Nema 17 and 4cm fan

Hi All,

I have a stepper motor (with dimension identical to Nema 17 stepper motor), and I want to mount a 4cm fan on it. However, when I tried to do that, I found that the screw holes of the stepper motor are 31mm apart, while that of the 4cm fan are 32mm apart. I'm really deeply shocked by the situation.

Is there any 4cm fan on the market with 31mm apart screw holes? By the way, who is responsible to the decisions of stepper motor dimensions and fan dimensions?

( :frowning: It is really really discouraging. )

Yours faithfully,
Gary

Well nema 17 means 1.7 inch that's 4.3cm, no wonder the distance between holes doesn't match.

Are you saying... there is no fan on the market with its screw holes 31mm apart?

holes of the stepper motor are 31mm apart, while that of the 4cm fan are 32mm apart

Use a smaller diameter screw.

LarryD:
Use a smaller diameter screw.

Arr.. off by 1mm. It's way too big for me to do anything even in a dirty way.

I found OCD diminishes after 55. :wink:

LarryD:
I found OCD diminishes after 55. :wink:

You don't even know what I'm doing. How do you know precision is important or not to my application?
If you are eager to make some comments, you can ask what I'm doing first.
If you are too busy for that, you can simply save your time all together.
Why are you doing something in between?

You don't even know what I'm doing. How do you know precision is important or not to my application?
If you are eager to make some comments, you can ask what I'm doing first.
If you are too busy for that, you can simply save your time all together.
Why are you doing something in between?

Actually my OCD comment was for me not you!

What are you trying to do (I foolishly thought all you were trying to do was cool the motor and nothing was critical, sorry)?

Edit: Can you use a round file to enlarge the holes?

semicolo:
Well nema 17 means 1.7 inch that's 4.3cm, no wonder the distance between holes doesn't match.

2 digit NEMA numbers refer to face mounting plate sizes in tenths of an inch I believe,
3-digit NEMA numbers are different (I think its side-mount plate to axis distance or something
like that)

Mounting holes are probably not covered by the NEMA classification since it covered cylindrical
and square motors...