Update: This broke a week later. The cartridge won’t hold tension. I suggest rethreading to mod it into a corded blind. There are more than a few tutorials on how to do that out on the interwebs already.
My advice: just don’t. That’s right. I did it. I fixed my Home Depot Cordless Blinds, and I saved $45 doing so, but I wouldn’t recommend doing it again. I got so frustrated and it took so long that I forgot to take instructional pictures. And I love to take that kind of stuff. If the blinds no longer retract at all, it’s because all three cords have been severed. And if the fact that it happens all the time hasn’t lead you to seek alternative blinds, you might be able to repair them, but I wouldn’t recommend it.
If you’re still determined to do so, you need to:
- Pull the blind from the window completely.
- Pull out the cassette with springs and spools.
- Wind on three new cables onto the spools.
- Thread them back through all the other pulleys, obstacles, and slats.
- Replace them in the window.
Pulling the blinds from the window when they won’t retract is a pain in your arse. You’ll probably need a helper and a flat-head screwdriver to pry them loose from the bracket. The slats, which are no longer retained by means of a central cord, will try to fall out everywhere. Be careful, our use this opportunity to throw them away completely. You can still do that.
Obtaining cord is a pain. You should grab the 1-2mm kind, but it only comes in 100 yard spools from Amazon. Pull the cassette with razor sharp springs and a baffling spool-and-gear mechanism from underneath the tilt cams by unseating the cams along the whole length of the blinds. Remove the retaining clips (don’t lose them!). Clean out the busted cord from the slats, blind body, and all pulleys. Examine the cassette, and reseat the spring if it’s come loose. Which it will if you play with the mechanism for more than two seconds trying to understand how it works.
The cassette winding was the part that broke me. Play with the spools and you’ll see there are 4 in total. They counter-rotate. Without any tension on the spools, the spring is fully retracted on one spool and hooks into a cleat on the other. Play with the two thread spools, and you’ll find a slot where you can thread your cord. You’re ready to wind.
Measure out two cords, one at least 18ft long, one 9ft. Make a knot in the center of the long one and a figure 8 on a bight on the short one. With no tension on the spools, thread the center knot into the spool slot of the outside spool, and slip the bight into the slot of the inside spool. This was the biggest pain: Wind the cords around the spools, keeping your 3 dainty cords consistently on the same side of the spool, around spools within the cassette. I did this by using a blunt tapestry needle and a long and sharp upholstery needle. Avoid tangles, twists, and misthreading. You’ll know your winding properly when you pull both cables and the they both come off at the same rate. Then they should retract neatly as you let go. I have not tried this, you might be able to thread one side, pull it out, then just slip the other side on and wind it back as you retract the other. Leave enough leader cord out the run it from the cassette, through the body of the blinds, and down through every slat. More is always better. You can trim excess once you’re done. This would have been better with pictures. When it breaks again, I’ll add some.
Once you have wound the spools, thread the remaining cord onto the tiny pulleys in the cassette. They should all end up on the same side, the front of the main body where the tilt mechanism comes out to attach to the wand. Then pass them through the gaps in the cam supports in the main body, around the wide pulleys and back across the metal corner posts and down the pulleys which lead down to the slats. Thread each of the three cables through every slat and down through the main bottom body. Tie off the cord with a big knot, a button, or some other means of making sure it doesn’t just pull out and unthread all your hard work. Learn from me! With each cable pulled taught and knotted, you’re ready to test.
Even if you do everything right, your test could end in disaster and you might need to start over. Don’t! Just give up! Even if you do it right, it could end up tangled in a month. It could wear out just as fast. Because this design is heinous, prone to failure, and predispositioned to these kinds of shenanigans. Turn back now!
Thought I haven’t done it myself, I would recommend the truly frustrated and also thrifty find a tutorial on how to add cords back to your cordless blinds by forgoing the silly mechanism of the cassette and spring and just attaching a cleat to the wall to hold the tension. If you can make sure the strangulation risks are minimal in your house, it’s a way to fix them without replacing the blinds themselves.
