On and Off Switch for My Low-Volt Pulse Motor (Graphite Balance)

Hook

I finally got the Utron floating on a maglev with donut magnets but the shaking was ridiculous until I started playing with graphite for balance and a clean on and off switch. Small changes really calmed my low-volt pulse motor.

Watch this experiment

Right from the bench you see the Utron spinning on two ferrite donut magnets in the center repelling two on the base. I hit it with 12V, 24V, 36V and 48V. The shaking is constant but at 36V it finds a groove around 400 RPM. You can hear me snort-laugh when it bounces all over the place.

What you'll learn

You’ll see exactly why maglev was needed (hole too big for bearings), how donut magnets behave when you stack them, why 48V under-performed compared with 36V, and the tiny rotor tweaks that let a reed switch and 9V battery fit inside later. All measurements straight from what I captured on camera.

From the bench

I used the same-size Utron twice. One has space for a small sphere inside. The height makes coil placement awkward without printing new parts I can’t afford right now. Gluing a magnet on the outside made it rockier so I peeled it off with alcohol. The center hole lets the magnets catch on the top when you lift it, so disassembly is slow and careful. I got roughly 400 RPM but you can see the unbalance from the donuts inside.

How it works / what we changed

I swapped the little square N52 magnets for ones with more surface area and re-oriented them north-south until the side discs moved smoother. The on and off switch sometimes fires instantly, sometimes needs a nudge. At 12V the middle section spins up fast once the top magnets are stronger. Two donuts top and bottom leave just enough glue-to-magnet gap to scoot. I tried three small center magnets pushing off the stack energy instead of the face itself. That idea still needs testing.

Pulse motor

The Utron never spun great as a plain rotor. It seems to want aluminum and eddy currents to go really fast. I keep trying to put a motor in the middle but dimensions are always just off. Once I shrink the rotor I have here, a 9V battery and reed switch with two-and-two coil setup should drop right in.

Low volt pulse motor

I stopped at 36V because 48V didn’t work as well. Twelve volts already gets the middle section moving nicely. The whole thing runs smoother once balance improves and the on and off switch stays consistent. Low voltage keeps things safer while I dial in the maglev.

Graphite balance

The bearings slide because the hole is oversized so I went maglev. Even then it bounces. I’m planning to add graphite to help with balance and reduce the ridiculous shaking. The new 10mm inner neo rings should also help it bounce back instead of wobbling sideways.

Maglev pulse motor

Two donut magnets inside repel two on the bottom and it finally floats. You can push down and it springs back. I doubt I can eyeball perfect alignment so the center-magnet idea (pushing off the energy in the middle of a double or quadruple stack) is next. The current setup still shakes a lot at speed.

Utron rotor

I have another identical Utron but the inner cavity is shaped for a small sphere. Height is awkward for coil placement. The rotor I’ve been tweaking needs to shrink a bit so everything fits dead center. Gluing magnets outside made it worse so I’m back to internal levitation.

Reed switch pulse motor

Once the rotor shrinks I want a 9V battery and reed switch driving four coils (two and two). That should clean up the on and off switching and give more consistent pulses than the current manual start. I already see the middle section wanting to scream at 12V when the top magnets are right.

Bedini motor

This build sits in the same family as the Bedini SSG style I’ve shown before. The reed-switch version I keep coming back to is basically a simple Bedini-inspired circuit. The goal is the same: clean pulses, back-EMF collection, and smooth rotation once balance is solved.

Pulse motor rpm

I hit about 400 RPM on the current maglev. You can tell it’s unbalanced because the donuts inside make it wobble. With better neo rings, graphite balance, and the reed switch I expect the RPM to climb and stay steadier. The shaking is the main thing killing higher numbers right now.

Donut magnets pulse motor

Two ferrite donuts in the middle and two on the base give nice repulsion but still leave the assembly shaky. I tried pulling one out but then the magnetism drops too much. The new neo rings coming in should replace the ferrites and give tighter control. Magnets sticking to the top of the Utron during disassembly is the biggest hassle with this setup.

Builder checklist

• Two ferrite donut magnets top and bottom (or neo rings when they arrive)
• Check bearing hole clearance before final assembly
• Test 36V as sweet spot before jumping to 48V
• Have alcohol ready to clean glue residue
• Shrink rotor slightly for 9V + reed switch fit
• Stronger wider-face magnets on side discs
• Graphite powder or lube for balance tuning

Troubleshooting

Shaking too much? Add the third small center magnet and push off stack energy instead of face. Magnets hanging on Utron top during lift? Handle slowly and keep other magnets away. On and off switch won’t fire? Check reed or manual contact alignment and try 12V first. RPM stuck low? Balance the donuts better or wait for the 10mm neo rings.

Safety

Magnets snap together hard; keep fingers clear when stacking donuts. 48V didn’t run better but still use fused supplies. Alcohol for glue cleanup needs ventilation. When the rotor is spinning at 400 RPM even on maglev, keep loose clothing and long hair back.

FAQ

Why does 48V run worse than 36V? I don’t have a clean reading on current draw but it just didn’t settle as smoothly on camera. Can I skip maglev? The bearing hole is oversized so it slides; maglev was the quick fix until better rings arrive. Will graphite really help balance? From what I’ve seen on other builds it cuts friction and steadies wobble. Is this a Bedini motor? It’s in the same family once the reed switch and coils go in.

Related on this site

• How to Build a Pulse Motor: Parts, Coil Placement & First Spin
• Pulse Motor Rotor Design: Magnets, Materials and Balance
• I Finally Got My Pulse Motor Running (Reed Switch)
• Magnetic Levitation with Six Donut Magnets
• Minor Adjustments, Major Results — Pulse Motor Optimization

Watch this experiment on YouTube

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