Multi point locking mechanisms operate by either a key or lifting a handle, this action causes a metal plate behind the faceplate to move and engage the locking points, these two metal strips need lubrication along with other moving parts.
How I service a multi point lock
I start by holding the latch back by either turning the key or pushing the handle down, I can then spray above and below the latch to lubricate the main gearbox. (fig 1.) I then spray into the other gearboxes that operate any other locking points that come out of the mechanism, bolts, hooks, pins etc (fig 2.). To lubricate between the two metal strips you need to spray next to the rollers or into special oiling holes (fig3.). If the mechanism is fitted with rollers these need a little spray to keep them rolling. If the locking mechanisms has shootbolts at the top and bottom these sometimes get very rusty, its worth taking a file to remove the rust before giving it a generous does of oil to remove any remaining rust, make sure you put something under the end of the door to catch the oil as it will drip! I then operate the lock with the door open until it runs smoothly, this can sometime take a while especially if the door is not used often or water (especially salt water Fig 4.) has got into the mechanism. Once the mechanism operates smoothly with the door open I put a little vasaline on the latch and roller keeps (fig 5.), before trying it with the door closed. If the locking mechanism is very to operate or you have to force the handle up to turn the key then the door and mechanism need realigning, this is a job for an experienced locksmith, also if there is a gap around the door between the door and frame on either side the locking mechanism can be adjusted to pull the door in tighter preventing drafts and water ingress, again its best to get it adjusted by an experienced locksmith. Lastly is the lock itself, there is a lot of controversy over this if it is a new lock and straight out of the box then I would use a graphite powder but usually its been out in the weather and starting to rust so I use a small spray of oil, if you don’t intend using your lock from the outside and it faces the sea, then maybe a finger of vasaline might stop the water getting in?
I use WD40 with silicone it is described as “non-staining, hardworking formula which provides excellent lubrication, won’t attract dirt, and protects against moisture.”
Servicing a UPVC Window Mechanism
You need to open your window and move the handle whilst looking for all the accessible moving parts, I give them a good spray and then continue to operate the handle until it moves freely. If the window lock has shootbolts that