Author Topic: Roman blind keeps falling off cam/bracket  (Read 548 times)

Mrs Pingu

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Roman blind keeps falling off cam/bracket
« on: 01 November, 2021, 06:06:54 pm »
I'm hoping someone is just going to put me out of my misery and tell me these things are shite cos I'm starting to wonder if I'm being really stupid, it shouldn't be rocket science.

We've got a teeny tiny roller roman blind, must be less than 50cm wide and maybe 75 long so nothing super heavy.
It's got brackets/cams like the ones in this video https://www.curtainscurtainscurtains.co.uk/fitting-roman-blinds-hhid297.html
It sits up there ok if I don't touch it, but if I try to operate the chain to lower the blind then the cassette falls off the bracket.
To me it seems like a bloody stupid design where it has a lip at front and back of the cassette but only the front lip hooks over the cam hook and then the woosey lever on the cam is supposed to hold it in place (it doesn't).
I'm trying to not consume for the sake of it but this thing is really grinding my gears, is it just me or are these things crap?

I should add that this is all installed behind a pelmet so it's bloody hard to see what I'm doing.
Do not clench. It only makes it worse.

Re: Roman blind keeps falling off cam/bracket
« Reply #1 on: 01 November, 2021, 06:10:00 pm »
The brackets are fit for purpose, but can be sensitive to incorrect fitment. The best magic you can try is liberal silicone spray on the mechanism and moving parts. It's not clear from your description whether there is anything broken, my working assumption is that it isn't.

robgul

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Re: Roman blind keeps falling off cam/bracket
« Reply #2 on: 01 November, 2021, 08:32:33 pm »
If I'm understanding your problem - the little cam lever holding the channel into the brackets is quite a "positive fit" in the locked position and the whole thing is then firmly attached.

Mrs Pingu

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Re: Roman blind keeps falling off cam/bracket
« Reply #3 on: 01 November, 2021, 08:36:57 pm »
Having done a bit more Googling I think either:
I'm not pushing the back up enough to engage the rear lip (though I have a feeling I addressed that the last time I decided to have a fight with it), or
The swivel/lever on one of the brackets is knackered and doesn't stay put. Possibly it vibrates open with the action of the chain. I shall have another look tomorrow.
Do not clench. It only makes it worse.

Re: Roman blind keeps falling off cam/bracket
« Reply #4 on: 01 November, 2021, 10:04:41 pm »
On longer blinds the brackets certainly need to align very well in both planes, front - back but also be horizontal/same level, if not only a few clips engage properly and/or one actively blocks proper engagement, so perhaps check for alignment (twist)?
If push comes to shove fix a 1/2"+ batten (painted to suit) up first, and mount the brackets to that, that then should help alignment.

Re: Roman blind keeps falling off cam/bracket
« Reply #5 on: 01 November, 2021, 10:46:37 pm »
Sorry should have looked at the pic  (but do give it large with the silicone anyway if operating it pulls it off), and I could have read what you said. The fixings you have are common to venetian blinds, and normally there is a cam that goes front and back. If you can only see half, it is likely that one of the legs has snapped off (but actually nothing I've ever seen in real life, and I've seen a lot of blind and curtain brackets), it may just hook over the back, and the cam pushes one side forward.

The normal issues with fixing those brackets are that they are not in a straight line, or aren't level. Take it down, and the brackets, check that they each work independently. If they don't then a replacement is the easy fix. If they do, then put the blind up in place and see what isn't straight. If it is level, a few washers should do. Less than 50 wide you should only have two brackets anyway, so line won't be an issue.

robgul

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Re: Roman blind keeps falling off cam/bracket
« Reply #6 on: 02 November, 2021, 07:44:14 am »
Sorry should have looked at the pic  (but do give it large with the silicone anyway if operating it pulls it off), and I could have read what you said. The fixings you have are common to venetian blinds, and normally there is a cam that goes front and back. If you can only see half, it is likely that one of the legs has snapped off (but actually nothing I've ever seen in real life, and I've seen a lot of blind and curtain brackets), it may just hook over the back, and the cam pushes one side forward.

The normal issues with fixing those brackets are that they are not in a straight line, or aren't level. Take it down, and the brackets, check that they each work independently. If they don't then a replacement is the easy fix. If they do, then put the blind up in place and see what isn't straight. If it is level, a few washers should do. Less than 50 wide you should only have two brackets anyway, so line won't be an issue.

The other fundamentals are to work with an assistant to hold the rail - and don't over-reach (stand on a box or something!) while trying to locate the lip/cams etc.

T42

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Re: Roman blind keeps falling off cam/bracket
« Reply #7 on: 02 November, 2021, 07:50:39 am »
I get the impression that those things are, as you say, shite.  Toss it and put in a standard venetian.  The one in my office has been working perfectly for over 30 years.

Having said that, of course, the cord will snap this afternoon.
But they never got to Carcassonne.

Re: Roman blind keeps falling off cam/bracket
« Reply #8 on: 02 November, 2021, 08:12:46 am »
Now here's a thing. Back in my dim and distant past (actually >40 years - b*gger me) I was a curtain fitter. Out of curiosity, I've been having a mooch about and it appears that the tech in the design of rails has not changed one bit. As a  professional installer the go-to rail is still Kirsch (either "Pro", "standard" or deluxe ready corded) with I-beam and roller glides available too, Swish/Harrison Drape still dominate the UK domestic market with identical rails to years ago, and a variety of custom nylon runners in aluminium sections available for architects to fulfil their wet dreams. Nothing significant has changed, either because the curtain rail has reached the epitome of design, or nobody can be bothered.

Feanor

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Re: Roman blind keeps falling off cam/bracket
« Reply #9 on: 02 November, 2021, 08:59:09 am »
I have a bunch of these fittings in the flat in Edinburgh, and I have some observations...

We have mostly roller blinds, but one set of wrinkly-tights design, all sourced from JL just along the road in Embra.
The difference between them is this:

The roller blinds have u-shaped brackets at either end to accept the ends of the roller, and one or more of the butterfly twist-lock brackets mid-span to prevent the roller bowing downwards.
The vertical load is almost entirely taken by the more substantial u-brackets at the ends of the roller, and this is where the hauling of the cord is applied. There is almost no load on the mid-span twist-lock brackets.  These are absolutely rock-solid.

The wrinkly-tights blind has no roller, and is entirely supported by twist-lock brackets, and is prone to getting pulled down, particularly if you haul on the cord at an angle outwards rather than vertically down.

I investigated it, and came to the following conclusions...
The twist-lock brackets can be good enough, if they are well-enough made and correctly installed. The ones on my wrinkly blind were utter crap. The mid-span ones on the roller blinds were actually much better made.

Installation: as others have said, they need to be in a straight line, and vertically pretty level, in order to correctly engage in the slot of the blind. There is a certain amount of tolerance that can be achieved by flexing the blind, but not much.

When fitting the blind to them, you need be shoving the blind up with a fair force to ensure both wings on the twist-lock bracket go fully through the slot in the blind, and engage inside it. A common failure is to have only one wing engaged. The cam lever should start out pointing out towards you, and then rotate by a full 90 degrees to be flush with the blind, and lock with a firm feel.

Construction: The construction and tolerances on my wrinkly blind were utter crap.

With the bracket off the wall in my hand, I observed the following: with the wings in their engaged position in the slot, there was still sufficient fore-and-aft play for the thing to disengage. Vertical pull was just about OK, but any pull in the outward direction would disengage the blind from the brackets. Just crap design. There should not be anything like that play available when the wings are engaged. I bodged  some material into the blind to take up the free play in the locked position.

The second issue was that the wings were made of cheese, and were prone to bend downwards under modest load, thus making the twist-lock action very sloppy and not firm, and the corresponding friction between the bracket and blind was low, and this exacerbated the tendency for the blind to slip forward and off the front wing, as described above. I re-bent them so they sat horizontally for now at least.

But even now, I treat it very carefully, applying only gentle vertical pull on the cord.



Re: Roman blind keeps falling off cam/bracket
« Reply #10 on: 02 November, 2021, 01:43:30 pm »

The top of the blinds in my bedroom kept busting loose. Turned out the wall isn't flat, so the top bit of the blinds was being flexed to fit into the brackets and then this was enough force stored for it to then ping out when I used the chain.

The landlords shimmed some of the brackets out from the wall by a few mm, and it's totally fine now. Hopefully yours is a similarly simple fix.

Mrs Pingu

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Re: Roman blind keeps falling off cam/bracket
« Reply #11 on: 02 November, 2021, 04:46:11 pm »
I've been for another look. The brackets are carp. There isn't anything to locate the rear of the blind into really so it's mostly relying on it holding onto one lip.
The arm that closes the bracket on one end doesn't stay closed and flaps about, which will explain why it's always that end that falls off when I operate the blind and presumably the vibration opens the swing mechanism.

I wouldn't ordinarily bother with the blind but the surface of that particular window is significantly colder than the windows in the rest of the house so I assume it wasn't replaced at the same time and is probably leaking out heat quite merrily.
So I either attempt to buy a replacement bracket (potentially with little joy) or purchase a new roller blind that doesn't look like it should be in a nightclub...
Do not clench. It only makes it worse.

Re: Roman blind keeps falling off cam/bracket
« Reply #12 on: 02 November, 2021, 10:44:38 pm »
If it is a small window could you just add a secondary glazing sheet inside the frame?

Mrs Pingu

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Re: Roman blind keeps falling off cam/bracket
« Reply #13 on: 03 November, 2021, 03:49:51 pm »
Yes, I probably could.
Do not clench. It only makes it worse.