Mortice lock stiff to turn.

[Mal Travers]

Our mortice lock has gone from slightly stiff to turn to fairly stiff to turn over the last week. Any suggestions or should it be replaced? Mal

[ARWadsworth]

WD40?

[Mal Travers]

I wanted to be sure that it is OK to use. It is a relatively new door as all in our building were replaced as part of seemingly never ending Fire Precautions. Derek

[ARWadsworth]

Is it your door or a landlords door?

As it is a new door then WD40 will NOT help. Get the installers back in to fix it ASAP.

[Mal Travers]

Our door. Relatively new as in the last five years. Derek

[Woody]

Remove the lock, take off the cover, and very carefully remove the levers keeping them very strictly in order. Wipe each lever clean then coat lightly either with specific graphite grease for locks or with Waxoyl. Reassemble spreading a little more grease/Waxoyl on the bolt and its slide (may need to be done whilst the levers are out of the way.) Should fix the problem indefinitely.

I suppose you will now tell us that this is a 'continental' style lock that uses a Yale-type rather than a Chubb-type key? If so then remove the barrel (usually by removing one screw in the edge of the door and sliding out,) hold it vertical and squirt it with a Teflon based lubricant. Exercise the cylinder whilst it is still wet, then when all of the excess lubricant has run out replace the barrel in the door.

I have no doubt that I will now be seriously flamed, but I have used these techniques for years and have never had a lock cause any problem as a result.

[Mal Travers]

I had assumed that there would be a special product to use.

It has a chubb key.

I await their comments:-) If I conduct a search of all my junk I may even find a mortice lock that I changed in our last flat. Derek

[Harry Stottle]

If the door is exposed to strong sunshine, and with it happening over the last week, it might be that the heat is expanding the door, and causing a bit of misalignment of the lock.

[fred]

You haven't said whether this still applies when the door is open? If so then definitely open the lock up and take a look for binding or lack of lube (rare IME). As it's a lever lock mentioned below, these are exceptionally easy to remove and dismantle with usually a single screw holding on the backplate. If not then look for something constricting the bolt action, your door may have moved/warped with the recent change to better weather.

I've never heard of waxoyl being used, novel. I've never used a specific grease on lever type locks, in facts IME it's rare to need to add more, if the moving surfaces are in need of lube then there's usually enough displaced around the case to re-use. For a from scratch rebuild I use a molybdenum based grease but that's just because I have it around, it is the right consistency and it doesn't go off in air.

Agreed on teflon lube for cylinders, I wouldn't use WD40 unless to wash some other gummed up lube out of the pins. Blown graphite often sold for the purpose is bad too as it can set like concrete is washed through it.

Maybe practice the dismantling on that one if you're concerned with losing bits.

Good luck.

[fred]

In article , fred writes

And now for the answer to the missing words round, the answer is:

. . . if solvent . . . .

[Mal Travers]

No we have a Flat. Derek

[Andy Champ]

... will dry out to a nice, sticky, water-dispersant film (hence the name) which will make the lock even worse than it is now.

It's not a good long-term lubricant.

Andy

[Mentalguy2k8]

It could still be heat, my back door has 4 metal bolts that throw across into the metal frame when you pull the handle up to lock it, and it always gets stiff at this time of the year when the bolts and the frame expand. It's not in direct sunlight, but the ambient temperature is high enough to expand the parts. It's quite a precise adjustment, so even a small rise in the temp can throw it out enough to be stiff. It fits like a charm in Winter, I assume it was fitted and adjusted on a cold day!