RCBS 505 scale keeps losing zero
- Thread starter 45C
- Start date
Have you checked the gap where the copper plate runs through?
Metal filings could stick to the sides due to the magnets and interfere with free movement of the copper plate.
I have had many ohaus made rcbs, Lyman and ohaus scales over the years and still have two rcbs and two Lyman ones and never seen the condition you described on a cleaned scale with undamaged knife edges and bearing blocks.
Metal filings could stick to the sides due to the magnets and interfere with free movement of the copper plate.
I have had many ohaus made rcbs, Lyman and ohaus scales over the years and still have two rcbs and two Lyman ones and never seen the condition you described on a cleaned scale with undamaged knife edges and bearing blocks.
I had issues with it a couple of years back and added the teflon tape as was mentioned earlier. That helped but never quite as good as before.
Is it possible that the +/- adjustment wheel screw is wearing too much ? Without the teflon tape it has a bit of play.
It gets a lot of use.
I’m going to give it a thorough cleaning anyway.
I should get something else as a back up anyways.
Falconflyer
CGN Ultra frequent flyer
I’ve had an RCBS 5-10 for several decades now and it’s highly dependable if you keep the pockets where the knife edges rock back and forth clean. It only takes a bit of dust that can’t even be seen to make the balance beam unreliable and a quick shot of air fixes the problem, in fact just blowing on them does the trick most of the time. I wouldn't trade that scale for any other and I’ve tried several electronic scales.
The only scale Ive ever used, and it's still doing just fine since 1977.
Mystic Precision
CGN Ultra frequent flyer
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Bite the bullet... FX120i.. live happily ever after
Jerry
Jerry
A couple things you can try.. remove the magnets from their recesses in the scale body and wipe them down so nothing magnetic (ferrous) is clinging to them. Also make sure the agate blocks the knife edges ride on are clean.
Finally, check the knife edges. They should be clean, smooth and aligned with each other. If the beam got dropped at one time, they could have gotten bent. If one is bent it'll do what you're describing.
I had a similar problem with my 5-0-5 several years ago, removing and cleaning the magnets fixed it.
I don't fully understand why, since they weren't covered in metal filings or really anything that I could see, but it's worked fine ever since.
A friend told me his was acting up one time, and passing a piece of steel back and forth between the magnets a few times fixed it.
The older 5-0-5's were one of the best scales Ohaus ever built, just rebranded for RCBS. I wouldn't part with mine for love or money. It's sensitive enough to register a single kernel of N140 sized powder.
I have enough headaches in my life without adding more electronic shi* to the list of stuff that can go wrong and I can't fix when it does. You'll notice I didn't say "if" it goes wrong.
As has been said, if you're going to go digital, don't go cheap.
Finally, check the knife edges. They should be clean, smooth and aligned with each other. If the beam got dropped at one time, they could have gotten bent. If one is bent it'll do what you're describing.
I had a similar problem with my 5-0-5 several years ago, removing and cleaning the magnets fixed it.
I don't fully understand why, since they weren't covered in metal filings or really anything that I could see, but it's worked fine ever since.
A friend told me his was acting up one time, and passing a piece of steel back and forth between the magnets a few times fixed it.
The older 5-0-5's were one of the best scales Ohaus ever built, just rebranded for RCBS. I wouldn't part with mine for love or money. It's sensitive enough to register a single kernel of N140 sized powder.
I have enough headaches in my life without adding more electronic shi* to the list of stuff that can go wrong and I can't fix when it does. You'll notice I didn't say "if" it goes wrong.
As has been said, if you're going to go digital, don't go cheap.
Clean it. Verify it with check weights afterward.
I've heard of the magnets acting up if you're in or near an electrical field (though this sounds like BS to me).
Plus, make sure there are NO fans turning in the room, NO furnace or AC running, don't sit in a sunny spot where a dark-coloured desk top radiates heat upward.
Any moving air at all will cause what you're experiencing.
I've heard of the magnets acting up if you're in or near an electrical field (though this sounds like BS to me).
Plus, make sure there are NO fans turning in the room, NO furnace or AC running, don't sit in a sunny spot where a dark-coloured desk top radiates heat upward.
Any moving air at all will cause what you're experiencing.
I zeroed the scale and tested it 6 times and it was consistent but when I checked the zero again it was out this much ( in the picture)about 3 or 4 kernels.View attachment 754735
It takes about a minute or three for the balance beam to stop moving as it’s overly sensitive now.
When I removed the bottom of the bowl holder? There were 5 small black balls and several , what appears to be aluminum shaving pieces in there.
I didn’t put the aluminum shavings back in .
It takes about a minute or three for the balance beam to stop moving as it’s overly sensitive now.
When I removed the bottom of the bowl holder? There were 5 small black balls and several , what appears to be aluminum shaving pieces in there.
I didn’t put the aluminum shavings back in .
When I use my beam scale - I have a wooden cutting board with a set screw in each corner (to adjust the height) with four round bubble levels at each corner - I have the board completely level before I put the scale on it - I would measure every 5 or so weights with a GENpro 250 and it's accurate within .01
Because I am farsighted I use a magnifying glass to see when the beam reaches zero
Because I am farsighted I use a magnifying glass to see when the beam reaches zero
Sounds like you are missing or have dislocated dampening magnet/magnets, have a look from underneath to see if you have a magnet on either side of the copper plate in the frame. Or remove the beam and take a paperclip and check if it sticks to either side. (check one side at a time)
If you don't understand what I'm talking about and need a picture/pictures then let me know and I'll grab my scale and take a pic.
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