I want to attach a spur gear with a bore diameter of 6mm onto the shaft of this motor
(6mm diameter shaft). How would I go about doing this? From what I see, the shaft is smooth so is my only option to find a gear with a set screw? Or is it sufficient to attach a gear with no set screw and simply rely on the friction of the bore? The torques will be low.
Are there any websites that one would recommend for finding gears like this? I'm finding it impossible to find gears with a module of 1.0, bore diam. of 6mm, 12 teeth, and a thickness of less than 20mm to fit onto the shaft.
Pndlm:
I want to attach a spur gear with a bore diameter of 6mm onto the shaft of this motor
(6mm diameter shaft). How would I go about doing this? From what I see, the shaft is smooth so is my only option to find a gear with a set screw? Or is it sufficient to attach a gear with no set screw and simply rely on the friction of the bore? The torques will be low.
Are there any websites that one would recommend for finding gears like this? I'm finding it impossible to find gears with a module of 1.0, bore diam. of 6mm, 12 teeth, and a thickness of less than 20mm to fit onto the shaft.
Any help would be greatly appreciated.
The answer depends entirely on the torque the gear is subject to and the material the gear is made of.
But there are several things to consider. A set screw actually needs 2 set screws 90 degrees apart. And the motor shaft needs to have flats where the set screws can be seated because the set screws must deform the metal in order to do their work. And there are set screws with different bottom configurations.
A permanent attachment of a gear to your motor shaft is to cross drill both and drive a pin into the hole so the gear and motor shaft are permanently locked together.
Hope that helps a bit. Good luck and measure often, cut once.
If the gear is metal, there might be a possibility to soft solder the gear on to the shaft, but you would have to be quick getting it done. Something like JBWeld might also be an option.
It may also make the gear permanent unless you are prepared to break something.
For a low torque application I would start with friction and if that didn't work I would try some Evo Stik impact adhesive which has the advantage that it grips well but can be removed. Superglue would be my 3rd option.
"I don't think any locktight will hold a gear for this motor"
As small as the motor is, the OP may not have many options. If the gear fit is tight, I'd try red Loctite before cutting. grinding, and drilling. As the shaft is exposed on both sides, a press fit gear might work if the OP can get one.
4Nm is a lot of torque on a 6mm shaft, grub screw and flat is definitely the easiest way to do this that can actually hold up under load, or cut small keyways if you have the machine shop needed. One other option is a roll-pin.
I have been relying on the OP's statement in his Original Post "The torques will be low".
I have also been assuming that the OP is talking about a plastic gear as it seems to me unlikely s/he is contemplating press-fitting a metal gear as that is not a trivial procedure.