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454gene
04-25-2015, 11:30 AM
Had a problem with my electronic scale but it turns out it was the plastic powder dump pan affecting the zero. After taking apart the powder measure of my Dillon 550 to check for problems I started to weigh loads, when the plastic dump pan was about a 1/4 inch away from the scale the digital readout would change. I rubbed the outside of the dump pan with a dryer sheet and tried again and this time no change in the readout.
Did a little static electricity cause this?

EDG
04-25-2015, 11:36 AM
Yes. I have seen this with my scale. My scale came with a pan cover that grounds when placed on the scale. Apparently it is a Faraday cage to keep static from affecting the scale.

Is your scale a Dillon DeTerminator?

454gene
04-25-2015, 11:52 AM
It's a myweigh i201. The unit has a large plastic box with a sliding door that covers the pan.
How would I ground it? Would a steel pan prevent this problem?

EDG
04-25-2015, 02:48 PM
You might wipe the box inside and out or rinse it in a Dawn liquid soap solution and let it dry.
The characteristic of a Faraday cage is it is conductive. So make sure your box at least a little conductive.
Static charges are "like" charges so they repel each other. The inside of the box requires the charges to be closer and they will always repel to the outside of the box. If your box is conductive the static charge will go to the out side where it cannot easily affect the scale.
If you make your box conductive you could run a ground wire to it and to an earth ground which will drain off any static charge.
If you are standing on carpet with rubber or leather shoes you may be generating the charge yourself. If so use a grounded anti static mat on the floor and if you continue having it use a conductive surface or mat on the table under the scale and ground it too.

You can probably find better information on the net for preventing and controlling ESD.

http://bulletin.accurateshooter.com/2015/03/tech-tip-reduce-electronic-scales-drift-with-anti-static-spray/

Also check the bottom of page 1 of the Myweigh instructions http://myweigh.com/resources/manuals/ibalance201.pdf

In the early 1940s my grandfather drove his car up to a pasture gate outside the farm house.
When he stopped, lightening struck the car. My mother and my uncle witnessed this from the porch of the house.
After the lightening strike my grandfather got out of the car, opened the gate and drove through. The lightening strike did not kill the car engine or enter the car with my grandfather in any way. This is all explained by the inability of a static charge to remain on the inner surfaces of a hollow conductor. To get inside a hollow conductor the charge has to get closer but the same polarity charge can only repel itself to the outside.

http://en.wikipedia.org/wiki/Faraday_cage

bangerjim
04-25-2015, 05:42 PM
Yes static electricity is your enemy.

That is why I only use metal pans and anti-stat funnels and powder handling stuff. I tried to go cheeeeeeep with funnels from the dollar store.......bad choice! Weight readings all over the map.

Acquire the proper metal stuff and you will be fine.

Get one those RCBS gold aluminum pans. Great performance.

banger

454gene
04-25-2015, 06:07 PM
could the static be coming from the powder? I pour Bulls eye from a 4lb. plastic jug.

bangerjim
04-25-2015, 09:13 PM
I do not have any BE, but most of the powders I use have grapite in them to help cut static.

TrailBoss and ETR7 (which I use a lot of) do not have it and tend to stick like "foam peanutz" to plastic. That is why I use metal and anti-stat tools

Standard BLACK powder jugs are made to block UV and try to minimize static. But depending on your RH, you will get static.

Cowboy_Dan
04-26-2015, 11:14 AM
I have the Hornaday GS 1500 electric scale. Noticed that the zero on it likes to wander a bit, so I got an old Herters beam balance to do powder with and use the electric in instances where extreme precision is not necessary

w5pv
04-26-2015, 11:56 AM
Go so disgusted with my electronic scale that I gave it to a fried.To me one that I could afford was not trust worthy.The last time I was over his he was using a beam scale.

Mike W1
04-26-2015, 11:18 PM
Did a lot of testing with my Pact BBK years ago and when it comes to tenth's of a grain it isn't that accurate. In fact I believe the manual says 2/10's of a grain which is more in line with my findings. In order to give it as much help as I could I cobbled this thing together so it's absolutely level and the aluminum plate is grounded and there's about a dozen ingots of lead in there so it doesn't move around.

http://i171.photobucket.com/albums/u310/Mike4245/HPIM1079.jpg

osteodoc08
04-27-2015, 11:51 AM
Nice looking base there Mike! What a nifty idea. Hope you don't mind me stealing it when I build one myself.

Mike W1
04-28-2015, 09:28 PM
Nice looking base there Mike! What a nifty idea. Hope you don't mind me stealing it when I build one myself.

Long as someone thinks it's a good idea here's the one for my beam scale. Same principle, and the trickler base itself is poured with lead as is it's base. Magnifying glass aids viewing immensely.
http://i171.photobucket.com/albums/u310/Mike4245/Scale-Trickler_zpshzovu7vr.jpg