go away spammer

Author Topic: In over my head, needs some help with small project.  (Read 2781 times)

0 Members and 1 Guest are viewing this topic.

Offline diamindTopic starter

  • Jr. Member
  • **
  • Posts: 8
  • Helpful? 0
In over my head, needs some help with small project.
« on: March 02, 2014, 10:02:19 PM »
Hi guys,

Seems like I'm in over my head.  Started off as a little idea to motorize a small ornament which would be simple enough if I knew what I was doing, although i do not!
There's a little bit more too it than I first thought, so I'm putting it out there to anyone who has the knowledge that would like to help me on this project.  I'll order n supply the parts needed then at the end judging of the success of the design etc,  I'll offer a small donation for your time.
Alternatively does anyone know of someone that offers this kind of service?
Cheers!

Offline Kohanbash

  • Supreme Robot
  • *****
  • Posts: 430
  • Helpful? 1
Re: In over my head, needs some help with small project.
« Reply #1 on: March 03, 2014, 07:47:36 AM »
Hi
What type of item are you trying to motorize?

If you are just trying to spin an item in a continuous circle you can just connect a small (slow) DC motor to a battery.
If you need to slow the motion more, or want to have speed control you can get a motor controller.

There are many types of controllers.
If you want to control it yourself you can use something like this http://www.midwestmotion.com/speedcontrols.htm
If you want to control it from a microprocessor or radio control then there are other options such as http://www.dimensionengineering.com/products/sabertooth2x25
Robots for Roboticists Blog - http://robotsforroboticists.com/

Offline diamindTopic starter

  • Jr. Member
  • **
  • Posts: 8
  • Helpful? 0
Re: In over my head, needs some help with small project.
« Reply #2 on: March 03, 2014, 08:22:28 AM »
Hey thanks for dropping by.  Yup that's exactly what I want to do, nothing too fancy, it just needs to go slow about 1 or 2rpm and be silent.  Sounded simple to me at first but I'm running into trouble getting a silent motion at an affordable price.  Someone suggested using a stepper motor altho to set one up with an simple speed controller is beyond me.  I'm not even sure if it's possible.  So thats why I came here.

Offline Kohanbash

  • Supreme Robot
  • *****
  • Posts: 430
  • Helpful? 1
Re: In over my head, needs some help with small project.
« Reply #3 on: March 03, 2014, 10:21:58 AM »
A stepper motor might be overkill for this (but it would work).

How heavy is the item you are trying to rotate?
Robots for Roboticists Blog - http://robotsforroboticists.com/

Offline diamindTopic starter

  • Jr. Member
  • **
  • Posts: 8
  • Helpful? 0
Re: In over my head, needs some help with small project.
« Reply #4 on: March 03, 2014, 10:48:13 AM »
Well by the time its finished I'd imagine the weight on the bearing will be around 15kg (30-40lbs)  kinda heavy, although it will be well balanced and sitting on the best bearings I could find, basically its like a lazy susan, with a central vertical axle and about 10 iches in diameter. 

Offline jwatte

  • Supreme Robot
  • *****
  • Posts: 1,345
  • Helpful? 82
Re: In over my head, needs some help with small project.
« Reply #5 on: March 03, 2014, 11:32:10 AM »
I think "silent" will be the biggest problem.

You could wind a number of coils around the perimeter, and use a number of permanent magnets attached under the disc (assuming it's not magnetic itself) and sequence them to make a synchronous brushless motor out of the whole thing. That'd be kind-of neat, noiseless, and hidden. And hard :-)

Anything with a gearbox is likely to make some noise. Perhaps it can be shielded with some foam or whatever, so it's good enough?

Offline diamindTopic starter

  • Jr. Member
  • **
  • Posts: 8
  • Helpful? 0
Re: In over my head, needs some help with small project.
« Reply #6 on: March 04, 2014, 09:19:49 PM »
Turning the whole piece into a brushless motor is a neat idea but too hard.  Im not sure foam will do it, will a stepper motor work or not?

Offline jwatte

  • Supreme Robot
  • *****
  • Posts: 1,345
  • Helpful? 82
Re: In over my head, needs some help with small project.
« Reply #7 on: March 04, 2014, 09:56:52 PM »
A stepper motor will likely work -- but it will likely make at least a small amount of noise. Think "printer feeding paper" kind of whir.

Offline diamindTopic starter

  • Jr. Member
  • **
  • Posts: 8
  • Helpful? 0
Re: In over my head, needs some help with small project.
« Reply #8 on: March 05, 2014, 12:51:48 AM »
I can deal with a small amount of noise, a stepper motor will be alot quiter then a gearbox and motor won't it? 

Offline jwatte

  • Supreme Robot
  • *****
  • Posts: 1,345
  • Helpful? 82
Re: In over my head, needs some help with small project.
« Reply #9 on: March 05, 2014, 02:05:39 PM »
Yes, a stepper motor is quieter than a motor with gears in almost all cases.
You can still get gearing if you need to, by using a rubber/plastic timing belt.
You will probably need this because it reduces the size of motor needed, and it allows you to move the table slower while keeping steps continuous rather than discrete.

Offline bdeuell

  • Robot Overlord
  • ****
  • Posts: 189
  • Helpful? 15
Re: In over my head, needs some help with small project.
« Reply #10 on: March 05, 2014, 03:53:45 PM »
You could use smooth belts instead of timing belts to eliminate the noise of the teeth meshing, although at slow speeds this noise would negligible.

What about using a brushless motor with a smooth belt drive? The stepper motor will probably be quieter tho if you keep the speed down ... they can "whine" a little at higher step rates.

Offline Kohanbash

  • Supreme Robot
  • *****
  • Posts: 430
  • Helpful? 1
Re: In over my head, needs some help with small project.
« Reply #11 on: March 05, 2014, 08:31:26 PM »
Hi
What is more important; simplicity of setting this up or being as quite as possible?

A Brushed DC motor will be a little louder (but can still be pretty quite) while a Brushless or Stepper motor will be a little harder to control but quieter.
Robots for Roboticists Blog - http://robotsforroboticists.com/

Offline gerard

  • Full Member
  • ***
  • Posts: 54
  • Helpful? 2
Re: In over my head, needs some help with small project.
« Reply #12 on: March 06, 2014, 09:10:52 AM »
the easiest way to do this is to use a slow, silent ac motor
http://www.ebay.com/bhp/1-rpm-motor-synchron
something like this you can connect directly to a wall plug with no hassle of motor controllers, batteries, or other stuff
it is very silent, and used for applications that need very slow speed
you can find several types, at any slow rpm you could need
they are also pretty strong so all you would need to do is drill a small hole in the shaft to hang your ornament from

hope this helps :)

PS i used one of these kinds of motors before to make a turning stand for a watch (to keep it actively charged) and it was extremely silent

Offline diamindTopic starter

  • Jr. Member
  • **
  • Posts: 8
  • Helpful? 0
Re: In over my head, needs some help with small project.
« Reply #13 on: March 07, 2014, 01:26:41 AM »
Hey thanks for joining in and helping everyone :)
So stepper motors are very cool so I'd like to try and set one up if I end up going down that path.
Although I think garard may have nailed it with his synchron motor suggestion.  I might order one and check it out.  If that fails I will be looking at getting one of these. 

http://www.arcus-technology.com/products/6.html

Does anyone know what size I'd need?

and set up it like this.

Low Cost Stepper Motor plus Driver with analog speed control and direction change

Thanks again :)








Offline diamindTopic starter

  • Jr. Member
  • **
  • Posts: 8
  • Helpful? 0
Re: In over my head, needs some help with small project.
« Reply #14 on: March 07, 2014, 01:47:08 AM »
Just an update ive just ordered 3 different AC SYNCHRONOUS MOTORs one at 1rpm, 5rpm and 10rpm
I will let everyone know how they go.  :D

Offline diamindTopic starter

  • Jr. Member
  • **
  • Posts: 8
  • Helpful? 0
Re: In over my head, needs some help with small project.
« Reply #15 on: March 07, 2014, 05:10:08 PM »
Any one know of where to buy quality v-pulleys and belts?

Offline jwatte

  • Supreme Robot
  • *****
  • Posts: 1,345
  • Helpful? 82
Re: In over my head, needs some help with small project.
« Reply #16 on: March 07, 2014, 07:32:13 PM »
SDP/SI or McMaster (think the former are cheaper)

Offline bdeuell

  • Robot Overlord
  • ****
  • Posts: 189
  • Helpful? 15
Re: In over my head, needs some help with small project.
« Reply #17 on: March 07, 2014, 08:40:29 PM »
Tractor Supply and the like can be a good source as well for standard v-belt pulleys as well

 


Get Your Ad Here