Nidus Lonsdale Door Hardware

Nidus Lonsdale door hardware buying guide

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Nidus Lonsdale is a range with a round backplate and a radius lever end, finished in brushed nickel. This collection holds the Lonsdale Eurobolt, a door bolt sold as a single cylinder and as a double cylinder, each in a brushed nickel visual pack. The bolt is zinc alloy, the backplate is 70mm across and the design is non-handed, so it fits either side of the door. This guide explains what the Eurobolt is, how the single and double cylinder versions differ, which measurements decide fit, how to choose between the two, and how to fit and look after one. The wider Nidus range is on Nidus door hardware.

What the Lonsdale Eurobolt is

A Eurobolt is a bolt that locks a door with a key cylinder. It sits on the face of the door behind a round backplate, and the bolt slides into the frame when you throw it. It is used with a latch or a lever set, so the lever handles ordinary opening and the Eurobolt locks up. The Lonsdale version is matched to the Lonsdale design, with a round backplate that echoes the round rose on the lever sets, and a radius end that follows the lever shape. On a door with Lonsdale levers the bolt looks like part of the same set.

The two versions

Version	Cylinder	Use	Door thickness	Backset	Backplate
Eurobolt single cylinder, brushed nickel	Single	Privacy, with an inside turn that projects 46mm	34 to 45mm	60mm	70mm round
Eurobolt double cylinder, brushed nickel	Double	Entrance, key on both sides	34 to 45mm	60mm	70mm round

Both are zinc alloy in brushed nickel, and both include a latch set at a 60mm backset. The two differ only in how the lock works from inside.

Single cylinder: the privacy version

The single cylinder Eurobolt has a key cylinder on the outside and a turn on the inside. The turn projects 46mm from the plate, enough for a hand to take hold of and turn without effort. Use it where the person inside should be able to lock and unlock the door without a key. It suits a bedroom, a home office, a study or a back door with no glass beside it. A household member can leave quickly, and the lock still stops a visitor from outside.

Double cylinder: the entrance version

The double cylinder Eurobolt has a key cylinder on both sides. It is made for an entrance door, and it suits one with glass in the leaf or beside the frame, where a turn on the inside could be reached by breaking the glass. The key is needed from inside as well, so keep one near the door where everyone can find it, and do not leave it in the cylinder. If the door is an exit in a rental, a strata building or a business, check the exit requirements before you choose key operation from inside. When in doubt, choose the single cylinder.

The round 70mm backplate and the 54mm hole

The backplate is a round plate 70mm across. It is made to cover a standard 54mm cross bore, which is the large round hole drilled through the face of a door for a lock or a lever set. A 70mm plate leaves an 8mm margin on every side of a 54mm hole, so the edges of the hole stay out of sight and an old hole with a slightly rough edge is hidden. If your door already has a 54mm hole, the Eurobolt goes over it. If it does not, the door needs a new hole, and the hole size is the first thing to confirm.

Non-handed design

The Lonsdale Eurobolt is non-handed. A handed lock is made for a left hand or a right hand door, and the wrong hand will not work. A non-handed lock works on either, so one product suits every door in the house, and it does not matter which way the door swings. That also makes it simpler to order, because you only choose between single and double cylinder.

Door thickness: 34 to 45mm

The Eurobolt suits doors from 34 to 45mm thick. That range covers most internal doors and many external doors, but it is narrower than some locks, so measure the door at the edge before you order. A solid timber entry door can be thicker than 45mm. A hollow core door can be thinner than 34mm. In either case this Eurobolt is the wrong fit. If your door is thicker, the Zanda Jura deadbolt fits doors from 32 to 50mm and is on Zanda Jura cylinder deadbolt.

Backset: 60mm

The backset is the distance from the edge of the door to the centre of the hole. The Eurobolt has a 60mm backset, which is the most common position on Australian doors. Measure from the edge of the door to the centre of the existing hole. If it is 60mm, the Eurobolt matches. If it is 70mm, this lock does not suit the door, and a lock with an adjustable backset is the better choice.

Brushed nickel in zinc alloy

The Lonsdale finish is brushed nickel, a soft silver with a fine directional grain. It reads as a quieter alternative to chrome and hides fingerprints better. The body is zinc alloy, which holds a plated finish well and keeps its shape. Brushed nickel suits white, pale grey and timber, and it sits well with stainless steel hinges and nickel stops. For nickel hardware across a house, see brushed nickel door handles.

Choosing between the Lonsdale and the Jura

Both are cylinder deadbolts in brushed nickel. They differ in shape and in fit.

• The Lonsdale has a round 70mm backplate with a radius end, and the Jura has a traditional cone shape.
• The Lonsdale suits doors 34 to 45mm thick and has a 60mm backset, and the Jura suits 32 to 50mm and has a backset that adjusts from 60 to 70mm.
• The Lonsdale is zinc alloy, and the Jura is brass.

Choose the Lonsdale when the door already carries Lonsdale or Nidus hardware, or when you want a flat round plate. Choose the Jura when you need a wider door range or an adjustable backset.

Fitting a Lonsdale Eurobolt

The installation instruction sheet for the product has the hole sizes and the fixing order, so work from that. The general sequence is as follows.

1. Check the door thickness, the backset and the 54mm hole.
2. Mark the position at a comfortable height, clear of the existing latch and any glazing.
3. Fit the latch into the door edge and fix its faceplate.
4. Fit the cylinder and the backplate on each face, and fix them together.
5. Fit the strike plate to the frame and check the bolt lines up.
6. Test the key, and the turn on the single version, with the door open and then closed.

A deadbolt is only as strong as the frame it meets. Fix the strike plate firmly and check the frame is sound.

Replacing an old lock

When you change an old lock for a Lonsdale, check that the old holes match. The 54mm cross bore and the 60mm backset are the key figures. Check the paint around the old lock as well. A smaller old plate may leave unpainted door around the new 70mm plate, and a larger one will leave a mark that the new plate does not cover. A touch of paint tidies either.

Matching the rest of the Nidus range

The Lonsdale belongs to the Nidus family. Check Nidus door hardware for matching levers and parts, and see the other Nidus ranges on Nidus Collins door hardware, Nidus ATZ door hardware and Nidus spring door hardware. Deadbolts from other brands are on deadbolts.

Reading the product names

The two products are the Nidus Lonsdale Eurobolt Single Cylinder Brushed Nickel Visual Pack and the Nidus Lonsdale Eurobolt Double Cylinder Brushed Nickel Visual Pack. Nidus is the brand, Lonsdale is the range, Eurobolt is the product, Single or Double is the cylinder and Brushed Nickel is the finish. Each pack holds one Eurobolt. Choose between the two by how the door is used, because nothing else changes.

Where the bolt sits on the door

Fit the Eurobolt above the lever or the existing latch, at a height that is easy to reach and clear of any glazing bars or panel mouldings. Line the backplate up with the lever rose so the two plates sit on one vertical line, which is what makes the door look finished. The bolt and the latch should not share a hole or crowd each other, so check the space between them before you drill. On a door with a lock already fitted, the Eurobolt adds a second locking point rather than replacing the first.

Using the lock day to day

On the single cylinder version, turn the inside turn to lock the door when you are at home, and use the key from outside when you leave. On the double cylinder version, lock with the key on either side. Check that the bolt is fully thrown by pushing on the door. A bolt that sits half out does not give the protection of a fully thrown bolt, and a door that has dropped slightly on its hinges is the usual cause.

Questions people ask

Does the Eurobolt include a latch? Yes, a latch with a 60mm backset.

Can I fit it on a left or right hand door? Yes, it is non-handed.

Does the single cylinder lock need a key from inside? No. It has a turn on the inside.

Is it for a front door? The double cylinder version is the entrance version. Check the exit rules for the building first.

Care

Wipe the brushed nickel with a soft damp cloth and dry it. Avoid abrasive pads and strong cleaners, which dull the finish and can wear the plating. Keep the keys clean, and replace a worn key early. If the bolt starts to stick, check that the door has not shifted and that the bolt still lines up with the strike plate.

Common mistakes

Check these before you order and again before you drill.

• Ordering for a door thicker than 45mm or thinner than 34mm.
• Ordering for a 70mm backset.
• Choosing a double cylinder for a required exit.
• Leaving the key in the inside cylinder.
• Fixing the strike plate into a weak frame.

Our recommendation

Choose the single cylinder Lonsdale Eurobolt for a door where everyone inside should be able to leave without a key, and the double cylinder for a door with glass in or beside it. Check the door is 34 to 45mm thick with a 60mm backset and a 54mm hole, keep a key near the door on the double version and match the brushed nickel finish to the levers and hinges.