Oscillating Reed Switch Pulse Motor.

[Allen Burgess]

Scope.

@Matthew Jones,

I'd love to see the "Reed oscillator" on a scope! Thanks for solving the coil Ohms for #26 ga magnet wire to match the .5 amp Reed switch current rating problem. You gained my complete confidence with that important amount of math, and put the replication on solid ground. I couldn't help with that critical information. I'm sure my coil was wrongly wrapped, because it burned too many switches out!

[OrionLightShip]

@Matthew Jones,

I'd love to see the "Reed oscillator" on a scope! Thanks for solving the coil Ohms for #26 ga magnet wire to match the .5 amp Reed switch current rating problem. You gained my complete confidence with that important amount of math, and put the replication on solid ground. I couldn't help with that critical information. I'm sure my coil was over wrapped, because it burned too many switches out!

I think that the reason you survived with so little wire, Allen, is due to impedance at frequency. If you survive the initial inrush current, the inductive reactance adds to the dc resistance value which gives the total impedance.

[Turion]

Where did yu guys find the ceramic bearings for this?

Dave

[Allen Burgess]

Where did yu guys find the ceramic bearings for this?

Dave

@Turion,

Please look at comment #13 on page 1:

Boca Bearing Company :: Ceramic Bearing Specialists

Popular Searches | Boca Bearings

[Allen Burgess]

24 gauge: 0.0201 (0.51054 Ohms per thousand feet) 25.67 84.1976 3.5 (0.577 amps) 68 kHz (11.5 lbs per thousand feet):


Maybe it would help to increase the coil wire thickness from 26 to 24 gauge? The gold wire in the Radio Shack assortment package.

[OrionLightShip]

24 gauge: 0.0201 (0.51054 Ohms per thousand feet) 25.67 84.1976 3.5 (0.577 amps) 68 kHz (11.5 lbs per thousand feet):


Maybe it would help to increase the coil wire thickness from 26 to 24 gauge? The gold wire in the Radio Shack assortment package.

larger the gauge.....smaller the wire diameter....higher the resistance

[Allen Burgess]

Wire resistance.

larger the gauge.....smaller the wire diameter....higher the resistance

@OrionLightShip,

Would it help to raise or lower the wire resistance to protect the .5 amp rated Reed switch? I never applied any math to the coil, just intuition. Maybe 26 ga is just right! I think it's a good idea to keep the diameter of the coil small.

[OrionLightShip]

@OrionLightShip,

Would it help to raise or lower the wire resistance to protect the .5 amp rated Reed switch? I never applied any math to the coil, just intuition. Maybe 26 ga is just right! I think it's a good idea to keep the diameter of the coil small.

Well, there are several parameters to consider here but I think the answer will be found on the bench and no one better qualified to figure those things out than Matt. I'm certain all of our questions will be answered once he has had time to put this together and given some time to run it.

[Allen Burgess]

Ceramic vs Steel bearing comparison.

@Turion,

Check out this steel to ceramic bearing comparison video:

https://www.youtube.com/watch?v=X2KCs_lBKWU

[Matthew Jones]

I am thinking of raising it. I have some 28 handy and at 185 foot you are right at 12 ohms. at 12.5 volt that gives you about 1 amp on the surge. 25 volt will net 2 amp and add about 65% more speed.

But I also have another motive and that is to see if the reed is faster than a transistor. Some one said they bet it was....who was that? We'll see. I know they are not faster than a hall switch. But we'll see about that as well.

Everything should come next week and I have all the design work done. I am going to try to get things milled and fit tomorrow and finish when the magnets come.

See ya then.
Matt

[Matthew Jones]

Just a little update... I am working on this over the holiday and I am about done with the mag bearings.

https://youtu.be/L2Ha2buhLjs

Cheers
Matt

[Allen Burgess]

Mag bearings.

@Matthew Jones,

Awesome Matt! You manufactured those by hand? I hope they work as well as they look!

[Matthew Jones]

@Matthew Jones,

Awesome Matt! You manufactured those by hand? I hope they work as well as they look!

No I modeled them and cut them on the CNC. David (Turion) bought a CNC a while back and sent it to me because I have all the 3d / cad background. He's getting another sometime so I can just email him files to replicate. We both have the same 3d printer also, but neither one of us has put them together yet.

The bearings will work when its all done and assembled I am going to design up and cut everything today and the diametric will be here Tuesday. I have everything I need to put it together. I have ordered a tach but I don't know when its coming, but I can put a scope on it and find the rpms.

I'll update again before Tuesday.

Matt

[OrionLightShip]

Just a little update... I am working on this over the holiday and I am about done with the mag bearings.

https://youtu.be/L2Ha2buhLjs

Cheers
Matt

Wow! My first look at mag bearings was with skycollection's videos. This is so much more advanced! Really nice....bet that thing will zing

[Allen Burgess]

Mag bearings.

The most obvious drawback, compared to the internal ceramic bearings, is the addition of the larger 1/4" brass axle that has to turn along with the magnet tube.