Thread: Trouble with scales

Hi team,

I’ve been having slight dramas with my RCBS beam scale and not sure what, if anything, I can do about it.
Typically I throw into the pan and put on scales like we all do, but the beam seems to do random shit. Sometimes it floats freely and I add the desired power trickle to top it up and bam I’m in the money.

But lately it kinda swings up then down then just sticks. Everything seems clean and free moving but is there something I could be missing?

The beam has a knife edge axle that sits in ceramic vee blocks. A build-up of dust there can cause problems. Once cleaned, your scales should live under a dust cover when not being used.

I had a similar problem a while ago, had a look and the axle was ever so slightly out of square on one side. Carefully straightened it with a pair of pliers and back to being responsive and accurate. Mine looks like it may have got bent in shipping.

I had a set of Redding scales that were becoming a little less reliable. The following gave me excellent results.
Using a small artists paint brush, remove all dust.
Clean the V and brush on some graphite.
Sharpened the knife edge (very carefully with a small and extremely fine oil stone.
Replaced the magnets with stronger ones. This will not effect the accuracy but will reduce the time it takes to settle.
https://en.m.wikipedia.org/wiki/Magnetic_damping

After zeroing I have 2 check weights. About 40 and 100 grains. With these you can check, 40, 100 and 140gr. I use these to ensure the scale continue to be consistant. They should never change. Anything will do. Three nuts or bolts for example.

Another tip with beams is to not leave it "on balance" i always take the beam out of its pivot. Just so it doesnt wear excessively...... mostly it sits on the shelf these days but always there for a refference if needed. But imagine if its done 20 years of pivoting 24 / 7

Thanks for the advice. One thing I didn’t consider which I will now do is actually put it away.