FX120i drift

[kelbro]

How often do you need to zero these scales?

I finally broke down and invested in an electronic balance with more resolution than the scale on my old Chargemaster.

I have it on a Tripp Lite surge protector/line conditioner.

No fluorescent lights.

No cell phone nearby.

Bluetooth speaker about 5' away.

Ambient temp in the basement is around 60F.

Sorted ~1000 primers (in multiple sessions) and did not see any drift from zero over several days.

Loaded 50 rounds a couple of days ago and did not see any drift.

Latest session:

Loaded a batch of 85 rounds for my 223.

Please take a look at my process and see if there's anything that I'm doing which could cause drift.

1. Zeroed the CM and the FX120i with the Lyman powder funnel pan that I've used for years on the CM.
2. Threw the loads within .2gr on the CM and then moved the pan to the FX120i and trickled up with my Dandy.
3. I did about 20-25 at a time, took a break and returned.
4. Finished in a couple of hours.

Towards the very end of the last batch, I noticed that the readout on the FX120i (without the pan) was not the -xxx.xx value that was set when I tared it early on in the process. It was about .02-.03gr off. But when I set the empty pan on the plate, it read zero.

I checked the last 25 throws and they were all .02-.03gr light.

Never noticed any static charge on the pan or CM.

I am planning to zero more often when I do large batches but I'm not real impressed with this balance if I have to do that. Is there some sort of internal calibration or zeroing going on the the FX120i when it has been tared and the tare weight is removed?

 

[gmr4]

Mine has done the same thing and when I check charges none of them were different so I let it go. This does not happen now that I grounded the scale. The CE products webpage has a few trouble shooting tips www.ceproducts.com one of them is grounding with a copper wire.

I always let it warm an hour or so with no weight on the plate because I unplug all the way when not in use.
I always calibrate with a 100gr weight.

The scale is way better than my Chargemaster Supreme … i hope you see the better SD/ES numbers and smaller groups like I did.

 

[kelbro]

My reloading bench was an ESD workstation in it's previous life but it is not grounded to the earth ground. I can definitely ground the bench and then ground the scale to the bench.

I did find another post on here about the way the FX120i zeros and the suggestion was to NOT zero with the pan on the balance and to just add the pan weight to the desired charge.

 

[Rick300]

NOT zero with the pan on the balance and to just add the pan weight to the desired charge.

That's a great way to make simple things complicated

 

[kelbro]

That's a great way to make simple things complicated

Sounds like it but it had something to do with the way the FX120i auto-zeroes. The post said the scale worked best at absolute zero vs. a tare weight.

 

[ShtrRdy]

If you've grounded the scale and wiped the scale and shield with anti-static sheet then the only other thing I can think of is to make sure the bubble is centered. The level being off center does make a difference

 

[JMayo]

There is s learning curve to everything. Like bench manners in bench rest, there are scale manners that will be learned as you go.
Try things, if they work keep em if they don't let em go
A REAL check weight will aliviate your worrying. After tearing cup weight, no matter what the - shown, check it.

One kernal to much seems like allot one kernal less seems like allot on a scale that has 3 decimals.

 

[Steel Mover]

Reason I have never bought an electronic scale. I have used a balance beam scale for 50+ years. Gravity just works.

 

[kelbro]

There is s learning curve to everything. Like bench manners in bench rest, there are scale manners that will be learned as you go.
Try things, if they work keep em if they don't let em go
A REAL check weight will aliviate your worrying. After tearing cup weight, no matter what the - shown, check it.

One kernal to much seems like allot one kernal less seems like allot on a scale that has 3 decimals.

Yes, I have real check weights from my previous employment and the scale reads correctly when using the check weights.

What I have not done (and did not expect to need to do with a scale at this price) was to continually be checking it while processing.

 

[Kracken McGraw]

Reason I have never bought an electronic scale. I have used a balance beam scale for 50+ years. Gravity just works.

Someone the other day said there balance proved to be off up to two tenths after getting the Fx scale.

 

[rlporter507]

mine does not do that, but i did notice if i leave the pan on the scale when i take a break that was a sure way to have to re-zero. sounds like you have does all the tricks with the conditioner and ground.
?????

 

[Kracken McGraw]

Does .02 mean anything on a target?
Jackie wins all the time in benchrest using the charge master lite and weighing at the range.

 

[gmr4]

My reloading bench was an ESD workstation in it's previous life but it is not grounded to the earth ground. I can definitely ground the bench and then ground the scale to the bench.

I did find another post on here about the way the FX120i zeros and the suggestion was to NOT zero with the pan on the balance and to just add the pan weight to the desired charge.

Its made to zero.

 

[xr650rRider]

Read the thread link below. And temperature changes will cause it to drift. If your room is 60°F and not a large room, your body heat and breathing is warming the environment and you'll start seeing a shift. Scales are meant to tare out the weight of a pan or whatever container your using. If you change platens, cups etc, you should go thru a complete calibration procedure.

https://forum.accurateshooter.com/threads/fx-120i-zero-drift.4062276/

 

[kelbro]

Re-ran the external 100g cal. All of my other check weights read correctly.

I just grounded the scale to the house ground. Set the powder pan on there and will look for drift. After one hour, no drift. That's what I saw before. Very steady for days with a constant weight on the platen.

My basement is about 900sq ft and not heated or cooled except when I fire up the Big Buddy propane heater. I just remembered that I was running the heater that day. That was a variable. Raises the temp at my bench about 6-8 degrees. Who knows. Also, I suppose it's possible that the jacket that I had on that day was generating some static. It has a nylon quilted inner shell. Who knows.

I did run the 3-nickel test from that post and it all checks out just as expected.

I managed a cal lab for a while and our standard procedure in the lab was to tare/zero at each weigh and take multiple measurements. The scales used for production were 'performance checked' every hour but they did not have to get down to the 0.xx grain level for counting.

Maybe my expectations are too high for this scale. I will try a few more best practices before I pass final judgement on it.

 

[64Rambler]

I did find another post on here about the way the FX120i zeros and the suggestion was to NOT zero with the pan on the balance and to just add the pan weight to the desired charge.

I think the suggestion was to turn ON the balance with nothing on the pan and let it go through its start up procedure. It will display 0.000 g. THEN put your weigh dish on the balance and re-zero it. If you start it up with anything on the balance, it will display 0.000 g, but when you take it off, you will get the -E display which in an error code.

 

[xr650rRider]

Using a 1543.236 grain (100 grams) check weight for calibration and then expecting it to weigh to .02 grains is asking a lot of a calibration. I have my scale set to use a 50 gram but that is still way/weigh to high for a good reliable calibration.

 

[hoz53]

Does .02 mean anything on a target?
Jackie wins all the time in benchrest using the charge master lite and weighing at the range.

probably not at 100 but at 1000 or so probably yes.

 

[kelbro]

I think the suggestion was to turn ON the balance with nothing on the pan and let it go through its start up procedure. It will display 0.000 g. THEN put your weigh dish on the balance and re-zero it. If you start it up with anything on the balance, it will display 0.000 g, but when you take it off, you will get the -E display which in an error code.

Thanks. That was another post. The one that I was referring to was not about the error message.

 

[kelbro]

Using a 1543.236 grain (100 grams) check weight for calibration and then expecting it to weigh to .02 grains is asking a lot of a calibration. I have my scale set to use a 50 gram but that is still way/weigh to high for a good reliable calibration.

I agree that it would be best if the calibration was closer to the subject weights but that's out of our control. I do run the performance checks with my check weight standards in the range of the powder that I'm using as a 'feel good'