RCBS 5-10 scale Question???

I have a used RCBS 5-10 scale that I am having problems with, can't seem to get the beam assy, to center on the 0 (zero), when centered and I tap the beam assembly down it come to a stop at one line below the zero, and when I tap it up is comes to a stop at one mark above the zero. Contacted RCBS and they say that normally it is the agate bearings are worn so they are sending me a set which should be here today. What I would like to know is the Dial Plate has a 0 (zero), then 5 lines above the zero and 5 lines below the zero and then 3 dots below the lower 5 lines, what do these lines indicate, are they grains or just lines to center the beam assembly? I come here because someone on this site can answer this query of mine. This is just for my information. Thanks to all who know what these lines are and are not just guessing but actually know the the lines represent.

 

It appears they're just simple reference lines to let you know how close you are to zero. They don't appear to be calibrated to represent any specific weight.

Newer 5-10 scales have a different dial plate with an "arrowhead" that RCBS describes as being used as an "approach-to-weight" feature. (See - https://www.rcbs.com/on/demandware....dfFiles/rcbsPdf/Model510ScaleInstructions.pdf )

I suspect the reference lines and dots on your older scale are an older version of the "approach-to-weight" feature that has since been updated by the newer design.

I viewed this YouTube video and based my opinion on the tests he conducted -

 

I got two Agate Bearings today from RCBS @ No charge and that is exactly what the problem was. I centered the beam and tapped the beam down and it returned to zero, I made the beam go up and it also returned to zero which I guess fixed the problem. This is what RCBS said the problem was, not the knives unless they were damaged, Nicks and such. THEY WERE RIGHT!! I want to thank all who responded

 

Does anyone know where to get new RCBS scale knife edges? I would like some, just in case mine ever wear out!!

I was watching a video on how to take care of you RCBS 5-10 scale and the guy doing the video uses a touch of graphite in the bearings, does that sound right to you?

 

I seem to recall the most common advice on beam scale bearings is to make sure they are clean and do not put any sort of lubricant on them.

 

Our member 1066 is the balance beam expert on this forum. Searching his posts might help or you could PM him with a specific question. I seem to remember that the knife edge part is not available as a seperate unit and the whole balance bar is replaced. It was made by Ohaus scales. Also this part was discontinued and they just replaced the whole scale (with a Chinese one sadly).

 

Several guys do that however I prefer to clean the sharp edges with alcohol on a Q tip

 

For anyone who may experience a similar beam reaction, be sure there is ZERO air movement across the beam. The slightest air movement affects the accuracy.

 

If you are looking for any parts on an RCBS scale contact them and buy what you need.
But...
IMO you will not need to replace the blade but if you do, the warranty cover that.

I own an Ohaus 10-10 and an Ohaus/RCBS 5-0-5 and neither need the blade replaced and the 10-10 is probably over 30 years old and the 5-0-5 25 years of so.

I did have a 5-0-5 that was in terrible shape when I bought it used with a bad blade and seat. (abused, not overused) and sent it to RCBS for repairs. I expected to pay for the work but they told me no charge and they even paid return shipping.

 

How many years ago was that ?

 

Check the powder pan hanger. The aluminum wire that the hook of the pan support hooks in. Make sure it’s not bent and binding and all the load is on only one side of the beam.

 

I'm not 100% sure but I think it was about 7-8 years ago.

 

RCBS sent me new agate bearings and I replaced them. The center line will just either center or the lines are either at the top edge of the pointer to the bottom edge of the stationary center line or the visa versa. really close. I weighed some powder today on my RCBS 505 scale and dumped the measured amount into the pan on the 5-10 scale and it centered and measured exactly the same so I guess close is OK. It wouldn't even matter being maybe 1/2 grain difference. Do you think it will matter? I don't load for anything more than having the bullet hit the target close to center, not trying to make one hole with 10 shots.

 

Everything matters, a half a grain is a lot so make fine adjustments until it’s right

 

If your scale is registering +/- the thickness of the zero line and repeating reliably, then I would say you don't have much to worry about unless you are looking for extreme accuracy. Either side of the line is about +/- 10th grain, and as long as you're confident it's reliably repeatable, that's better than most measures will give. If you work up your loads with that scale, what they actually weigh is secondary as long as they are consistent. If you are concerned with accuracy of weight, then checking one uncertified scale against another is not the best way to go. A simple set of grain checkweights from RCBS/Lyman will give you peace of mind.

I've worked on a good many of these simple scales and very rarely find a problem with the agate bearings - they are made of a natural material and I have found, on the very rare occasion, some inclusion or strata line running through one or one slightly miscut off center. It's most unusual to find any wear problems.
The knife edges, on the other hand, are a fairly crudely machined item and very prone to wear and damage, unfortunately, the knife edge is considered an integral part of the beam and will not be supplied as a separate item. At one time, in the event of a problem with the knife edges, RCBS would send out a replacement beam - Now, I understand, they no longer support the older scales, although they probably have a stack of agate bearings, as the same bearing is common throughout the range, 502,505,5-10,10/10, Dillon Eliminator, Lyman M5 etc. with the exception of the RCBS 304 and R130.
This is a handmade knife edge compared to the original example.