RCBS 505 problems

Lead hammer

Lead hammer

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oh goodie. My 505 after 10+ years, is totally wonky. I assumed I just needed to clean the contact points with alcohol, and I thought it worked, but after more testing it appears to weigh lighter and lighter until the beam rests on the lower stop. Any ideas out there??

Ok, cleaned it again, now seems to be working. Weighed a coin 10 times, then after it returned to zero. Strange as it appeared clean, made a fine piece of hair or fuzz or something in it I need to buy a computer air duster thing to do better upkeep on it maybe.
 
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It's a balance beam - if it stops balancing/zeroing, then weight has somehow been added to one side of the beam or taken off the other side.

All three weights are on zero? The brass tray is in place in the aluminum cup? Nothing damaged or missing? If it all appears to be there, I would give the beam and all the components on it a gentle but thorough scrubbing with a toothbrush and cleaning liquid. The only balance beam scale I've seen go wonky was sitting in a garage for years, exposed to exhaust and cigarette smoke so it had a film of tar residue on the beam and weight surfaces. Cleaning fixed it.
 
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Did you calibrate the scale?

Lay the scale on your bench, zero out the scale. If it pointer is not zeroed/balanced, use the level leg on the left side of the unit and dial it up/down until the pointer is zeroed.
 
Lead hammer said:
oh goodie. My 505 after 10+ years, is totally wonky. I assumed I just needed to clean the contact points with alcohol, and I thought it worked, but after more testing it appears to weigh lighter and lighter until the beam rests on the lower stop. Any ideas out there??
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Find a way to get rid of all that static. Wash the entire scale with dish soap and let it air dry.
 
Yes i have upgraded the metal pan for a plastic one years ago, added weight to the counterweight to compensate, and used my RCBS check weights to confirm. This was 5-6 years ago. It has bee really good and sensitive, as in I can look at the pointer, and know one or two more kernels of H4350 is needed to balance. Today was 7 kernels to get the pointer to move. Freaked me out lol.
 
Lead hammer said:
Yes i have upgraded the metal pan for a plastic one years ago, added weight to the counterweight to compensate, and used my RCBS check weights to confirm. This was 5-6 years ago. It has bee really good and sensitive, as in I can look at the pointer, and know one or two more kernels of H4350 is needed to balance. Today was 7 kernels to get the pointer to move. Freaked me out lol.
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dirty, or static
 
The 505 has magnetic dampening doesn't it? is it possible that a magnet reversed polarity in the dampening system, or would that make any difference. Probably not....?
 
10 plus yrs of steady use very well could have wore the groove in the "beam pivot point" to be an unpredictable condition. I had one do this years ago, at that time RCBS offered replacement "divots", they weren't made of as hard material as the beam pivots (hardened steel) so they did wear instead of the pivot.
 
Snider shooter said:
What about plastic items near scale,I've had scales go wonky from a die box behind scale. Creates static electricity. I always have a second scale to double check periodically. Had one pick up 2 pieces of cat hair,never hurts to clean.
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I'm certain it must have been cat hair, and or dust. I'm going to try it again here now that supper is over. Everything is the same on my bench since forever, except for an old wooden ammo box. I had thought that might have been it and removed it, but it did the same thing. I should make a nice wood cover for it to keep it clean.
 
Lead hammer said:
I'm certain it must have been cat hair, and or dust. I'm going to try it again here now that supper is over. Everything is the same on my bench since forever, except for an old wooden ammo box. I had thought that might have been it and removed it, but it did the same thing. I should make a nice wood cover for it to keep it clean.
Click to expand...

Trust me. Wash it in warm water with dish soap and let it air dry. I bet it works. It will eliminate/reduce the static that the beam has accumulated, even if only for a while.

Keep us posted...
 
Lead hammer said:
I'm certain it must have been cat hair, and or dust. I'm going to try it again here now that supper is over. Everything is the same on my bench since forever, except for an old wooden ammo box. I had thought that might have been it and removed it, but it did the same thing. I should make a nice wood cover for it to keep it clean.
Click to expand...

RCBS will send you new bearing blocks if you phone them as I had to for my RCBS 505 and Ohaus 10-10. Made a big difference. Keeping it covered is a good idea and I use a Tupperware box that I can put 505 in with a lid or just put it over the scale.
 
4n2t0 said:
Trust me. Wash it in warm water with dish soap and let it air dry. I bet it works. It will eliminate/reduce the static that the beam has accumulated, even if only for a while.

Keep us posted...
Click to expand...

I have not washed it yet, just the alcohol swabs on the bearing blocks. (did it twice, but I will try the wash thing next go around thanks) I did load up 10 test rounds and everything is back to normal, one grain movement again and held zero.
I should maybe get some bearing blocks just to have on standby maybe. Thanks Reeferman for the idea.
 
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