Rf31 Rong Fu Round Mill Quill Spring Replacement Procedure

[JHoi]

I have had my RF31 for a while now and decided it was time to get the quill return working. I have seen some other posts where guys have added springs to the quill itself or even a custom windlass style winch system. Some were wanting to improve backlash while others mentioned lack of parts availability. Backlash is for sure an issue on these mills especially in the Z...as far as availability goes I am happy to report that I found stock in several places including Mcmaster and Enco. I ordered a replacement and for just under $40 I have a new spring and it came in a new housing as well.

The factory spring was long gone before I got the mill so I never did see it in place. The manual for my machine simply states that the quill is factory set and shouldn't require adjustment. In the case of a heavy tooling combination that won't retract it suggests that the spring cover can be loosened and then turned CLOCKWISE until the heavy tool will retract properly. I take that to mean that a clockwise rotation would be increasing the tension on the spring to help it pull up quill.

Now for the ???s. I'm looking at this thing and the housing is certainly a doppelganger for the original. The spring appears to be set up for a COUNTERCLOCKWISE windup if I'm looking at it correctly. The hole in the spring for the screw is to the left of the slot that it should rest in. The curly q part of the spring that goes through the slot in the housing also looks to be setup for a load in the counterclockwise direction.

Anybody out there had one of these apart and got it back together successfully? Did you start with the quill locked or free...up or down? Approx how many turns on the spring? Any other useful tips or tricks?

JH

 

[Bob Korves]

I am not familiar with that mill but if it is like the ones on drill presses and most mills it is very dangerous to take the spring out of the housing. You can get hurt. You may not ever be able to get it back in again, either. Somewhere a long time ago I saw a tutorial on how to do it safely but cannot remember how or where. Perhaps someone else here knows?

 

[Timr45]

JHoi,

Just replaced mine, on mine I put it on so the shaft would wrap it tighter as the quil moved down. I just used a small screw driver to get the end over the screw in the shaft and then put the housing over it, at that point the housing was covering about half the spring so put my safety classes on and cut the wire holding the spring compressed and at the same time pushed the housing over it.

To adjust the tension I just backed the screw that holds the housing on out just enough so the housing could clear the pins that secure it from rotating and twisted the housing tight and pushed it back in when lined up with the pins.

I started all this with the quil fully up.

-Tim

 

[JHoi]

I am not familiar with that mill but if it is like the ones on drill presses and most mills it is very dangerous to take the spring out of the housing. You can get hurt. You may not ever be able to get it back in again, either. Somewhere a long time ago I saw a tutorial on how to do it safely but cannot remember how or where. Perhaps someone else here knows?

Roger that...its basically a bandsaw blade wound up in there. The great thing about this one is it came already pressed into the housing, so I don't have to worry about that part.

 

[JHoi]

JHoi,

Just replaced mine, on mine I put it on so the shaft would wrap it tighter as the quil moved down. I just used a small screw driver to get the end over the screw in the shaft and then put the housing over it, at that point the housing was covering about half the spring so put my safety classes on and cut the wire holding the spring compressed and at the same time pushed the housing over it.

To adjust the tension I just backed the screw that holds the housing on out just enough so the housing could clear the pins that secure it from rotating and twisted the housing tight and pushed it back in when lined up with the pins.

I started all this with the quil fully up.

-Tim

So once you got the spring on the screw you dropped the quill and then you started cranking on the spring housing until it picked back up? Did you add any oil or grease to the spring?

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[Timr45]

I did not drop the quil, I just wound the housing so there was some tension and it wanted to spin in my hand at that point when you lower the quill it wraps the spring tighter and will retract the quil when you release the handle.

I did put a light coat of oil on the spring to keep the rust away.