Wiper Motors for Mill Quill??

[Whyemier]

A year or two ago I added a table power feed to my mill. It works great and I'm more than satisfied with the results. I have heard of machinists using wiper motors(windshield wipers) to drive the feed on their equipment. I want to add a feed to my quill (z axis) using a wiper motor and was wondering if anyone has done this to their mill (or other equipment). Wiper motors typically are 12V and run at 3 to 6 amps with 12 to 17 pounds of torque. Any pointers or words of wisdom?

Thanks ahead of time.

Whyemier

 

[Andre]

Should be fine, but they may have too much torque with the worm/spur gearbox on them. If you walk away boring a hole and forget about it, the quill hits say the bottom of the vise and crashes. If you use a motor too powerful there is a chance you may snap a gear tooth on the quill or quill pinion gear. Not good!

Most mills now have power downfeed anyhow.

 

[JimDawson]

I have my stepper set to decouple at about 50 ft lb on my quill pinion shaft. I had it actually decouple once, nothing broke. The max torque from the stepper is about 6.5 ft lb and is geared down 15:1. This is the way I did mine. http://www.hobby-machinist.com/showthread.php?t=21060&p=183002&viewfull=1#post183002

 

[kd4gij]

What mill do you have?

 

[Whyemier]

What mill do you have?

I did neglect to say, I guess I assumed everyone could read my mind:thinking:
I have the Rong Fu 30, mill drill or a clone thereof.
Not as versitile as a bridgeport or other knee mill but it suits my needs and available space. Suited my budget when I purchased it (old new) at the time.

BTW, thanks for all your input.

- - - Updated - - -

I have my stepper set to decouple at about 50 ft lb on my quill pinion shaft. I had it actually decouple once, nothing broke. The max torque from the stepper is about 6.5 ft lb and is geared down 15:1. This is the way I did mine. http://www.hobby-machinist.com/showthread.php?t=21060&p=183002&viewfull=1#post183002

Great photo summery of what you accomplished.

I did consider using a stepper motor but not 'understanding' there use and abuse I steered myself away from them. With your setup and modification were you still able to use the hand feed crank? Perhaps when I study your photos more closely I'll get my answer.

 

[JimDawson]

Great photo summery of what you accomplished.

I did consider using a stepper motor but not 'understanding' there use and abuse I steered myself away from them. With your setup and modification were you still able to use the hand feed crank? Perhaps when I study your photos more closely I'll get my answer.

Thank you.

I used a stepper because I wanted high torque and low rpm capability, as well as being easy to control. All of the original quill power feed hardware has been removed, so the hand wheel has nothing to connect to. I can disengage the gear train by shifting a lever on the left of the head, this gives me full manual operation via the standard quill lever.

 

[John Hasler]

I have my stepper set to decouple at about 50 ft lb on my quill pinion shaft. I had it actually decouple once, nothing broke. The max torque from the stepper is about 6.5 ft lb and is geared down 15:1. This is the way I did mine. http://www.hobby-machinist.com/showthread.php?t=21060&p=183002&viewfull=1#post183002

What does that work out to in downforce on the quill?

 

[JimDawson]

What does that work out to in downforce on the quill?

About 250 lbs. Before I started this project I put a bathroom scale on the table and pulled on the lever to what I thought was about the maximum down force. It was about 400 lbs. So I designed the system to provide that down force +, then I backed off from there for normal operation. This is a parameter in the stepper setup. The only time I have had it decouple, was peck drilling in stainless and a chip got under the drill tip, so it just quit drilling.