Magnetic Polisher that I designed. For polishing any non-ferrous metal, casting, jewelry, etc.
In response to several people asking about how the magnet polarities are set/arranged, I thought I’d post a comment to discuss the details. First off, the magnets individually need to be polarized through the thickness of the magnetic (i.e. North-south poles are arrange top to bottom, NOT lengthwise.) After that, the magnetics should be mounted on the arbor disk such that the polarities topside alternate N-S-N-S. The magnetics should be arranged such that when rotating they occupy most of the circular region of rotation – if you look at my video, and see the pattern/arrangement, I’ve found that this staggered geometry works EXTREMELY well. Hope this helps everyone! Brian,
LIST OF MATERIALS:
I purchased almost all materials from Ebay (here is the general list):
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Framing is 8020 Inc. Alum. extrusions, (ebay seller 8020incGaragesale)
I used series 1010 aluminum extrusions, and 8020 tri-corner connectors, however I’d
recommend the following joining plates instead:
Ebay, Aluminum 5 Hole “L” Joining Plate 10 Series 4081 ANO (preferred) Price is cheap
too,, or check out these other parts/joining plates:
Aluminum Corner Gusset 10 S 4132 N, or
Aluminum Corner Gusset 10 S 4136 N, or
Aluminum Corner Bracket 10 S 4115 N
Magnets are from magnetics4less (part number: NB057-0-N48, qnty 4), mounted in
staggered configuration N-S-N-S poles. (polarized through thickness, NOT LENGTHWISE)
Motor (Ebay): 90VDC, 1/3HP (or less) is fine. Max RPM is 1750
Motor Controller (Ebay): K&B KBIC-120
Arbor Disk (Ebay): I was able to find a 12″ sanding disk arbor wheel on ebay. However,
grizzly machinery website has a pretty cheap replacement aluminum sanding disc for their
Disc sanding machine. Might want to check out the following link https://www.grizzly.com/products/G7297/parts/MAIN Look at the part# P7297025.
I then cut a circular piece of MDF and mounting that on my alum. sanding arbor. Tapped
pennies on the surface at different locations to balance out the disk. Removed the pennies
and placed wood screws at those locations. Took a LONG time but with patience, it can be
done.
Final Dimensions of the machine: Top surface 11″x11″ and the height of the machine is 13″
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