How I replaced deadly garage door torsion springs (2002) • Hacker News Board

Re: How I replaced deadly garage door torsion springs (2002)

#311

Post by pengaru » Tue, Mar 19, 2024, 3:14 PM UTC

lobsterthief wrote: post #293

arh68 wrote: post #75

> but the risk is comparable to doing your own car repairs "Comparable" in that it's way, way greater , sure. Unless we're talking dangerous car repairs, like using a spring compressor to disassemble a strut &c. Or using harbor freight jack stands.. When my spring broke, I thought someone crashed their car into my house. It's an incredible amount of energy. Garage door springs are up there with lathes & table saws, i…

Honestly, Harbor Freight jackstands are just as safe as the others (sans the recalled ones from 2020ish). Regardless of brand, you want to employ a backup safety system—like removing some wheels and shoving them under there.

I used to do a lot of at home automotive work, and in the early days relied on jack stands since it's what was sold for the purpose and being a kid I didn't know better yet.

But after several years and a few close calls with cars unexpectedly shifting on the stands while applying work forces from below, I started using ramps and/or cribbing made of plain stacked dimensional lumber like 2x8s, and just scrap blocks of wood in general I'd taken from heavy duty pallets.

Jack stands just plain suck, it doesn't matter who made them. They're rigid at the vehicle interface (usually cast steel/iron) and generally only make very little points of contact over their cast in, small area profile - not even considering the tipping hazard when extended.

Solid chunks of wood piled up like cribbing is far more safe, and in my experience, free. And as an added bonus now you have chunks of greasy wood on hand for whacking things on/with less-destructively...

Re: How I replaced deadly garage door torsion springs (2002)

#312

Post by 83 » Tue, Mar 19, 2024, 3:18 PM UTC

amluto wrote: post #126

levocardia wrote: post #5

I had a teacher in high school who was blinded (I think only in one eye) trying to do this repair. You could not pay me enough money to do this repair. >This work is risky, but the risk is comparable to doing your own car repairs, or climbing on the roof of your house to clean your gutters. Notably, "unintentional fall" is the #1 cause of emergency department visits for adults [1], which is why I'd hire a professiona…

I don’t understand why it’s even considered safe to have one of these springs in one’s garage without a solid shield of some sort. While the energy involved is small on the scale of energy storage devices ( Which brings to mind some rather different designs. A rather small motor with a lot of mechanical advantage can easily open a close a garage door, and if a DC or low voltage AC motor is used, it could do so quite…

The spring counteracts the weight of the door. In the event of motor or electricity failure a well adjusted spring/door will be easy to manually open. A direct drive/worm gear would require an uncoupling mechanism and the ability to lift the full weight of the garage door overhead to get out.

Attention is required when changing these, but they really don't pose that great of a risk. I've been present when one broke, and I've changed them myself. As noted by others - the spring stays contained by the metal shaft. They really aren't worth substituting with something that has more drawbacks when a spring's lifespan is on the order of decades.

Re: How I replaced deadly garage door torsion springs (2002)

#313

Post by tmaly » Tue, Mar 19, 2024, 3:26 PM UTC

Knufferlbert wrote: post #49

tmaly wrote: post #7

I have had to replace mine before. I was sitting in the family room. Big slam sound. I go out and check the garage and one of the springs had broke. It is really not a big deal to switch them out.

That is a very weird take to me. That big slam presumably is the spring breaking, a lot of energy released at once in a rather uncontrolled fashion. The same energy will be released if you make a mistake installing it or the spring is faulty for whatever reason while you are standing right next to it. My take away is that it's to dangerous to do.

If you take the weight off the spring so it is limp, and you secure the door, this removes the danger.

Re: How I replaced deadly garage door torsion springs (2002)

#314

Post by tmaly » Tue, Mar 19, 2024, 3:27 PM UTC

ianschmitz wrote: post #22

tmaly wrote: post #7

I have had to replace mine before. I was sitting in the family room. Big slam sound. I go out and check the garage and one of the springs had broke. It is really not a big deal to switch them out.

Oof. Just because you did it yourself does not mean it wasn’t extremely dangerous, or that the average home owner should attempt it. There’s an incredible amount of energy stored in those springs when wound up

I am not talking about wound up springs. This is a simple spring you usually see in pairs, one on each side of the garage door.

Re: How I replaced deadly garage door torsion springs (2002)

#315

Post by Retric » Tue, Mar 19, 2024, 3:33 PM UTC

matt-attack wrote: post #308

Retric wrote: post #283

Earlier quoted context omitted.

Counterweights don’t need to take a straight path to the ground. The force a weight pulls on a surface is based on the tangent.

True but by adjusting the angle you still end up with a fixed weight throughout the run. A spring force changes throughout the movement of the garage door and that’s chosen to match the unusual fact that the garage door’s weight changes as it’s gets progressively rolled up onto the top rails.

A fixed weight but not angle means the force varies. Cut the cable and acceleration would therefore also vary with that angle along the track.

Springs make a lot of sense from an installation perspective and can be easily tuned to match the specific door design, but if I was working from scratch on a DIY project I would prefer to use a counterweight if there was somewhere it fit.

Re: How I replaced deadly garage door torsion springs (2002)

#316

Post by amluto » Tue, Mar 19, 2024, 3:47 PM UTC

mnw21cam wrote: post #279

amluto wrote: post #126

Earlier quoted context omitted.

I don’t understand why it’s even considered safe to have one of these springs in one’s garage without a solid shield of some sort. While the energy involved is small on the scale of energy storage devices ( Which brings to mind some rather different designs. A rather small motor with a lot of mechanical advantage can easily open a close a garage door, and if a DC or low voltage AC motor is used, it could do so quite…

I recently accidentally drained the battery on my car while I was fixing unrelated stuff on the door (and therefore had the door open for 3 hours). I bought a "jumpstarter kit" which is basically a 12000mAh LiIon battery (3.7V) and some electronics. It's just a little bigger than a large mobile phone, but you clip it to the car battery and it's capable of providing 12V at 600A to turn the starter motor for up to 5 se…

Some pedantry:

1. It’s unlikely there’s power conversion circuitry in the kit. It’s almost certainly a few cells in series.

2. I’d be surprised if it can actually produce 600A at 12V. It’ll be “12V nominal” into an open circuit, which is really more like 14V for a 4-cell Li-ion setup. But even a 600 cold cranking amp lead-acid battery only supplies 7.2V at 600A.

Re: How I replaced deadly garage door torsion springs (2002)

#317

Post by j-a-a-p » Tue, Mar 19, 2024, 6:56 PM UTC

mnw21cam wrote: post #280

j-a-a-p wrote: post #272

Earlier quoted context omitted.

I never replace the brake fluid. I do flush each caliper when changing summer and winter tyres. This means a selected offspring presses the brake twice for every tyre and the caliper has fresh fluid in it. The fluid only degrades in the caliper, no need to replace it entirely, and no need for a computer when you do it like I described it.

It depends. Brake fluid absorbs moisture, which lowers its boiling point. You don't want it boiling from brake heat when you're really trying to stop. If you live somewhere humid then the whole reservoir can slowly absorb too much moisture and make the fluid unsafe.

No need to panic. An entire generation never refreshed this fluid and vapour lock was still a rare incident. Replacing 20% of this fluid every year is more than enough.

Re: How I replaced deadly garage door torsion springs (2002)

#318

Post by Der_Einzige » Tue, Mar 19, 2024, 7:10 PM UTC

BenFranklin100 wrote: post #244

cruffle_duffle wrote: post #184

Earlier quoted context omitted.

It’s amazing and honestly kind of sad how risk averse some people are. The reason I don’t change my oil anymore is it just isn’t worth the time and hassle. The “unsafety” of such a task doesn’t even register on my things to be worried about: at all. Jack it up, remember to put on gloves(!!!!) put the fucker on stands and go. The actual scary thing is I’m pretty sure way back when I was a kid we’d just dump the oil do…

I’m baffled too. Changing oil in a car is dead simple and effectively zero risk with a proper pair of jack stands and a modicum of common sense and mechanical aptitude.

Harbor freight famously sold unreliable jackstands for awhile. There’s memes about it in the car community.

Re: How I replaced deadly garage door torsion springs (2002)

#319

Post by BenFranklin100 » Tue, Mar 19, 2024, 8:02 PM UTC

ryanjshaw wrote: post #270

BenFranklin100 wrote: post #244

Earlier quoted context omitted.

I’m baffled too. Changing oil in a car is dead simple and effectively zero risk with a proper pair of jack stands and a modicum of common sense and mechanical aptitude.

Not everyone is born with common sense. I sure wasn't. I'll find some way to do something that will leave the people with common sense scratching their heads, saying "but why wouldn't you just...".

All right, I respect that. I’m sure there are plenty of things that I might do that would leave you scratching your head too.

Re: How I replaced deadly garage door torsion springs (2002)

#320

Post by BizarroLand » Tue, Mar 19, 2024, 8:03 PM UTC

Lammy wrote: post #169

BizarroLand wrote: post #152

Earlier quoted context omitted.

300lbs of counterweights strapped to the doors would take up a good bit of space. Pulley systems would need to either be 1 to 1 or would need some space to fall below the garage floor or to be stored above garage door height. They seem far safer, longer lasting, and cheaper and easier to repair than springs, but are more expensive to install, take up more space, and probably cost more all in all compared to springs.…

That looks super cool actually, like passing the Pillars of Hercules every time I drive https://hermco.ca/wp-content/uploads/img_14.jpg

You know, that design makes a lot of sense, since the door would be mostly horizontal by the time the pulley got close to bottoming out the motor would still be able to move it.

I bet those tubes go below the foundation though and god help you if the cable breaks and you have to fish those weights out to reattach it.

Maybe there is some easily reachable latch point on top or some sort of fluid pump port that will make it easier on you?