Magnet coil cores, demagnetization power and Lenz delay.

[synchro1]

R2-5-2RS Full Ceramic Bearing 1/8"x5/16"x9/64" inch ZrO2 Bearings

Price: $46.88

This is the same bearing without the flange: Total cost for the 2 bearings and the 1" tube magnet $116.53

Here's the link:

http://www.vxb.com/page/bearings/CTGY/1-8inch

Here's the link for the tube magnet:

http://www.kjmagnetics.com/products.asp?cat=16

This small investment of $116.53 will put in the Hyper-Sonic RPM speed range. Don't neglect the "PVC coupling" safty housing!

The trick to mounting these bearings is First: Avoid glue!

Just sand each end of the 1/8" brass axle, and leave a thicker portion in the center for the bearings to squeeze onto. The magnet was pre-sanded to squeeze fit the OD and it all pressure fits. When your're ready the axle pushes through one side of the PVC coupling, the magnet slides on then one bearing, then the axle pushes through the other side to slde the other bearing on then it all press fits in the center. A bit of craftsmanship required. You won't regret it. A tiny push rollllllllls on seemingly forever!

A small air core series bifilar power coil, a Reed switch and a DPDT throw switch and you'll be in for the thrill of a life time with the "Hyper Speed Burst"!

[Pirate88179]

FR2-5-2RS Full Ceramic Flanged Bearing 1/8"x5/16"x9/64" inch ZrO2

Price: $173.49

Magnet ring.

Dimensions: 1" od x 1/4" id x 1" thick
Tolerances: ±0.004" x ±0.004" x ±0.004"
Material: NdFeB, Grade N42
Plating/Coating: Ni-Cu-Ni (Nickel)
Magnetization Direction: Diametrical
Weight: 3.19 oz. (90.5 g)
Pull Force, Case 1: 40.44 lbs
Pull Force, Case 2: 49.01 lbs
Surface Field: 6909 Gauss
Brmax: 13,200 Gauss
BHmax: 42 MGOe

These rings are diametrically magnetized, which means they are magnetized perpendicular to the axis of the hole. The poles are located on opposite sides of the circular faces. They can be placed on a shaft to work with sensors or to generate electricity.

2 ceramic bearings  $346.98. One 1" neo tube  $22.77 Total cost:  $369.75

These bearings are a Little over sized. Sanding the bore hole just a tiny amount will allow these ceramic bearings to pressure fit just right. A brass rod can sand down just enough also to squeeze through the 1/8" ID bearing hole.

Good luck sanding the I.D. of those bearings as that material is harder than the material used on your sandpaper.  You could use specialized diamond paper, but it is very expensive.  A properly sized diamond reamer would be the most cost-effective way to do this.

Bill

[Paul-R]

Good luck sanding the I.D. of those bearings as that material is harder than the material used on your sandpaper.  You could use specialized diamond paper, but it is very expensive.  A properly sized diamond reamer would be the most cost-effective way to do this.

Bill

It might  pay to  hire - or ask  a machine shop how much they charge per hour.

[synchro1]

It might  pay to  hire - or ask  a machine shop how much they charge per hour.

@Pirate88179,

The OD of the bearing is 5/16". The ID of the magnet tube is 1/4" that means the bore hole in the magnet needs to be enlarged by approximetely 1/32" and it's the magnet not the bearing I'm refering to. Sorry if I confused you. It might help to drill it out. Same goes for the bearing ID of 1/8". Assuming the brass axle rod is also 1/8", the brass rod needs to be be sanded, not the bearing. I would put tape at the ends where the magnet lines up and use a block to butt the rod up against then attach an electric drill to rotate it in a sandpaper sandwich. That would leave a full 1/8" thick section the length of the tube magnet in the center of the brass axle. Now the ends of that might need a tiny reduction, because lateral pressure on those bearings is potentially destructive. Any pressure needs to be applied to the base or the top of the bearing casing, depending on where the squeeze joint is. The flanged bearing might be safe to glue.

Just the vapors alone from some kinds of glue is enough to degrade the perfection of the precision ceramic balls. Once securely mounted, these kinds of ceramic bearings have extended longevity.

[Pirate88179]

@Pirate88179,

The OD of the bearing is 5/16". The ID of the magnet tube is 1/4" that means the bore hole in the magnet needs to be enlarged by approximetely 1/32" and it's the magnet not the bearing I'm refering to. Sorry if I confused you. It might help to drill it out. Same goes for the bearing ID of 1/8". Assuming the brass axle rod is also 1/8", the brass rod needs to be be sanded, not the bearing. I would put tape at the ends where the magnet lines up and use a block to butt the rod up against then attach an electric drill to rotate it in a sandpaper sandwich. That would leave a full 1/8" thick section the length of the tube magnet in the center of the brass axle. Now the ends of that might need a tiny reduction, because lateral pressure on those bearings is potentially destructive. Any pressure needs to be applied to the base or the top of the bearing casing, depending on where the squeeze joint is. The flanged bearing might be safe to glue.

Just the vapors alone from some kinds of glue is enough to degrade the perfection of the precision ceramic balls. Once securely mounted, these kinds of ceramic bearings have extended longevity.

Ah, I see...never mind.  It is entirely possible that it was I that misunderstood you.  Ceramic bearings are great, and there are, of course, various grades.  I have found that the ones sold for skate boards and roller blades are actually pretty good and about 1/3 of the price you mentioned.  If yours is a higher precision than, that would make sense.

Bill