How to retension a Velux blackout blind GGL4?

Assuming you are right handed.....

1. Hold the roller in your left hand (it may be an idea to unwind as much fabric as possible from the blind to avoid creasing the fabric)

2. With the tool supplied...or just using the black end bracket ... wind the spring up with your right hand by turning it the set number of rotations based on the instructions below...until it wont turn any more.. (keep a tight hold of this tool once the spring is wound up)

3. Now the critical bit !
While keeping a tight grip of the tool in your right hand, rock the roller back and forth as fast as possible to lock the tension in place. The motion required is similar to how you would "rev" a motorbike. It can sometimes take a full 1-2 minutes of being rocked back and forth for the tension to lock in place so some perseverance may be required. You will know it has worked when the tool in your right hand is no longer trying to unwind itself.

Refit the blind into the black end pieces and replace into the window frame.

Bish100
April 2018

I would like to thank this thread for giving me enough of a clue to enable me to retension the spring mechanism at the heart of my velux blackout blind.
A combination of descriptions from Duncan B & John S and a youtube video called 'tensioning a velux blind' by Kit Davidson was enough to understand the process.
The main issue I had was removing the blind, which appeared to be stuck-on. I had lost the installation instructions and the passage of 15 years hadn't helped.
As a after-thought, I do find it strange that the spring comes loose in the first place, but glad that the re-tensioning is possible without too much effort.

miagdude
May 2017

Yup, as mentioned below. Once you have removed the roller tube and blind, withdraw the tensioner assembly from the tube by pulling on the metal spigot with a pliers. If the spring has become detached, re-engage the spring on the threaded end, then reassemble, engaging the key inside the tube with the cut-outs on the tensioner.
Refit to the frame, giving the rolled up blind some 20 clockwise turns to tension.

Keith
September 2016

John S is absolutely right. I've just repaired my Velux blind (no tension in spring) by following his instructions. To go into a little more detail, if you've got the blind tube out, try turning the rectangular bit of metail clockwise with a pair of pliers - if it doesn't tension up then the spring has come unscrewed inside. If, using the pliers, you pull on the rectangular bit of metal as though you're trying to pull it out of the roll, the whole mechanism will slide out - you may have to jiggle it to get the final end piece out. Once it's out, simply wind the spring round the black plastic screw thread like you're tightening a screw. Once you've done this, you can reinsert it, noting the dog-tooth gap in the black plastic end which needs to be matched to the insert in the blind tube. Before re-installing, you need to tension the spring - I didn't use a special tool, I simply rolled up the blind fully, then let it out by about 2" then used the corresponding black plastic end fitting to wind up the tension (clockwise) - maybe 20 turns. Note that the rectangular bit of metal is slightly concave so only fits one way into the black plastic. Then fit it all back together!

Duncan B
April 2016

Velux will send you instructions on how to retension using a pair of long nosed pliers.

Fraser
January 2016

Didn't notice that a tool was available till too late.
I made (one saw cut) a 'tool' from an old radiator wall bracket (the notch the radiator sits in is perfect) You just fit the notch around the spigot at the spring end. Give it about ten clockwise turns and then carefully holding it to prevent it spinning off, place the pin end into its hole then carefully push your spigot into the plastic retainer - then pull out the tool - perfect.

College House B&B
August 2014

i have a small blind company in bucks.as i supply and fit velux blinds[21years] it is posible to retention the spring if it is not broken,just unwound.velux have a tool which you can purchase direct.this will work an all velux sprung blinds

ray the perfect blinds
July 2014

The main spring is inserted in the tube on which the blind is rolled upon. First check to see if you can retension spring by turning spigot in a clockwise direction you can do this with pliers and if after many turns the spring does not offer any resistance you will need to take the spigot end off and repair the spring it sometimes unwinds and needs screwing on to the thread on the opposite end to the spigot. After this insert spring assembly back into tube and retension spring. It s a bit fiddled to reassemble because you have to prevent the spring from losing tension.

John S
May 2014

how do i re install my velux blind

samantha
March 2014