Why is my RCBS scale tipping in the presence of this plastic? Head scratcher!

[GJgo]

This is a weird one, need some help 'splainin. I use a RCBS 5-0-5 scale. The zero tends to float 0.1 grain from day to day, so I always re-zero, no big deal.

Recently I picked up one of those media tumblers from Cabela's that seperates the brass from the cleaning media. I had run a load through, and sat the plastic tumbler thing on my loading bench (full of clean brass) next to the scale. What the heck, the scale just tipped?!?! Pull it away, scale zeroes. Put it back, scale tips. This is weird. I'm not touching the scale, and I'm not touching the bench. It's like the magnetic field is being disturbed, but it's not a magnetic scale- and the tub is plastic!

What the heck is going on? Subsequently I tried getting just the brass close & it didn't affect it. I tried just the plastic bucket & there it is. I tried some other plastic things I had around and nothing. I'm stupefied.

 

[Fishslayer]

Static attraction.

Try rubbing the plastic with a drier sheet & see what happens.

 

[GJgo]

That certainly seems plausible, however I didn't "feel" any static on / near the plastic. Doesn't mean it wasn't there I suppose.

 

[chhodge69]

Your flux capacitor is creating an inverted warp field and knocking the power coupling out of phase.

 

[788Ham]

STATIC ! Rub a blown up balloon on your head, then put it next to a cat, notice how the hair stands up? STATIC my man! Science 101.

 

[GJgo]

I think I'm gonna go with the flux capacitor suggestion.

 

[Certaindeaf]

Burn some sage. Not me though.

 

[blarby]

Magnetic dampener.

Static electrical field.

There ya go

 

[twofifty]

Whatever you do, DO NOT p on that plastic tub !

 

[redneck2]

STATIC ! Rub a blown up balloon on your head, then put it next to a cat, notice how the hair stands up

Yeah, but then do you put your head, the cat, or the balloon next to the scale??

 

[GJgo]

No way is my cat getting near my bench!

 

[steve4102]

Magnetic dampener.

 

[FROGO207]

I have been trying to teach my cat how to reload for years. All he will do so far is push the buckets of brass off the shelf and bat the individual casings around on the floor. This usually happens between 1AM and 4 AM.:banghead:

Yeah all that media running around in the tub is creating a static charge that is attracting the scale beam. If your scale is drifting any try cleaning the knife blades and the ceramic holder with a Q-tip dipped in rubbing alcohol. This usually will stop most problems.

 

[JohnM]

It's a charge being built up in that plastic separator. Plastics are among the most complex compounds around.
Whichever ones used in yours evidently is good for holding a charge.
Just keep it off the bench and away from your scale.
Helps to have a pack of those anti static computer wipes around for wiping down some of the plastic items we always end up having on our reloading benches.
Don't talk to me about CATS!
I got one that always wants to come into the reloading room to see what I'm doing.

 

[The Bushmaster]

Steve4102 has it. The 5-0-5 is magnetically dampened and the static buildup in the plastic seperater is the cause.

The change you are seeing in the first thing you noticed in that the scale changes from day to day is +/- .1 is caused by atmospheric pressure.

OR you might check for space alians outside your window.

 

[The Grand Baboon]

Your flux capacitor is creating an inverted warp field and knocking the power coupling out of phase.

^^^^

 

[Certaindeaf]

It might just be a static buildup. Never know, man!

 

[CHALK22]

Get your reloading room wired for 220v 3-phase, and then install a voltage inverter, drop it down to 12 volt, and install one of those auto air purifiers. That oughta do it.

 

[Lost Sheep]

The change you are seeing in the first thing you noticed in that the scale changes from day to day is +/- .1 is caused by atmospheric pressure.

Can anyone explain how this works?

I can understand static attraction. I can understand magnetic influence. I can understand air movement. I can even understand capacitance. But air pressure?

Anyone?

Lost Sheep

 

[rcmodel]

Air pressure or air density would not change a scale zero because it would be applying pressure equally all over the scale.

Air temperature could change it 0.1+/- due to expansion or contraction of the scale beam.

rc

 

[kennedy]

wipe the plastic with a dryer sheet

 

[FROGO207]

With a oil dampened scale I could see your actual dampening time changing due to the oil density changing with the atmospheric pressure----IF you could measure that small a difference with your scale. I would be more inclined to think that the moisture in the air (humidity) was allowing the wood of the floor joists, floor, and/or table to expand and contract at different rates and causing the table to tip slightly while gravity acting on the balance arm was remaining the same hence your small movement.

 

[788Ham]

redneck2,

YES!

 

[exbrit49]

Static static static

The Plastic container is carrying a static charge and hence creating a magnetic field that is screwing up the magentic damping on the scale.
As suggested you can use a dryer sheet to try to help dissipate the Static and EMI fields.
Increasing the humidity might help but I doubt it will help that much. Get the plastic container well away from the scales. the field EMI field can extend several feet.
Static is generated by friction , you have seen people rub balloons and have then stick to everything, think of the media in a tumbler constanlty moving against the container surface, I bet its getting up there close to 20KV!
I bet if you ran a static Voltage meter on that Tumbler container its probably carrying well over 20 to 30 KV.
Roger

 

[ScottRiqui]

Static electrical fields don't generate magnetic fields.

You may still be seeing an attraction from the static field alone, just like a plastic or glass rod with a static charge on it will attract small scraps of paper.