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Cake lady needs help to simulate record player


#1

Hi everyone,

It’s 2am here in Australia and I have hit a wall.

I’ve been trying to figure this out for ages: What battery operated motor I should use to simulate a record turning speed for a record player cake I want to make my bonus daughter for her birthday.

I just don’t know enough to know what to choose.

Can someone please help me…?
The chocolate “record” might weigh anywhere from 500g to 1kg and would be all that sits on top of the motor.

I promise to share pics if I get this thing going!

Cheers x


#2

Hello.

The gearmotor you choose should be based on the specific requirements of your application. If you know your torque and speed requirements, I might be able to make a suggestion. If you are not sure what your torque requirements are, you might find this blog post on force and torque helpful.

By the way, its not clear from your post, but you should probably make sure the full weight of your cake and platform is not on the shaft of the gearmotor. You might consider using a load bearing mechanism like a Lazy Susan to take the weight off the shaft of the gearmotor. Doing so will also allows the geamotor to drive the platform without having to be centered under the platform. For example, the gearmotor could be placed farther out from the center and drive the spinning platform from underneath using a wheel.

Grant


#3

Thanks Grant. I’ll check that out.

I don’t plan to have any actual cake on top of the motor, only a chocolate record.

I just popped in to update the post with at least the rpm I desire. 30rpm with the 500g to 1kg (1 to 2 pounds, I think) would do nicely.

The dimensions would be 12.375 in ( 31.43 cm ) square (but round, haha).

I’ll go see if I can figure out the torque now.

Cheers,
Rochelle


#4

Ok, I read & understood about half of the information you directed me to.

I don’t understand the material enough to know how to calculate what I want to do, though.

Thanks for trying to educate me. It was a nice brush up in some theory I haven’t looked at in over 20 years. I actually liked physics at high school.

Given that, is there anyone that can recommend a direct drive motor application where I can sit I 500g to 1kg (1 to 2 pound) record on top of the battery powered motor (mounted to a small [5g] lightweight plastic plate) with 12.375 in ( 31.43 cm ) square dimensions at 30rpm…?

Cake decorators all over the world are searching, in vain, for such an application. Just look up how many “record player cakes” are on YouTube or Pinterest.

If we can figure this out, there could be quite a number of sales as a result.

Best wishes,
Rochelle


#5

We do not have the maximum axial load of our gearmotors well characterized, so we are not entirely sure how appropriate it would be to use our gearmotors to support the full weight of that disc in the way it sounds like you are describing (i.e. the axis of rotation of the motor output shaft is aligned with the center of the chocolate disc). However, if you want to try, one of our larger form factor gearmotors, like the 25D or 37D gearmotors, is probably more likely to be able to support the weight of your disc. If that is something you want to do, and if you are planning on aligning the output shaft of the gearmotor with the center of your disc (i.e. point the motor upright with the disc centered on top of it), you can just pick a gearmotor that has a no-load speed that is close to the target speed you want to achieve. Keep in mind, however, that the actual speed you get will be lower when you add a load to the gearmotor.

Grant


#6

Thanks again, Grant.

I think I’ll try #1588 172:1 Metal Gearmotor 25Dx56L mm LP 6V

Would you like to know how I get on with it?

I’ll try this one now, and get a low rpm high power next time if this one doesn’t have enough torque.

Thank you for all your help. You were correct in your assumptions and very helpful.

I am grateful for your guidance.

Kind regards,
Rochelle


#7

Of course! We would love to hear how it works out for you! Feel free to share it in the Share your projects section of our forum.

Grant