View Full Version : How do I replace the Quill Clock Spring on my Bridgeport?

08-07-2005, 12:46 PM
The clock spring on the quill of my Bridgeport vertical mill decided to break so I took the old spring out. The hole on the outside of the spring couldn't take it any more and split so I cut it off and drilled a new hole hoping I could reuse it. It's a understatement to say getting the old spring back in is difficult.

Anyone have any tricks or suggestions on how to get it back in? Or do I need to buy a new one because they come more compressed or banded so it goes in easier?



08-07-2005, 05:49 PM
As I recall, the spring sits in a top hat looking cup. If so, we use a spanner wrench to tighten up the cup, in turn it tightens the spring. The trick as I remember is that one of the spanner pins goes in the screw hole of the cup only and the other locates on the outside of the cup rim. This allows the second screw hole to be open for a screw to keep it in place.

Let me know if I'm close or if you have a different setup.

[This message has been edited by rockrat (edited 08-07-2005).]

08-07-2005, 08:40 PM
rockrat, your description correctly tells how to tighten the spring and/or adjust the tension.

My problem is getting the clock spring in the "top hat looking cup" so I can reassemble and adjust it.

08-07-2005, 09:53 PM
Oh.... Well, let's see. I think that we have a little doo-dad at work for doing this. I can't remember what it looks like but I do remember seeing something in the quill parts box. The last time one was replaced, I think the fellow wound it by hand. Kinda just wound it back into the cap.

I'll look around tomorrow for the stuff and see what I can dig up. Maybe by then, someone will have a good idea for you as well.

08-07-2005, 10:10 PM
I just went through this. I used a hose clamp to compress the spring enough to get it into the housing. Worked fine.

08-07-2005, 10:27 PM
Is there anyplace that you can BUY clock springs?

I could wind my own, but for the most part...I'd like to buy them off the shelf when I need one.


08-07-2005, 10:30 PM
x39, using a hose clamp sounds like a great idea. I'm going to give it a try. Thanks.

08-07-2005, 11:38 PM
There is a company advertised in the Home Shop Machinist that sells Bridgeport parts. I havn't gone to the sight yet myself but I I need to.

Ian B
08-08-2005, 02:24 AM

Hose clamps work fine - and so does a nice heavy nylon cable tie. Just keep tightening it as you wind the spring in, and (being nylon) you can then smoothly slip the spring into the housing.

At this point, it's traditional to congratulate yourself on a job well done, followed a few milliseconds later by the spring outsmarting you, escaping from the cup and exiting at high speed out of the workshop...

Good luck,


08-08-2005, 12:03 PM
Ah, I see Ian has experience with this.

I went thru that exercise with a drill press. ... it went just like Ian said.

08-16-2005, 08:23 PM
Just thought I'd report back that I used a hose clamp and it worked fine.

Thanks everyone for your suggestions.