Help. Info on Tempering Brass Click Spring?

[P Gorman]

Working up a Gilbert Small O.G. 30 Hr. The Time side Click Spring (Brass) is fatigue cracked just beyond it's attachment point to the Great Wheel spoke.

It might be possible to Braze or Silver Solder the hairline crack but I would be concerned about creating a stress riser at that point. Experience/ Opinions?

My solution is to fabricate a replacement spring from sheet brass. Which brings up the question. Were the original Brass Click Springs Tempered? And, If so, how? :confused:

Paul

[P Gorman]

Working up a Gilbert Small O.G. 30 Hr. The Time side Click Spring (Brass) is fatigue cracked just beyond it's attachment point to the Great Wheel spoke.

It might be possible to Braze or Silver Solder the hairline crack but I would be concerned about creating a stress riser at that point. Experience/ Opinions?

My solution is to fabricate a replacement spring from sheet brass. Which brings up the question. Were the original Brass Click Springs Tempered? And, If so, how? :confused:

Paul

[bil2054]

Paul the only way to harden brass is by working it, i.e., hammering, rolling, etc. The term tempering applies primarily to steel or iron, and refers to the adjustment of the degree of hardness after full hardening, (fully hardened steel is very hard to cut, and also brittle. "Drawing", or tempering, re-aligns the crystalline molecular structure, so it is more tough than brittle.)
I agree that soldering might not work, but more because you would be annealing the piece than because of stress concerns.
You could take a piece of sheet brass and "work" it with a hammer and anvil, and then cut and file it to shape.

Bill Miller
NAWCC Member #157710
Bill's web page (http://bil2054.freeservers.com)

[LaBounty]

Hi Paul-

Brass doesn't respond to heat the way steel does. Once you heat it to a certain point it becomes soft (annealed). The only way you can harden it again is to work harden it (hammer it out). No method of heat treatment will harden brass again. The brass is manufactured hard and if you want a hard brass click spring for your movement you will have to make a new one out of hard brass. Sorry.

The original click springs were made out of brass that was rolled in a press (work hardened) and were therefore pretty hard. I believe they would have been used in their hard form and not tempered as this would have made them soft (and useless as a click spring). Old brass has a tendency to become brittle and fracture, possibly due to repeated contact with ammonia, and isn't usually repairable when used as springs.

Good luck with it!

David.

[P Gorman]

Bill, David,

Thanks for the quick replies. I will be making a replacement today.

Paul

[Dick Feldman]

Before this thread works it's way to the bottom of the pile, I think it is time to comment. I probably will be shot in the knees for my views, but here goes.
Brass is not a suitable material in my book for click return springs. They are prone to failure because the brass fatiques with time, allowing the click to disengage, usually while the clock is being wound. The rapid spinning of the key will take hide off of the hand winding the clock. This action will sometimes take a few teeth off of the first wheel and sometimes the second wheel pinion. It is common for the second wheel arbor to be bent as well. To me, that is a lot at stake to maintain originality with brass click springs. A good number of the clocks I see that are equipped with brass click springs already have the points rounded off of the clicks. That is caused from the click not catching a tooth on the ratchet and skipping to the next.
My normal proceedure is to replace the clicks and use spring steel return springs.
In some instances, I have even added a second click (with spring steel return spring) on each first wheel. Chances of failure with two clicks are almost nil.
I would welcome your comments.
Dick Feldman
Bertoud,Colorado

[gre406]

Dick..I agree

Any repair I have ever made has been with "spring steel"...

Why?? Because it works!!!!!!

Geo
NAWCC#78594

[LaBounty]

I'm not sure I'd go as far to say that the brass click spring is always to blame for rounded ratchet teeth and sore fingers. It is far more likely improper winding technique is the culprit.

The areas I address when restoring a clock are:

Key...does it fit properly or is it too large?
Wind Arbors...are they rounded off because of a key that is too big?
Click...is the tip worn and with a burr that will cause it to stick?
Click Rivet...is it loose and ready to fail?
Click Spring...is it improperly shaped, not enough tension, or forcing the click away from the wheel?
Ratchet Wheel...is it damaged and in need of reshaping the teeth because of any of the above?

It has been my experience that spring steel will fail far more quickly as a click spring in clocks where the click was brass and has a lot of travel. The steel becomes work hardened and fractures. That is why English longcases, banjos, and others where the click is attached to the rim of the wheel, will have a shaped brass click spring. The brass will withstand the repeated motion without fracturing. And it was less expensive.

As you can tell, I'm more in the "keep it like original" camp but have enough of an open mind to not aim at the knees when an opinion is expressed! Each person will have to decide what is right for them, their customer, and the clock.

David.

[Tom Chaudoir]

A small note. I'm a firm believer that the points of contact between the click and it's wheel should be lubricated. My habit is to use the same high pressure oil on the click rivets, click wheel teeth, click wheel bearing surface, spring/click juncture, and winding arbor pivots. Most of the time the second wheel pivots get the same oil. The rest gets synthetic clock oil.

Names of lubricants have been withheld to preserve the peace :smile:

Regards,

Tom Chaudoir
Milwaukee, WI
America
150429

[lpbp]

From what I have seen on clocks coming in for repair that have been worked on in last few years by other repair-people, is the need for attention to click springs and clicks. I find loose rivets, burrs on clicks, wear on clicks, weak and non-adjusted springs. This is an area I cannot stress the importance of repair enough, as was stated earlier failure in this area can have serious consequences.

Larry Pearson, FNAWCC #35863 L138
candiate for Director