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Mechanics and Construction => Mechanics and Construction => Topic started by: jwatte on May 19, 2014, 04:58:31 PM

Title: Good source of 6mm bore miter gears?
Post by: jwatte on May 19, 2014, 04:58:31 PM
I'd like to mount a motor with a 6 mm D shaft at a 90 degree angle (or 60-90 degrees, really.)
What's a good solution to transfer the motor power to the wheel? I have one motor per wheel, and need to move the motor out of the hub for space reasons.

I've looked at places like rushgears.com and sdp-si.com, and all the gears they have are $25 each and up -- and I need 10 of them! (It feels weird to pay more for the 90 degree joint than I paid for motor + encoder + gearbox...)

There are some plastic gears at sdp-si that are $6 each, but they are 1:2 and 1:2.5 ratio.

Or is there another choice for a 90 degree coupling than miter gears?
Title: Re: Good source of 6mm bore miter gears?
Post by: Kohanbash on May 19, 2014, 05:28:41 PM
Mcmaster has some spur gears with a 0.25" bore. The nylon ones are $2-4
http://www.mcmaster.com/#miter-gears/=s1en4y (http://www.mcmaster.com/#miter-gears/=s1en4y)

Title: Re: Good source of 6mm bore miter gears?
Post by: jwatte on May 20, 2014, 02:28:04 PM
Thanks for the suggestion. Unfortunately, that doesn't solve my problem. First, I need miter gears, not spur gears. But, McMaster also has imperial miter gears in nylon.
Adapting from 6mm to 1/4" is actually very hard, unless you have lots of axial space for a coupling, because there's not enough space for a sleeve type adapter. Just screwing them on a 6mm shaft leaves a 0.35mm difference in concentricity, which is quite significant and jams up the meshing.

Title: Re: Good source of 6mm bore miter gears?
Post by: venturemfg on May 21, 2014, 06:20:20 AM
Try out Venture Mfg Co. (http://www.venturemfgco.com/ (http://www.venturemfgco.com/))
Title: Re: Good source of 6mm bore miter gears?
Post by: jwatte on May 21, 2014, 09:29:42 AM
I would check out Venture Manufacturing, except their web site 500s :-/
Title: Re: Good source of 6mm bore miter gears?
Post by: waltr on May 21, 2014, 11:45:26 AM
Quote
Adapting from 6mm to 1/4" is actually very hard
It is easier to buy the gear with a smaller hole then open the hole to the required size.
Title: Re: Good source of 6mm bore miter gears?
Post by: jwatte on May 21, 2014, 04:23:37 PM
I found some promising injection molded gears with 6mm bore from Quality Transmission. They had exactly 8 in stock, which is what I need for four wheels, but I'll have no spares at that point...
Title: Re: Good source of 6mm bore miter gears?
Post by: jwatte on May 21, 2014, 04:28:02 PM
OK, Venture Manufacturing was a waste of time. They have one line of 90 degree gear boxes that have 20:1 gearing or worse, and that are a lot more expensive than what I was looking for. It also comes only in half-inch shaft when I was looking for 6mm. So, minus points for not actually reading the requirements, and posting a spammy link for SEO purposes, and wasting my time.