Garage door repair

[Clint]

Hello all As per title. The outlaws garage door is broken. To start one cable snapped leaving the door hanging to one side and jammed in the opening..this is where I squashed my finger trying to force it.
Anyway,the only way I could get it to drop square was to cut the other cable which I know was not the correct thing to do. I should have tried locking off the spring but it's done,so all tension is gone. Door is now back on the roller tracks and square but can't really be used.
I've researched replacing the cones and cables etc,tools required etc and can buy the lot Inc tools,punch and tension bars for £25 specifically for the door,it's a Henderson Merlin pre 1982.
I've watched all the YouTube I can find. The only thing I'm struggling to understand is retension of the spring which sounds like it can be dangerous!
Any experience out there please?
Cheers!

 

[Rodcx500z]

I've watched all the YouTube I can find. The only thing I'm struggling to understand is retension of the spring which sounds like it can be dangerous

Yes they are as my mate found out after being knocked cold and spent 3 days in hospital, be careful

 

[JockyBrewer]

When I last had to replace a garage door cable I was also intimidated by the spring.

I called out a pro who attached the cable to the spring mechanism, threaded it through the pulleys and then grabbed the loose end with mole grips and pulled it in to place. He made it look easy.

 

[LeeH]

Is it the type with there all long pre tensioned spring? These store a lot of energy, accidents happen.

 

[Clint]

Got a spring across today top. There's no tension in it now,I think,as I cut the other cable which was still under tension.

 

[Clint]

It's a spring wrapped around a spindle which has cones on the ends the wires wrap around when the door is raised. The spindle can be locked off with some supplied pins while the spring is loosened via two grub screws and wound back with two bars.

 

[LeeH]

Yeah, fook that it it’s the size of my old mid 80’s double door.

 

[Clint]

It's not a double,still heavy though. I'm thinking even though the wires are off the spring will still be under tension as it's tensioned with it being twisted round the spindle and locked off with the screws..
I've ordered the bits but not going to touch it until I fully understand what's going on. Either that or someone else can do it! For about £26 I'm not bothered!

 

[RichardM]

Been there, done that. Life has been so much easier since we replaced ours with an electrically operated roller shutter.

 

[Sprocker]

Had exactly the same happen two weeks ago. Did all the research but chickened out and got a local garage door guy to do it. He fitted it in between jobs, took him 40 minutes (including a mug of tea and a chat) and charged me £50.
That spring holds a serious amount of tension....

 

[Agentgonzo]

I had a similar thing happen a few years ago. One side went, but I replaced it without cutting the other side, so the spring held it's tension.

If both sides had gone, I wouldn't have attempted it myself. Those springs are are incredibly powerful and one slip or the wrong tools makes for a dangerous accident. But your competency level may be above mine.

 

[old dog new tricks]

Had to do this when I moved into my house do yourself a favour replace the wires and the rollers they wear and jam.

GDS garage door spares is the company i used.

the big spring across the top is a bugger I had a spring tension tool from motorbike tools that was a big help but just go slow pull tension let it settle then pull a bit more it will go I ended up big levers and wedges but got it connected lubed up roller with ptfe spray every year or so since and all been well.

Not a pleasant job but can be done

 

[Dark Arts]

I did mine a few years back, just take your time, took a couple of adjustments to get the door to open correctly, I might have used screw drivers instead of the supplied tension bars as they didn't quite look up to the job to me. Oh and there will probable be a mark(different colour outside spring to inside)on the rod where the spring was tensioned to last time, use this a guide that your in the ball park for the correct tension.