Lyman scale issue

Discussion in 'Reloading' started by Texas Republic, Aug 3, 2012.

  1. Texas Republic

    Texas Republic Well-Known Member

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    Aug 27, 2009
    Lyman Pro 500 weighted scale

    My reloading process is basically charging through a RCBS powder thrower....then placing the charge on my Frankford digital scale to get it where it should be.....then placing it on my Lyman scale to double check the charge. The charge between the digital and weighted scales almost always matches. However, here lately the Lyman has been inconsistent by about 4 actual pellets. I guess about .04 grns.

    I know its the Lyman because I can place the charge on it and it will show a little too heavy. I take it off and put it right back on and it will be closer to a match. I take it off again and place it back on and it will finally be a match. Why is it changing? I am leaving it on for plenty of time. I have checked the zero while its doing this and its fine. It seems to be something else. I cant imagine what. Its not that complicated of a mechanism.

    I have already experienced the air conditioner issues and its not that. Its on a desk top that is fairly level. Its not PRECISELY level, but I didnt think it would matter that much. Besides, it just recently started doing it.

    I am not super delicate when I place it back in its drawer. Perhaps something got rattled around too much?

    Any suggestions?
     
  2. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    May 13, 2012
    static electricity or dust.
    I don't even bother to cover my scale-- I just blow the dust off as it accumulates because the dang covers out there are plastic and may transfer static charge. I also use hepa type filters on my furnace, but that's mostly a allergy thing, and the scale not getting dusty is a secondary benefit. Use check weights on both scales if you have issues.
     

  3. boomtube

    boomtube Well-Known Member

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    Oct 8, 2007
    Clean the "V" bearings and knife edges. Make sure the pivot bar ends aren't rubbing against a bearing retaining clip. Insure that you don't have a spider web thread somewhere in the magnetic damping slot. Remove the beam from the body when you're storing the scale to prevent damaging the critical pivot knife edges; it's a precision instrument, not an anvil, and is susceptable to damage from rough handling.

    The beam scale will be more accurate, more sensitive and will follow your trickler much better than most digitals. And it will last MUCH longer if you take care of it. Plus using it will be just about as fast as a digital IF your scale and measure location and work flow path is right.

    It's easy for noobs to suppose they are doing 'precision' reloading if they are counting kernels of powder but if the load is properly developed that's really not critical, a good load will have a charge tolerance of several tenths on each side with no perceptable difference on target.
     
  4. Texas Republic

    Texas Republic Well-Known Member

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    I think the problem may lie in the V shaped pivot. Not exactly what it is though. I notice that the beam rotates on the plastic grooves and sometimes gets farther to one side if that makes sense. I'll read the assembly instructions again and make sure it looks right. Thanks fellas
     
  5. boomtube

    boomtube Well-Known Member

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    I think you'll find the "plastic grooves" to be agate and letting the beam slide to the front or rear so the axle rubs on the bearing clips will interfer with movement. If you've dulled/burred the knives that will also inhibit movement.