Magnetic Parts Trays and Electronic Lathes. Who knew?

[Russell Neyman]

Those small magnetic bowls they sell at the auto parts store are handy, but can cause complications around electronic control systems. I discovered this during some trouble-shooting expedition on my buddy's Jet 1642 EVS, which has an electronic variable speed feature. (What led to this is highlighted in another Sawmill Creek Thread, http://www.sawmillcreek.org/showthread.php?172043-Jet-1442-Lathe-Replacement-Motor).

The idea behind these bowls and trays is that they're a handy place to throw parts and have them not spill. I use one, too, around my lathe when I'm changing chuck jaws. It seems that I drop at least two screws every time I do a changeover, and putting that bowl just below the drive head catches most of them. Dave decided to keep the darn thing on top of his power head, just above the RPM indicator. Suddenly he had a "no power" situation, and the inverter kept shutting down intermittently, and there was a faint humming sound coming from the controls.

We checked everything out, finally realizing that the heavy-duty magnets in the bowl were probably the culprit. Who knew?

[Ken Fitzgerald]

Russell.....a lot of electronics equipments use magnetic sensing for different things........rpms.............position sensing...........

Glad you found the cause!

[Tim Rinehart]

whoa...I guess I'll take the little magnetic tray off top of my headstock...hmmm, good item to point out!

[Alan Zenreich]

I've been using 4" magnetic parts trays all over my shop, including on the headstock of a Nova DVR XP... no problems at all.

[ray hampton]

I keep mine magnetic bowls on the drill press

[Jim Underwood]

I've had no problems with my Jet 1642 doing that.

Course, I cobbed mine together a big speaker magnet, and got the bowl from Sears, in a "two-fer". I spied two bowls mis-packed in one package at Sears, obviously only one had the magnet, but who cares? Sold the good one, and made another for myself. Might be the magnet is different...

[Steve Kubien]

Interesting. I have a DVR and on top of the headstock (which incase you didn't know, houses the motor, spindle, computer...everything but the banjo!) I have one of those Ikea LED gooseneck lights. The light is secured by 3, 1" rare earth magnets. Nova told me themselves that this would not be an issue.

Hmmm.....

[Roger Chandler]

I have one on top of my Grizzly G0698 headstock, and have not had any issues whatsoever..........I think I will find another location for it though...........don't want to take any unnecessary chances.........I put my spindle lock pin and my faceplate screws and my allen wrench set in it.

[phil harold]

*wonders about my light with a magnetic base...

[Ken Fitzgerald]

Folks......lets be reasonable here.

Not every magnet is exactly the same strength. In fact, magnets generally lose strength over time. Beyond that.....the magnetic field of a magnet is polarized and as such aren't always aligned in the same direction. One of the worst problems I ever troubleshot in a laser camera and processor was after I replaced all the thin square magnets used to trip magnetic reed switches at different points within the processor. It turned out the magnets were polarized. They were square, thin and had a tapered hole in the middle for a flathead mounting screw. If you rotated the magnet 90º it wouldn't trip the magnetic reed switch because of the polarization of the magnetic field. Rotate it another 90º or 270º and it worked fine.

Not every electronic circuit contains circuitry that is sensitive to magnetic fields.

My point.....if you aren't having problems...good. But be aware there are electronic circuits that use magnets, magnetic sensors and magnetic switches to control or monitor certain functions. If you bring a foreign magnetic object into close proximity of electronic circuits or components, you could cause a problem.

But nobody is suggesting anybody or everybody will have this happen or ever see it happen.

[Lupe Duncan]

I had a very strong magnet that was used in a high vacuum system penning gauge sitting the side of my lathe.

After a while the dang thing magnetized my toolrest. My gouge no longer would glide smoothly across the rest. I had to de-gouse my toolrest.......DUH. I should have thought about that.