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Rifles, Reloading, Optics, Equipment
Reloading
Looking to upgrade my balance, suggestions?
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<blockquote data-quote="milanuk" data-source="post: 288415" data-attributes="member: 376"><p>And... I disagree in turn <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink ;)" loading="lazy" data-shortname=";)" /> Reluctance is not an 'effect' from moving through a magnetic field, it is a *property* of the material, whether conductor or non-conductor which represents the opposition of the material to magnetic lines of flux. Mathematically it varies directly with the length of the flux path in centimeters and inversely with the cross-sectional area and permeability of the material (at least according to the electrical primers I have on my shelves).</p><p></p><p></p><p>And... this gets to the heart of where we disagree, I believe. As I mentioned before... based on my training & past experiences working with reluctance motors (like control rod drive mechanisms for certain flavors of nuclear reactors), granted as a 'tech', not as an engineer... reluctance can be used to provide motive force, albeit at relatively low torque values, or in the case of these scales, to slow down & stop motion. From the manual for a 10-10... "it operates on the principle of a permanent magnetic field resisting the motion of a non-magnetic, copper damper vane attached to the beam." There is no magnetic field being induced in the copper vane, no significant circulating (eddy) currents generated. Just the reluctance of the non-magnetic vane to the magnetic flux of the two sets of magnetic poles in the slot creating some resistance to its motion. Normally the reluctance of copper is very, very high as compared to iron or sheet steel (like the laminations used in xfmr cores and pole pieces for motors or generators) - but compared to air, it is somewhat lower. Given that there are two sets of poles they are probably set up so that they oppose one another - so as to simply encourage the vane to *stop*, rather than push it one way or another.</p><p></p><p>As for the tendency of the vane to want to 'stick' to one side or another... I agree, it *shouldn't* be capable of building up any residual magnetism (being copper and all that). Likewise it *shouldn't* be capable of generating or retaining static charges, being made primarily of metal - iron, copper, aluminum, etc. In that regard I'm simply reporting on what I've *seen*. But... here's a thought for ya... we have a metal beam, and a metal scale body. What separates the two? Air on the one end, and agate bearings on the other - I'm not entirely sure how conductive agate (member of the quartz family) is? Two conductors separated by an insulator makes a... capacitor, capable of storing static charges. Really going out on a limb on that one, but the usual explanations (debris of some sort in the knife bearing surface areas) don't fit when I've cleaned the heck out those regions and seen the scale start to pull over to one side over time. I don't have that particular scale anymore, and my current 10-10 doesn't seem to have the same 'issues' so who knows? <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite8" alt=":D" title="Big Grin :D" loading="lazy" data-shortname=":D" /></p></blockquote><p></p>
[QUOTE="milanuk, post: 288415, member: 376"] And... I disagree in turn ;) Reluctance is not an 'effect' from moving through a magnetic field, it is a *property* of the material, whether conductor or non-conductor which represents the opposition of the material to magnetic lines of flux. Mathematically it varies directly with the length of the flux path in centimeters and inversely with the cross-sectional area and permeability of the material (at least according to the electrical primers I have on my shelves). And... this gets to the heart of where we disagree, I believe. As I mentioned before... based on my training & past experiences working with reluctance motors (like control rod drive mechanisms for certain flavors of nuclear reactors), granted as a 'tech', not as an engineer... reluctance can be used to provide motive force, albeit at relatively low torque values, or in the case of these scales, to slow down & stop motion. From the manual for a 10-10... "it operates on the principle of a permanent magnetic field resisting the motion of a non-magnetic, copper damper vane attached to the beam." There is no magnetic field being induced in the copper vane, no significant circulating (eddy) currents generated. Just the reluctance of the non-magnetic vane to the magnetic flux of the two sets of magnetic poles in the slot creating some resistance to its motion. Normally the reluctance of copper is very, very high as compared to iron or sheet steel (like the laminations used in xfmr cores and pole pieces for motors or generators) - but compared to air, it is somewhat lower. Given that there are two sets of poles they are probably set up so that they oppose one another - so as to simply encourage the vane to *stop*, rather than push it one way or another. As for the tendency of the vane to want to 'stick' to one side or another... I agree, it *shouldn't* be capable of building up any residual magnetism (being copper and all that). Likewise it *shouldn't* be capable of generating or retaining static charges, being made primarily of metal - iron, copper, aluminum, etc. In that regard I'm simply reporting on what I've *seen*. But... here's a thought for ya... we have a metal beam, and a metal scale body. What separates the two? Air on the one end, and agate bearings on the other - I'm not entirely sure how conductive agate (member of the quartz family) is? Two conductors separated by an insulator makes a... capacitor, capable of storing static charges. Really going out on a limb on that one, but the usual explanations (debris of some sort in the knife bearing surface areas) don't fit when I've cleaned the heck out those regions and seen the scale start to pull over to one side over time. I don't have that particular scale anymore, and my current 10-10 doesn't seem to have the same 'issues' so who knows? :D [/QUOTE]
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Reloading
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