Expansion Spring End Fittings?

I'm looking for the correct name and any suppliers of off the shelf expansion spring end fittings.

The type I'm looking for are made of strips of steel about half as wide as the inside diameter of the spring and are "U" shaped with bent out formed ends which slip between the coils of the spring on opposite sides, a few turns from its end.

A hole in the center of the bottom of the "U" accepts a bolt or stud to connect the spring end to whatever it's pulling on.

The springs I'd use them on are about 1-1/2" diameter.

I think that kind of attachment would survive longer than the classical loop end made by bending the last turn and a half of the spring so it's at right angles to the spring axis. That type of end, not usuprisingly, has a propensity for failing at the bend point.

If you haven't guessed by now I'm talking about garage door tension springs. Ours always seem to fail at that end loop bend point and I'm getting pissed at having to repair or replace one of the four springs on our two garage doors once every couple of years, it's a dumb ass chore to do, especially since I have to remove and replace the safety cables I ran through the springs the first time I saw what an unrestrained snapped off spring failure did to the wall it slammed into.

I just spent an unexiting hour fixing one tonight by torching and bending a new end loop on it. I'm thinking the springs would last a heck of a lot longer if they were fitted with the kind of attachments I described above.

Thanks guys,

Jeff

Reply to
Jeff Wisnia
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Ummm ... heating it up? You know that you ruin any spring by making it (red) hot. If you bend the end of a expansion spring (you do that cold), you have to put the spring into the ofen for some hours at about 200..250 °C to relief the stress in the bend.

Nick

Reply to
Nick Müller

There's got to be something wrong with the way the original springs were installed. My (5) garage doors are over 40 years old and the springs have never been replaced or repaired. They work fine. As stated before, heating the ends or shortening them up will really screw things up. Bugs

Reply to
Bugs

Wouldn't suprise me if they took more care making those springs 40 years ago in the USA then they have in recent years where G-d knows where they come from.

I have trouble thinking there could be anything wrong with the installation. The springs are the proper rated strength for the measured weight of the door and they just get stretched and released between a stationary support and the cable pulley yoke. What could be simpler than that other than never closing the garage door?

And, if spring breakage on those kind of door springs wasn't a fairly regular happening, they wouldn't bother selling safety cable sets (even at Sears) and the building codes in many areas wouldn't require them.

As far as screwing up the springs go, I don't think the door will really notice that one spring is a turn and a half shorter than the other, and I only apply the torch to the place where I make the end loop bend, while the two adjacent coil is sprung away from it by a wedge.

Admittedly it's a small sample of four or five spring breaks in the last dozen years, but every one which broke did so right at the end loop bend, and the new loops I bent never broke, perhaps because my radiuses were somewhat more generous than the original ones which were close to right angle bends.

According to the scribbled note I left on the inside of the door on which I had to fix a spring last night, I replaced both the springs on it with brand new ones in December 2000, so it took 5 years for the next break to happen.

Jeff (Not *really* taking himself too seriously about this 'yknow.)

Reply to
Jeff Wisnia

measured

The reason for the safety cables isn't just spring breakage but breakage of the door cables and the attachment points themselves.

radiuses

Reply to
Steve W.

Ouch! I was so obcessed with those damn loops stapping of at those sharp stress inducing bends, that I forgot about the rest of the components under tension. Prolly because I never personally experienced any of

*them* breaking in a house we've lived in. it's always been those damn end loops....those damn end loops...those damn.....(ad nauseum.)

That demostrates once again that two (or more) heads are better than one.

Jeff

Reply to
Jeff Wisnia

I've had the end connections pull out of a door one and had a couple of failures at the pulley. Worst one was at the fire station. We have now gone to rotary spring assist because of it. That one almost caused a BIG problem because the cable failed when they were opening the door en-route to a fire call. Cable just missed one FFs head but hit the fender on the rig hard enough to crease it.

Reply to
Steve W.

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