When to recalibrate FX120i

[JimSC]

I calibrate mine before each session, it quick easy, painless, and cost free so why not

 

[308 5R]

Humidity level (static Mitigation), temp stability, and clean power source/solid grounding of the unit are the keys that I have found. Mine stays on unless I leave for an extended period of time or if there is an expected thunderstorm. Before every use the unit is checked for drift with a certified check weight and calibrated regardless of the outcome. I have never witnessed any drift from calibration more than +/- .002-3 mg, but as was stated earlier in the thread, calibration only costs 20-30 seconds of your time.

ETA: One of the cheap import 9x12 or so “granite“ plates leveled with something like a Starrett 98 are nice item to place the unit on to help with movement around it.

S/F
Ryan

 

[coford]

I have two of the FX120i scales and I have learned a lot using them. First - get your cell phone away from them - it will cause drift. Second shut off the TV - it will cause drift. Third - get rid of your fluorescent lights - they will cause drift and LED's won't. Fourth make sure you don't have any cobwebs or dust bunnies under the scale - they will cause drift. Fifth buy a line conditioner as it will help. Lastly tell the wife to shut off the dishwasher that sits upstairs, directly above your reloading bench - it will cause drift. The mentioned items will cure 99% or the drift issues or at least did for me. These scales are very accurate but are also very sensitive.

 

[gman47564]

mine is plugged into a surge protector... i shut the scale off after each session... when i turn it on and sit the pan on it if it doesnt have the right number on it i recalibrate it... if it does have the right number i carry on... sometimes even after recalibrating it the weight of the pan is off .02... when it does that if i wipe the pan out good it goes back to the number im looking for... i guess the pan can get enough powder residue on it to throw it off .02... cant see it on there but it makes a difference wiping the pan out...

 

[Gil P.]

mine is plugged into a surge protector... i shut the scale off after each session... when i turn it on and sit the pan on it if it doesnt have the right number on it i recalibrate it... if it does have the right number i carry on... sometimes even after recalibrating it the weight of the pan is off .02... when it does that if i wipe the pan out good it goes back to the number im looking for... i guess the pan can get enough powder residue on it to throw it off .02... cant see it on there but it makes a difference wiping the pan out...

I'll try that. What do you wipe the pan with to mitigate static?

 

[gman47564]

its not from static i dont think gil p... my pan just gets a powder residue built up on it i think.... i can wipe the pan down with a clean rag and its good to go again... i have also heard its good to unplug them every now and then to erase the memory in it.. which i do now and then...

 

[Gil P.]

I have two of the FX120i scales and I have learned a lot using them. First - get your cell phone away from them - it will cause drift. Second shut off the TV - it will cause drift. Third - get rid of your fluorescent lights - they will cause drift and LED's won't. Fourth make sure you don't have any cobwebs or dust bunnies under the scale - they will cause drift. Fifth buy a line conditioner as it will help. Lastly tell the wife to shut off the dishwasher that sits upstairs, directly above your reloading bench - it will cause drift. The mentioned items will cure 99% or the drift issues or at least did for me. These scales are very accurate but are also very sensitive.

My garage has a bunch of fluorescent lights and I use the app on my cell phone to set the charge weight on the FX120i. I rarely get drift. Might this sensitivity vary from scale to scale?

 

[J-rod]

I have never calibrated my scale..so you guys have me worried.
I usually drop a 10g and then 20g weight on the scale before use and they always ready 10.000 or 9.999 and 20.000 respectively so I figured that was good enough? Mine is on a conditioner and surger protector, and only LEDs around it.

 

[1TXshooter]

Clean power source is the answer. Just my two cents. Tommy Mc

I agree 100% with this. Using a clean power source solved all of my FX120i scale wandering problems.

I use a double conversion UPS, which generates clean AC power via an inverter powered by batteries. The typical line-interactive UPS only makes AC power from its batteries during a power failure and don't really do any meaningful power conditioning. I have also tried running my scale off a battery pack, but the double conversion UPS seems to work better.

 

[Dub]

I have two of the FX120i scales and I have learned a lot using them. First - get your cell phone away from them - it will cause drift. Second shut off the TV - it will cause drift. Third - get rid of your fluorescent lights - they will cause drift and LED's won't. Fourth make sure you don't have any cobwebs or dust bunnies under the scale - they will cause drift. Fifth buy a line conditioner as it will help. Lastly tell the wife to shut off the dishwasher that sits upstairs, directly above your reloading bench - it will cause drift. The mentioned items will cure 99% or the drift issues or at least did for me. These scales are very accurate but are also very sensitive.

pretty much like any electronic scale.....

 

[Evan]

I don't calibrate my FX120 hardly ever. I hit the on button, let it sit for 10 or so minutes while I prep other things and right before I start, I place my 50g calibration weight on the scale. I think I can recall one time that it read 49.99 instead of 50.00, requiring a re-calibration. When your pan weighs something different, have you tried your 50g cal weight to see if it still weighs correctly? Do you have an indicator or mark on the platten so that you always place your pan in the same spot?

 

[Gil P.]

I don't calibrate my FX120 hardly ever. I hit the on button, let it sit for 10 or so minutes while I prep other things and right before I start, I place my 50g calibration weight on the scale. I think I can recall one time that it read 49.99 instead of 50.00, requiring a re-calibration. When your pan weighs something different, have you tried your 50g cal weight to see if it still weighs correctly? Do you have an indicator or mark on the platten so that you always place your pan in the same spot?

The 100g calibrated weight will usually weigh 100g after calibration, sometimes it weighs 99.999g.

Yes I have the plastic crescent shaped thing glued to the weighing platform so the pan always sits on the same spot.

 

[Ned Ludd]

When you tare [zero] a balance that already has some given weight on the pan (such as a powder dish) and then remove the weight, a negative weight value may be displayed. However, that negative value may not be either accurate or reproducible. Balances are not designed to provide accurate or reproducible weight values that are less than zero. This is not unusual in that many laboratory instruments are not designed to provide accurate/reproducible negative values. As long as the balance gives you a reproducible weight for the powder dish every time when the balance has first been tared [zeroed] with the balance pan empty, then it is working correctly. You can then assess its accuracy via the use of calibration weights, or by weighing the same item on another balance which you are confident is accurate.

FWIW - there is nothing wrong with calibrating the balance every time you use it. In fact, that is considered standard practice, and I would recommend to anyone to obtain a decent set of calibration weights that includes at least one weight close to the value of the samples you most often weigh on the balance. For example, we typically weigh powder charges that fall in the 20 to 60 grain range or thereabouts (~1 to 5 grams), depending on the cartridge. Thus, an appropriate calibration set might include weights of 1 g, 2 g, and 5 g. Calibrating a powder balance with only a 100 g or a 0.01 g weight in such a case would not be ideal, although it would certainly be better than not calibrating it at all.

 

[dgeesaman]

Thus, an appropriate calibration set might include weights of 1 g, 2 g, and 5 g. Calibrating a powder balance with only a 100 g or a 0.01 g weight in such a case would not be ideal, although it would certainly be better than not calibrating it at all.

I have a single 2 gram test weight. At 30.865grains, it’s about the weight of a PPC or BRA charge.

What matters to me is my scale getting from its current zero to that 30.865 value. I just need to pause my trickler and add the test weight if I have any doubts.

The full recalibration process has never been necessary. Just the occasional rezero and management of external effects.

David

 

[JMayo]

Oils from hands, dust in the air, residue from powder get on pan.
I can wipe my pan down really good and change its weight. .258 - .262 clean.
.270 is dirty.
Touching the weight used to calibrate caused the same problem. I use a paper towel like a choke vice to place weight. Also wipe off scale plate.
I have a certified check weight for my lab scale.

I Calibrate after moving it from store place to work space & leveling.

I ruined a brass check weight by using a scouring pad to clean it ... Used tape pieces to get it to weight again