Tim Wescott tim seemywebsite.com wrote:

John Doe wrote:

....

Does the forward push on an ordinary electric motor cause
abnormal wear on the bearings? Or maybe that is
countered/supported by the magnetic part of the motor?

It is _not_ supported by the magnetics. It may, indeed, cause
objectionable wear -- that depends on whether the motor bearings
can absorb the thrust of the prop (assuming you prop it
directly).

For all but outrunner motors, you'd want a gear box anyway.

How about a "thrust bearing"?
"Handles thrust loads, also called an axial or side load, which is
a load parallel to a shaft. Facilitates smooth rotation between
surfaces like other rotary bearings, but their design supports
higher thrust loads. Choose from plain and ball bearing designs. "
--




















Any
non-planetary gear box (or belt drive) will put a side load on the motor
shaft, but its much more likely that the motor is designed for that.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" was written for you.
See details at http://www.wescottdesign.com/actfes/actfes.html


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Date: Wed, 28 Jul 2010 12:09:22 -0700
From: Tim Wescott tim seemywebsite.com
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Subject: What size propeller for a 36 V DC motor?
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