while I'm pulling bullet cores on the same bench. They're not as precise as yours, but they're more precise than we need them to be. You're kind of doing it the hard way.

Having a scale able to resolve a single grain of the powders I try to be precise with and it being fast is a nice combination.
My ES didn’t get substantial better than my old powder setup but it’s substantially faster with no loss of accuracy whatsoever.

 

[Rocketvapor]

From Wiki:
Early seismometers used optical levers or mechanical linkages to amplify the small motions involved, recording on soot-covered paper or photographic paper. Modern instruments use electronics. In some systems, the mass is held nearly motionless relative to the frame by an electronic negative feedback loop. The motion of the mass relative to the frame is measured, and the feedback loop applies a magnetic or electrostatic force to keep the mass nearly motionless. The voltage needed to produce this force is the output of the seismometer, which is recorded digitally.
In other systems the weight is allowed to move, and its motion produces an electrical charge in a coil attached to the mass which voltage moves through the magnetic field of a magnet attached to the frame. This design is often used in a geophone, which is used in exploration for oil and gas.

A force balance scale is basically a seismograph in reverse. Some vibration frequencies can be electronically filtered out, while some frequencies can produce reading errors. Adding mass, like a surface plate under an instrument changes the response to frequency and magnitude of external forces. The durability and strength of the pan supports of a Force Balance scale need to be stronger (less sensitive) for a scale designed for a 'shop' than a 'lab' environment. Damage can cause loss of sensitivity (to small changes in load) that can also show up as linearity error. Deviations from level can produce errors in any device that uses gravity as the force initialing movement. A scale tries to measure the vertical component of local gravity. Local gravity is pretty darn stable, no matter what the media says.

The precision and stability of the metering circuitry in a scale (measuring voltage or current) determines most of the specified performance parameters. Most digital measuring devices need an internal highly stable voltage reference and a high resolution analog to digital converter. Modern electronic measuring instruments are capable of high precision at very reasonable cost. Conditioning of the input electricity is needed if internal circuitry is inadequate. Shielding from external electromagnetic fields can affect electronic devices, even force balance scales.

A Google search on voltage references should give some info.

How to Use a Voltage Reference to Ensure Accurate, Stable Data Conversion

Proper use of a carefully selected voltage reference ensures analog-to-digital and digital-to-analog conversion accuracy and optimum system performance.

www.digikey.com

For the next class we will discuss A to D convertors

 

[Tesoro]

Is there a special tool one uses to cut the kernels to get to the 1/1000 gr accuracy? or does one just use a razor blade and jewelers loupe?

 

[6Creed73]

Is there a special tool one uses to cut the kernels to get to the 1/1000 gr accuracy? or does one just use a razor blade and jewelers loupe?

It's not a thousandths of a kernal, it's a thousandths of a grain, the measurement of weight. I've never met anyone who actually cuts the kernals. Even +/- one whole kernal is unlikely to make a difference in ES/SD and I certainly can't shoot the difference.

If my targeted charge weight is 40.5 grains, my scale can read to 40.500...I usually just get it as close as possible to the middle, so 40.550. If the charge ends up weighing out to 40.570 it will make no real difference in that load.

 

[Rocketvapor]

Maybe sort out some light and heavy kernals. Use to fine tune your load. I get a range from 100 to 150 counts with Varget. Save for later in little 1 Dram bottles.

 

[6Creed73]

Maybe sort out some light and heavy kernals. Use to fine tune your load. I get a range from 100 to 150 counts with Varget. Save for later in little 1 Dram bottles.

View attachment 1463128

Yup, I've swapped out a large kernal for a small one before with tweezers to get closer to my target weight...Now I'm exposing my OCD to everyone

 

[Tesoro]

It's not a thousandths of a kernal, it's a thousandths of a grain, the measurement of weight. I've never met anyone who actually cuts the kernals. Even +/- one whole kernal is unlikely to make a difference in ES/SD and I certainly can't shoot the difference.

If my targeted charge weight is 40.5 grains, my scale can read to 40.500...I usually just get it as close as possible to the middle, so 40.550. If the charge ends up weighing out to 40.570 it will make no real difference in that load.

I know! That was a joke. A 10th of a grain threshold is sufficient.