• Spring 2024 meetup in Calgary - tentative date Saturday, April 20/2024. Other regions are also discussing meet ups. If you want one in your area get going on organizing it! discussion
  • We are having email/registration problems again. Diagnosis is underway. New users sorry if you are having trouble getting registered. We are exploring different options to get registered. Contact the forum via another member or on facebook if you're stuck. Update -> we think it is fixed. Let us know if not.
  • Spring meet up in Ontario, April 6/2024. NEW LOCATION See Post #31 Discussion NEW LOCATION

Some Mods To the Belt Drive On My Mill

terry_g

Ultra Member
I made a pulley that would fit into the top of the cone pulley on the motor to give me a slower speed
160 rpm the lowest with the factory setup was 270 rpm.

Assemble these parts.
4196325920_ba1d69f7b1_c.jpg


You will have this.
4196325924_911d156a4a_c.jpg


Slide it into the cone pulley and tighten the nut.
4196325930_302b9703d1_c.jpg


A shorter belt was required.
4196325928_f53006edfb_c.jpg


There is a wide space in the speeds in the middle between 490 rpm to 950 rpm.
By running a belt directly from the motor to the spindle pulley I was able to get 660 rpm.
4206502014_97fcb7f099_c.jpg
 

John Conroy

member
Premium Member
Very nice work. What did you do to align the new motor pulley groove to the existing idler top pulley?
 

terry_g

Ultra Member
The cone pulley was bored and had a key-way all the way through.
It just slid in and the expanding shaft holds it tight.
 

RobinHood

Ultra Member
Premium Member
The motor pulley on our machines has a blind bore with keyway. Something to keep in mind here.

You could always bore all the way through and extend the key way - if there is enough material on the step pulley.
 

RobinHood

Ultra Member
Premium Member
I think @YYCHM was talking about the pulley on the typical RF30 mill. Seems there may be a difference in design.
 
Last edited:

DPittman

Ultra Member
Premium Member
I made a pulley that would fit into the top of the cone pulley on the motor to give me a slower speed
160 rpm the lowest with the factory setup was 270 rpm.

Assemble these parts.
4196325920_ba1d69f7b1_c.jpg


You will have this.
4196325924_911d156a4a_c.jpg


Slide it into the cone pulley and tighten the nut.
4196325930_302b9703d1_c.jpg


A shorter belt was required.
4196325928_f53006edfb_c.jpg


There is a wide space in the speeds in the middle between 490 rpm to 950 rpm.
By running a belt directly from the motor to the spindle pulley I was able to get 660 rpm.
4206502014_97fcb7f099_c.jpg
I'm curious...what operation did you need the slower speed for, tapping?
 

terry_g

Ultra Member
I was using a boring head with a long bar and was getting chatter because of the lack of rigidity.
 
Last edited:

DPittman

Ultra Member
Premium Member
My similar milling machine only has .350" of room in the cone pulley so not much room for a shaft but I guess the key takes the majority of the forces anyhow and a bit of epoxy or loctite would suffice to hold the pulleys together 20210403_124401.jpg
 

YYCHM

(Craig)
Premium Member
My similar milling machine only has .350" of room in the cone pulley so not much room for a shaft but I guess the key takes the majority of the forces anyhow and a bit of epoxy or loctite would suffice to hold the pulleys together

In that case I would suggest a shaft with key for alignment and torque load and securing the new pully to the adjacent pulley with machine screws.
 

Rotaxxx

Member
VERY INTERESTING!! I have the exact same mill and have the same complaints with mine as well! I wish it had a few lower speeds and this looks like a great idea! Thanks for posting it.
 
Top