Double door security bolt won't unlock with key

[Coco_M]

Hi experts,

There is a security lock at the bottom of these double door and it will not unlock with the key.

There is nothing showing on the other side of the door, and no space underneath the door (1-2mm).

How do I unlock it? I can't see anything in the small hole. The key turns and makes clicking sounds but it does not unlock.

Any help appreciated! Thank you.

[EricL]

Hello @Coco_M 

Thank you for sharing your question about your door's security bolt. I suspect that the internal mechanism of the bolt has failed and is preventing it from lifting the locking bolt that is in the ground. At the moment your door has an aluminium weather strip in front of it with a rubber sweeper at the bottom. I propose removing the weather strip so that you can access the bottom of the door. I propose using a small flathead screwdriver to try and lift the locking bolt while twisting the locking mechanism with your key in the opening direction.  

If after several attempts the bolt will still not rise, I suggest using a Multi Tool in combination with a Kango 3 - Piece Titanium Toughened Plunge Cut Multi-Tool Blade Set KOATV-3 or similar, the blade you choose must be rated for cutting steel. With this tool, you should be able to cut the locking bolt and uninstall the door. Please take great care not to accidentally cut the door or the floor.

If you are replacing the locking set you can either use a similar model such as the Gainsborough Satin Chrome Door Security Bolt or the Whitco Black Patio Bolt. Using the patio bolt means that you will need to drill a new hole in the floor or you can install it at the top and anchor it to the frame of the door. Please don't forget to re-install the weather strip.

Please make sure to wear gloves, goggles and a dust mask when cutting or working on your door lock.

Let me call on our experienced members @TedBear and @JoeAzza for their recommendations.

If you have any other questions we can help with, please let us know.

Eric

[JoeAzza]

@Coco_M @I have a similar lock, mine is installed on top of the door, if you can remove the hinge pins on the door, you will be able to remove the lock img mechanism, otherwise you will have to cut the the locking pin, as advised by @EricL , I have  attached photos of my lock and key

 

 I found this lock on the Bunnings website, hopefully it helps.

 also, please check if your key is worn out, you can buy a replacement key from Bunnings

 

[Coco_M]

Hi Eric,

Thank you for your response. I have removethe strip but the screwdriver or key do not do anything. There is max 2 millimeters between the door and the floor.

How thick is the blade tool and how do you use it please?

[Coco_M]

Hi Joe,

thank you for your reply. I have 3 keys and none of them make a difference.

These are the hinges. Where are the pins?

[EricL]

Hello @Coco_M 

Thank you for posting those photo updates of your attempt to remove the locking bolt. I was hoping that there would be enough space to wiggle the screwdriver and reach the locking bolt. But it looks like the space is really small. The pin in your door hinge is like a straight bolt that is holding the folding pieces of the hinge together. You can tap the hinge pin out by tapping it with a medium-sized nail and hammer from the bottom. However, before you make the attempt to remove it, please observe carefully from the bottom of the hinge if the pin can be actually tapped out.

I've placed an image below to give you an idea of how the pin comes out. Once the hinges are loose you can lift the door and gain access to the bottom locking bolt. 

Please make sure to wear proper safety equipment such as gloves, goggles and a mask when working on your door.

If you need further assistance, please let us know.

Eric

[TedBear]

Have you tried the simple approach of spraying the bolt and the mechanism with WD4O? Maybe it just needs loosening up a little, especially where the bolt goes down into the hole in the floor. 

[Noyade]

What a fascinating lock and key system! Never seen any thing like it. That 'key' looks like something that should be hanging in London Tower.

@EricLmentions you can buy replacement keys - does this mean the average thief/burglar could buy a key and then have access to all these locks, or is each key different in cross-section? The end is plastic moulded onto the steel pin?

@Coco_M  - to my eyes Coco, that hinge looks to be sealed at both ends? Stainless steel? You would need to angle cut one end off and then punch out the pin?

As far as that lock goes - 10mm steel rod? As per @EricLs thoughts with the multi-tool, or - - is there enough room for a 125mm angle grinder with a 1.2mm thick blade to fit and cut??

[Coco_M]

Hi Ted,

Thanks for the suggestion. I tried and failed.

[Coco_M]

Hi,

Yes the hinge is sealed at both ends...pretty but not helpful!

I think multi tool is the way but I don't know whether it will be thin enough to fit. Also I don't know how to use it.