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Thread: softening edges of mag rods

  1. #1
    Tone Mechanic
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    softening edges of mag rods

    I got this image off of Seymour's site. I've also seen them doing this in their dvd switching out the mag rods with a keyless chuck.

    What is the material that they're using on the machine to soften the edges of the magnetic rods?

    It looks like a buffing pad even though i believe it isn't.
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    It looks like a grinding wheel (to put a slight beveled edge on the magnets), but that's just a guess.

    DoctorX

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    Pickup Maker David Schwab's Avatar
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    That looks like a grinder... the wheel looks like the kind they use for sharpening, like a wet stone.
    It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. Albert Einstein

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    Poke my nose in guys but there is grooves in that wheel so may be a white bauxite stone or even a hard felt pad with some form of grinding paste being lifted from the receptical a the bottom. If it's a wheel then probably water but thats not a sealed motor so not sure there. The keyless job is prob turning under its own power rather than manually so as to keep the grind even. This has come up before by Possom and when it did I did do and experiment that did actually work. I did it with round bar but square or whatever will do. One drilled slightly oversize mag hole in each end and dropped a mag and a touch of superglue down each hole. You can now hold the mags different poles of course against a fine grindstone. Works a bit like a centreless grinder but only using one wheel and the mag spins in the opposite direction to the wheel and you can get a very even chamfer. Hand spinning it with a keyless chuck takes a very steady hand or a stop to work against. Quick change jobby as well. Super cheap nowt to buy really.
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    Oooops sorry the superglued mags stay in there they keep the ones you are grinding held in place. Didn't come out so worked a treat.

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    Quote Originally Posted by jonson View Post
    The keyless job is prob turning under its own power rather than manually so as to keep the grind even. This has come up before by Possom and when it did I did do and experiment that did actually work.
    yep...I remember when possum inquired about the keyless chuck.

    .....in the dvd/video it shows a worker inserting a rod into the chuck, spinning it on the wheel via a cordless screwdriver, and then releasing it and then inserting another one. He was quite proficient at it. It looked as if was a millwaulkee cordless screwdriver.

    would love to know exactly what the material is on the wheel.

    you mentioned you used a grinding stone? .....is there a specific grit number for the grinding wheel that you used? It would seem that it would have to be very fine as to not dig deep into the metal thus marring it, as well as not taking too much off of the edges.

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    Pickup Maker David Schwab's Avatar
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    It's probably something like this:
    Japanese Water Stone Wheels

    Or some other kind of Arkansas stone wheel like you would use for sharpening chisels and stuff.
    It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. Albert Einstein

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    Just looked at that vid and is deff a white probably bauxite stone. Have'nt seen jap stones as wheels although they are prob out there. Game with them is as you stone the worn grit fills the stone and it gets finer till you water flush it but they would wear quick as they are soft. will look in the cupboard for what I used and get grit no and make sure what the composition was.

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    low tech

    I just use a cheap Harbor Freight disc sander, the sand paper wears out you replace it. In that photo you can see the magnet has worn a groove in the stone. His keyless chuck looks like its a quick use type you snap it in and ready to go, would love to know where to find that rig they are using, I did get a keyless chuck but as usual its cheap chinese made, not real stable
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    Quote Originally Posted by kevinT View Post
    I got this image off of Seymour's site. I've also seen them doing this in their dvd switching out the mag rods with a keyless chuck.

    What is the material that they're using on the machine to soften the edges of the magnetic rods?

    It looks like a buffing pad even though i believe it isn't.
    It's a grinding wheel made of aluminum oxide, which is the industrial standard for grinding High Speed Steel (used to make drill bits, end mills, and the like).

    Such wheels are widely available from industrial suppliers.

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    Pickup Maker David Schwab's Avatar
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    Quote Originally Posted by Possum View Post
    I just use a cheap Harbor Freight disc sander, the sand paper wears out you replace it. In that photo you can see the magnet has worn a groove in the stone. His keyless chuck looks like its a quick use type you snap it in and ready to go, would love to know where to find that rig they are using, I did get a keyless chuck but as usual its cheap chinese made, not real stable
    I just realized we have two of those cordless drill drivers at the shop. I recognize the red body with the black ring. It looks like they stuck some kind of plastic tube over the end, maybe with a magnet glued it to hold the magnet they are grinding.

    I forget what brand the drill drivers are, but I'll look this Sunday when I'm there. They are brand name, and about 15 years old. Don't think they are made anymore. The batteries are shot so we don't use them anymore.
    It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. Albert Einstein

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  12. #12
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    here is a link to one product option.


    http://www.rockler.com/product.cfm?O...Select=Reviews


    "Made of granulated aluminum oxide with a vitrified white bond, which allows the grains of abrasive to wear off, providing a consistently fresh grinding surface."......that explains the grooves in the wheel that possum mentioned.

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    Both you guys are right, Checked my wheels this morn and the white ones are Aluminium Oxide but I did a Possom and did the same job on a disc sander and a belt sander with no probs apart from wear. They are soft bonded the White wheels but very hard and my fine one I used originaly is 120grit but catalogue check says they go to 600grit but not on the same scale as paper abrasives. Guess it's make use and work with what you've got.

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    Quote Originally Posted by kevinT View Post
    "Made of granulated aluminum oxide with a vitrified white bond, which allows the grains of abrasive to wear off, providing a consistently fresh grinding surface."......that explains the grooves in the wheel that possum mentioned.
    This is true of all grinding wheels, regardless of what they are made of. The rule of thumb is to use a soft wheel on hard materials. The reason is that hard materials blunt the edges of the abrasive gains faster, so to maintain cutting effectiveness it's best if the blunted grains break out of the wheel, exposing fresh, sharp grains.

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    Pickup Maker David Schwab's Avatar
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    Here's the cordless driver in the Duncan picture... it's a Milwaukee.
    Attached Thumbnails Attached Thumbnails milwaukee.jpg  
    It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. Albert Einstein

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    Those screwdrivers aren't cheap a HF 12V drill would do a fine job here for $9.99. I can understand why one would chamfer magnets by hand when you can order them that way for an extra .07 ea. I think a buffing wheel makes more sense but that would turn dark right away so the photo must be of a fine grit grinding wheel. I'd get a 400 or 600 grit for this job.

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    Pickup Maker David Schwab's Avatar
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    Quote Originally Posted by David King View Post
    Those screwdrivers aren't cheap a HF 12V drill would do a fine job here for $9.99.
    Yeah I don't know why they are using those. They are old too and the batteries don't last. We have 4 of them sitting in a drawer.

    Maybe because they are slim and easy to hold?
    It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. Albert Einstein

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    Wet-Stone

    Try just putting the magnet in the end of a drill and tighten. After it is inserted like a drill bit... hold the drill at a 45 degree angle and use a wet-stone with a little oil to soften the edge. In my opinion that is the Cheap Way to get results... Since you have a drill laying around and a wet-stone that costs about $5-$6 there you have it.. beveled edges ... There is no reason to use a (rig) of 2-3 different tools that you have to buy to do the job -Chris KP

  19. #19
    Pickup Maker David Schwab's Avatar
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    I was thinking the same thing... but chuck it in a drill press. You can made up a jig to hold the stone at the correct angle.

    Chinese made bench top drill presses go for about $50....
    It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. Albert Einstein

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  20. #20
    ken
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    I use a grinder with a soft stone, and a modified large Xacto red plastic cutter handle to hold onto the magnet. I use the handle because I ground the end off one of my fingers once when my wife surprised me when I was beveling.

    I tried the drill chuck method, but I don't because I don't want to get grit
    in my drillchuck and wear it out.

    Ken

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