Need help with a homemade DC motor

[Adem]

Hey guys
I need help with my homemade DC Motor, as it doesn’t work, pic is uploaded

Thanks

 

[Borek]

Please elaborate on the construction, please elaborate on what is happening when you try to switch it on, you can't expect people to know everything just by looking at one not-too-clear picture.

 

[Adem]

Hey, could the magnet strength be a problem? I’m using ferrite magnets which are pretty weak
Could rare Earth magnets do the trick?

The connection seems to be fine with the coil / brushes / commutator and battery.

 

[Borek]

Everything can be a problem. If you will not give more details you will be just wasting time.

 

[jrmichler]

You need to observe what is happening, then describe it.

1) Does the rotor spin freely when you flip it with your finger? It needs to.
2) Does the rotor pull noticeably when energized? It needs to. The rotor poles need to pass close to the field pieces.
3) Your design does not need permanent magnets to work. A couple chunks of steel will work as well or better.
4) You have a high current, low voltage armature connected to a (relatively) high voltage low current power supply. See my point #2.

I built these type motors a long time ago. They spin really good when you adjust them properly and put enough current through them.

 

[NascentOxygen]

Hey guys
I need help with my homemade DC Motor, as it doesn’t work, pic is uploaded

Hi Adem.
Did you scrape or lightly sandpaper the enamel off the rotor's wire where the paperclip brushes need to make good contact? The varnish on the copper wire is an insulator.

The magnets need to be moved in closer, but I'm sure you have tried that

 

[Adem]

Hi Adem.
Did you scrape or lightly sandpaper the enamel off the rotor's wire where the paperclip brushes need to make good contact? The varnish on the copper wire is an insulator.

The magnets need to be moved in closer, but I'm sure you have tried that

Yeah I’ve done both of them. I’ll change them with better magnets

 

[Adem]

Also my motor is pretty much this motor just with a different battery and different magnets

 

[NascentOxygen]

Is each tower of magnets holding itself together without glue? I think that means you have N-S poles together, so external fields are cancelling. Furthermore, you might have them positioned side on to the rotor, when they need to be end on. Check that. You might also have accidently reversed one of the blocks of magnets to how it needs to be. Best start with a single magnet on each side, get that working first.

You'll need the magnets stacked the way they don't want to stack, and then force them to stay together using sticky tape.

 

[Adem]

Found out the problem, magnets were too weak.
Replaced them with rare Earth magnets and it did the trick.

 

[sophiecentaur]

Found out the problem, magnets were too weak.
Replaced them with rare Earth magnets and it did the trick.

Put them closer together - right by the armature - and the motor will be much more powerful. That basic motor should work ok with simple magnets that were used in school labs.
You will notice that all 'real' motors have an armature with iron in them. That concentrates the field marvellously and will give even more oomph.