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Mechanics and Construction => Mechanics and Construction => Topic started by: rhysonic on April 10, 2018, 05:47:58 PM

Title: Very quiet, high torque 150rpm motor advice
Post by: rhysonic on April 10, 2018, 05:47:58 PM
Hi I am designing a musical percussion instrument based on a spinning wheel. I have been using a power drill to spin the wheel, but when I try to record in in a studio or if I am on a really quiet stage the sound of the power drill really stands out.
Here is a video of an older version of the instrument (using a drill)
[youtube]https://www.youtube.com/watch?v=0vQQ4R0w9gM[/youtube]

I have bought a couple motors recently but have had issues with all of them. This one for example, is a bit heavy, has quite a bit of low hum especially when mounted in a wooden box, also the amount of torque it has is I suspect overkill. I have had to put it in a box, inside a box, inside a box to reduce the vibration hum :(
https://www.groschopp.com/product/brushless-dc-gear-motor/parallel-shaft/?id=4840 (https://www.groschopp.com/product/brushless-dc-gear-motor/parallel-shaft/?id=4840)

This other (crouzet dcmind) very quiet motor I bought recently is a bit small and doesn't have enough torque
https://www.digikey.com/product-detail/en/crouzet/89810008/966-1684-ND/6137254 (https://www.digikey.com/product-detail/en/crouzet/89810008/966-1684-ND/6137254)

I can explain the amount of torque I need like this: If I pinch the rotation shaft really hard between my index and thumb and I can slow it down by no more than 10 percent then it probably has enough torque

The dcmind motor spins at 3000 rpm which is way too fast, but when I lower the voltage to 3.5v it gets down to maybe 300 rpm, but when I give it the pinch test I can stop it completely.

I really don't want to use a geared motor if I can avoid it ( I know this is wishful thinking) because I absolutely want the motor to be as quiet as possible so that I can record in the studio with it.
I am not sure if maybe stepper motors are quieter?
or maybe there is a special gearbox I could attach to the dcmind motor which would be quiet enough?
Also if anyone has any advice about sound insulating the motor that would be appreciated :)

Thanks
Pete