How to tap a plate to match motor mounting threads

mariner3302

Registered
Registered
Joined
Feb 27, 2015
Messages
105
Is there a way to tap a 1/2" plate so that when the bolt is threaded through the plate, it will continue into the motor threads?
I have to mount a motor to a plate to fit it to my mill with 4 bolts.
Not sure if I am using the correct terminology. I must not because I am having no luck searching..
 
I'm just spit balling here, I think you would have to clamp the motor to the plate, and run the tap through the motor into the plate to stay synchronized, if that makes sense. the engagement between plates might cause interference/separation. What J was/is thinking crossed my mind also.
 
The motor bolt holes are closed. I hadn't thought about clamping force which is valid. I'm thinking about rotational torque. The motor plate will be bolted to the mill.
Mostly, I am curious and would like to learn new things.
 
If your ending thread on the plate is clocked differently than on the motor, the bolt will push away from the motor until the bolt engages the first thread on the motor. I can see it in my head, hope the explanation makes sense.
Edit
The plate will push away from the motor.....
 
Last edited:
Is there a reason that you want the plate to be tapped? Normal procedure would be to have a clearance hole in the plate so the bolt goes through the plate and threads into the motor. then the bolt head will clamp the plate tight to the motor as it is tightened.
 
The motor bolt holes are closed. I hadn't thought about clamping force which is valid. I'm thinking about rotational torque. The motor plate will be bolted to the mill.
Mostly, I am curious and would like to learn new things.
The friction created by the clamping force (assuming the bolts are large enough) should be more than sufficient to overcome the torque of the motor. NEMA mount motors are designed to be mounted with countersunk bolts /through holes to a plate, so as long as the bolts are torqued I would expect it to have no problem here.

In your case, it looks like you want to countersink the holes in the plate that go into the motor, then can use normal bolts into the mill itself, right?
 
There should be no problem treading the plate. Then a bolt can be threaded through the plate and then into the motor threads. As was stated above there would be no practical way to apply any clamping force between the motor and the plate. unless you can turn the plate with the bolt already through it (only possible for one bolt through the plate. Think about an all-thread rod with two nuts and you can only turn the all-thread. You can turn the all-thread as it engages a nut and a second nut but unless you turn a nut, you can not change the spacing between the two nuts.
 
It will not be square also, I was trying to explain.
 
Back
Top