Specialist hinges?

[JohnW2]

Hi there,

I'm trying to sort out a (very old) fairly large (about 1.2m x 0.8m) and heavy hatch onto a flat roof. Quite apart from the fact that the hinges of the lid are ancient and rusted to pieces, the hinging wasn't ('geometrically') very satisfactory ,anyway.

The diagrams below show the general idea of my current thinking. The pivot of the hinge presumably has to be on the outside of the lid (otherwise opening would be limited to 90°). In fact, it needs to be able open slightly more than 180°, in order that the lid can rest on the roof when it is open.

It probably wouldn't be difficult to fabricate what I have in mind, with a couple of (probably 3") hinges and some angle, although I might have to 'bend' the hinges a bit to get "slightly more than 180° '. However, I wonder if there are any hinges 'made for the job'. Standard 'cranked' hinges of an appropriate size (and strength) would probably do it, but virtually all the ones I have seen have been only 50mm and pretty flimsy. I therefore wonder whether I'm missing something, or if anyone can recommend some different approach.

Kind Regards, John

 

[foxhole]

You could only open to 110degrees and secure with chain?

 

[RandomGrinch]

Standard 'cranked' hinges of an appropriate size (and strength) would probably do it, but virtually all the ones I have seen have been only 50mm and pretty flimsy

Would something like this work?

https://www.ironmongerydirect.co.uk/product/rebated-storm-section-windowdoor-hinge-100-x-3mm-stainless-steel-pair-236038

Or...

Swing Clear Cranked Hinge

This cranked hinge is designed to open doors beyond the standard opening. Suitable for 44mm door thickness, it can hold up to 80kg and is available for 54mm thick doors (call our sales team). Includes bronze washers and fixing screws made from 304 stainle

www.sdslondon.co.uk

 

[JohnW2]

You could only open to 110degrees and secure with chain?

True, but without the pivot point on the outside, one can't even go beyond 90°, so I thought I might as well allow it to go all the way back and rest on the roof.

Kind Regards, John

 

[JohnW2]

Would something like this work?

Thanks for your interest. I've been seeing a lot of those like your first piccie (usually called 'storm hinges'), but haven't yet been able to think of how they could be used for my purpose - unless you have some ideas?

However, your second pic looks far more promising, so I've definitely going to look into that - so many thanks!

Kindest Regards, John

 

[JohnW2]

True, but without the pivot point on the outside, one can't even go beyond 90°, so I thought I might as well allow it to go all the way back and rest on the roof.

I should have added - I do intend to have some sort of chain, as suggested, not the least to make it easier to close it from below, but I thought it would sometimes be useful to be able to 'unhook the chain and fold it right back.

Kind Regards, John

 

[JohnW2]

Or...

Swing Clear Cranked Hinge

This cranked hinge is designed to open doors beyond the standard opening. Suitable for 44mm door thickness, it can hold up to 80kg and is available for 54mm thick doors (call our sales team). Includes bronze washers and fixing screws made from 304 stainle

www.sdslondon.co.uk

Ah - definitely promising, but I'm not so sure about £108 for a pair of hinges However, now I've seen what they are calling them, maybe I might be able to find something similar at a more acceptable price!

Kind Regards, John

 

[RandomGrinch]

I've been seeing a lot of those like your first piccie (usually called 'storm hinges'), but haven't yet been able to think of how they could be used for my purpose - unless you have some ideas?

I wondered if there would be enough offset, if they were mounted like this?:

However, now I've seen what they are calling them, maybe I might be able to find something similar at a more acceptable price!

Yes, they are a bit pricey!
I think something like "Stainless Steel Swing Clear Hinge", may be a good search term to start with.

 

[JohnD]

I wonder if a cranked hook and band hinge would do? It puts the hinge pivot outside the plane of the door or hatch.

Galvanised ones are very durable if you paint them before fitting.

 

[JohnW2]

I wondered if there would be enough offset, if they were mounted like this?:

Yes, I suppose that is a definite possibility - I need to look carefully at the dimensions - and, as I said, there are lots of them around (at sensible prices) for me to look at and choose from.

Yes, they are a bit pricey! I think something like "Stainless Steel Swing Clear Hinge", may be a good search term to start with.

It seems as if "Swing Clear" as part of the description is very much US terminology, since the vast majority of hits one gets when searching for anything which contains those words seems to be in the US - and, quite apart from the very high 'postage' figures, some of the prices are even sillier than the one you cited and, in fact, are often nothing more than the 'storm hinges' (available cheaply in UK) discussed above - such as (and the price appears to be for one hinge, not a pair!) ....

Kind Regards, John

 

[JohnW2]

I wonder if a cranked hook and band hinge would do? It puts the hinge pivot outside the plane of the door or hatch. Galvanised ones are very durable if you paint them before fitting.

Thanks. Yes, I've been getting a lot of variations on that theme whenever I search with 'cranked' in the search term, and have been pondering whether I could easily make use of them.

Kind Regards, John

 

[JohnW2]

I wondered if there would be enough offset, if they were mounted like this?:

I found a few with detailed dimensions, and it looks as if they might well work. Nearly all the ones I've seen have been 63mm (2.5") but maybe three or four of them would do the trick. Most are dirt cheap, so I'll get some and do some playing!

Thanks again. As I said, I'd looked at these quite a bit, but didn't get my head around how they could be used to achieve what I wanted - I think I had the fixed idea in my mind that the leaf of the hinge would have to attach to the outside of the lid - although I now realise that it's only the offset of the pivot point that matters, not what the leaf of the hinge is attached to!

Kind Regards, John

 

[robinbanks]

Why not attach an angled strip to the frame and attach a normal hinge to that?

Please excuse the crudeness of the diagram; not easy to sketch on a phone, my stylus has gone walkies :

The angle need only be the same as what the lid makes with the floor when it rests on it (assuming everything else is 90) - any steeper and it requires the hinge to open out more, any less and the hinge will close before the lid touches the floor, so you can work the angle to the capabilities of the hinge (you'll need a hinge that opens further than 180 degrees, I'm sure it's easy to find up to 270, which will be more than enough)

 

[foxhole]

Repaired a hatch like that , the weight of the hatch together with it not quite being supported when opened ripped the hinge screws out .

 

[JohnW2]

Why not attach an angled strip to the frame and attach a normal hinge to that? .... The angle need only be the same as what the lid makes with the floor when it rests on it (assuming everything else is 90) - any steeper and it requires the hinge to open out more, any less and the hinge will close before the lid touches the floor, so you can work the angle to the capabilities of the hinge (you'll need a hinge that opens further than 180 degrees, I'm sure it's easy to find up to 270, which will be more than enough)

Thanks. That was my 'Plan A' (which is certainly still on the table) As I wrote ....

It probably wouldn't be difficult to fabricate what I have in mind, with a couple of (probably 3") hinges and some angle, although I might have to 'bend' the hinges a bit to get "slightly more than 180° '. However, I wonder if there are any hinges 'made for the job'. ..........

The 'storm proof' hinges (as mentioned by RandomGrinch), which are readily and cheaply available (albeit only in fairly small sizes), are effectively the same as you/I propose, one part of the hinge effectively being the "angled strip".

Kind Regards, John