Upgrading Your Door Locks

February 26, 2019

ABS Lock

Why change your Lock?

Many UPV-C and generic composite doors have a standard cylinder in them, built to a budget that can easily be bypassed by someone who knows what they are doing in a very short amount of time. Having fitted over 1,000 composite doors, I would say over 70% of doors I take out have locks that are very old and outdated without features such as anti-snap etc. A lot of older cylinders don’t have the new technology that you get in todays more premium locks, such as anti-pick and anti-bump. It is a cheap way to upgrade your door to give you that peace of mind knowing you have the best lock available, it’s a good deterrent for anyone looking for an easy entrance, or to put a burglar off attempting to break in.

Internal image of ABS Lock

Lock Features

1. Anti Pick - This is the process of using something small and thin to manipulate the pins inside the lock so they are all aligned enabling the lock to turn and thus open a door.

2. Anti Bump - This is a method of trying to move the pins by bumping them. A special or similar type of key is inserted into the lock, it’s then hit and the energy transferred into the key makes the pins jump upwards for a very small amount of time in which the key is turned at the same time and the door can be opened. This is prevented with smaller pin stacks so the pins in the cylinder cant jump as far and setting the pins at different heights on the sheer line.

3. Anti Drill - This is the method of drilling the lock through the sheer line of a cylinder that completely destroys a lock enabling anything that can fit inside to turn the cylinder. This is prevented by the use of hardened steel, anti drill pins and ceramic plates.

4. Anti Snap - This is the process of snapping the lock in half in the centre exposing the internal components to turn the centre cam. Due to the nature of how a lock works and how its machined for the cam, it is a lot weaker in the centre. Modern locks are anti-snap which means the external part of the cylinder has a deliberate weak point (usually between between 10 and 20mm into the lock) so when someone tries to snap the lock to gain entry, it snaps at the intended weak point leaving the mechanism and centre of the lock untouched. Should a cylinder get snapped, it can still be unlocked using the correct key.

Ultion Lock

Which Lock to Choose?

There are loads of different cylinder brands. However, there are two locks that stand out to us from experience.

1. Avocet ABS / ATK
2. Ultion

Both locks are regarded in the industry as the very best. The Avocet ABS / ATK has a good proven track record for reliability, as well as maintaining all the security features, the Ultion lock is growing more and more popular and some would argue it is even more secure than an Avocet ABS / ATK. The Ultion lock has something called lockdown mode which locks the central cam in place if it detects the central cam is being tampered with. You can't go wrong with either lock, they are both great in terms of security and reliability and they cost roughly the same. 

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Inside an Ultion Lock
How to Measure a Lock?

Most locks on doors are very easy to take out and measure. On most UPVC and composite doors there will be a screw on the side of the door that screws into the cylinder.

With a tape measure, measure from the external side of the cylinder to the centre of the screw hole and do the same from the internal side of the cylinder.

You will end up with two numbers that may or may not be the same, i.e 45mm (internal) and 55mm (external), so this means your cylinder is 100mm in length but is offset, so you need to get a cylinder that is 45mm internal and 55m external. This is important as you need to make sure the cylinder goes back into the door correctly with the anti-snap on the external side.

It’s also worth noting that if your cylinder sticks out or is proud from the external handle, you can go for a smaller external sized cylinder, i.e if it sticks out 10mm from the external handle and the external size to the screw hole is 55mm, you can get a 45mm external cylinder and this will then sit a lot flusher with your handle.

How to install or remove a Lock?

1. On the side of your door, there will be a screw in-line with your lock. Usually a Phillips screw. Undo this and remove it completely.
2. Insert your key into the lock. Turn your key to about 10 o’clock or about 2 o’clock and pull the cylinder out.

To put the lock back in, its just as easy,

1. Make sure the anti-snap side is on the external side, some cylinders come with an anti-snap both sides, but the cylinder will say ‘EXT’ on it which means this is the external side.
2. Insert the key into the cylinder and turn the key so the black centre cam is flush within the cylinder, this will send slide right through your door.
3. Get the cylinder central within the door and put the screw back in to secure your cylinder.

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