UKC

Our front door has both a Yale and Dead lock.

Yale is fine with existing and new keys.

The deadlock is perfect with the keys we got with the house but we’re struggling with new keys.

We’ve had 3 done and none of them work well. The shop has redone them and made sure it’s as clean a match as possible but they don’t work.

They will lock with door with quite a bit of effort, but unlocking it, I can’t turn it enough to get it to open.

The newer keys are much sharper cuts but that seems to be the only difference. Does the lock just need replacing or is there a reason why the newer keys could be having issues given they can lock the door, just not smoothly?

edit- it will unlock but just with a lot of juggling and very little consistency.

I find that new keys always need some 'improvement' with emery paper.  That, and taking the weight off the bolt if the door exerts pressure on it one way or the other (ie push or pull the door as appropriate)

If in doubt, replace it. The last thing you want is a difficult lock in an emergency.

Have you tried a squirt of WD40 in the lock? 

I might try with some emery paper and if not then just replace it.

For a lock with handles I assume it’s a case of unscrewing the handles, pulling the bar out which connects inside and outside. Then unscrewing locking mechanism and removing it. Then reversing it all it with a new lock?

Graphite dust, it doesn't get sticky or turn to mud over time as dust gets in. Works magic in annoying locks.

OP: The problem is the keys you're getting cut are slightly inaccurate for some reason. I'd try finishing them by hand, see if that helps. Black the edge of your original with a marker pen so you can see if you take anything off it with the file (don't), clamp them together with the spines aligned then carefully file them to a good match. If they're too small already or the blanks are a poor match you'll need to try something else like a different key cutter.

jk

I had an issue a while back where I couldn't get keys that worked cut for a lock. It turned out that the one key I had that I was getting them cut from was very worn and only just acceptable. All the ones they cut from it were too far out. I solved it by removing the lock and taking it to the key cutting shop, where they diagnosed the issue and cut me some working keys.

If it's a wooden door that's probably the case, although it may only be the inside handle that's has a screw/Allen key. Remove that and the outer handle and bar come out in one piece.

If it's uPVC (although that would probably be a eurolock rather than deadlock) then it's normally just 2 screws on the inner door plate. There'll be plenty of useful stuff on YouTube for your lock type.

IME there can be various reason for new cut keys not to work well. Are the new keys identical to old in all aspects, including where the stop collar (or equivalent) is? Key length, shape, a stuck lever, etc, all can have an effect particularly if you have cut keys based on a well used key and well used lock. 

Removal - depends on the type of lock; some remove as you describe, others you can remove the lock barrel alone.

What I personally diy would do is take the lock out and try new keys in removed lock/barrel to see if that works or not. Then, “if”* it is one where the side plate can be unscrewed, open it up (keep it flat so nothing inside can move or fall out and be very careful not to dislodge or let anything anything shift when you have a look!). It is usually a very easy procedure. However, word of caution, if you are new to this suggest you take multiple photos/video of all stages as it’s very easy to convince yourself what went where at a later time!

* If as many can’t now be opened easily or have a separate lock barrel (mine do) and this can’t be opened/examined, but can probably be cleaned and lubricated.

Depending on what you see, it may be just badly worn, needing a clean, etc. Often you can insert the new key from the underside when it’s open and try it and see where it is failing (again care is needed not to dislodge levers etc, and some locks you just can’t do that on due to design).

The easiest alternative is to buy a new lock. This may be a full lock or could be just a barrel replacement (similar but different to Yale locks) depending on lock type. Just make sure it is identical in all aspects as regards to sizing to that you remove. If it doesn’t measure precisely the same, it may either not fit/work at all or may need some alteration to the door if this is possible.

Also, as a thought, if you are replacing the lock best check that it meets modern insurance requirements; generally as I’ve seen lately insurance requires min of 5 lever locks/ high security locks/etc, for cover for break in yet you can still buy basic 2/3 lever locks which would not cover any break ins.

good advice above, another thing to try before replacing the lock is a different place to cut the key . I live close to a small town where three differnet shops cut keys, all of them are rubbish at it and with old locks have an awful strike rate. In the nearby "big" town there is a van in the b and q car park called Mr. keys , his keys work every time . Its a 15 minute drive so about an hour im total to go and get a key cut but as they work every time, well worth the effort. ask around for your local mr keys. 

In my experience the better/best key cutters will ask how their keys were the next time you see them (if within a short enough time for them to remember you).

Thanks for all the help. In the end I found the same lock at screwfix for £25, so just replaced it. Newly cut keys are all working fine.

It used to be a holiday home so we should probably have changed the lock last year when we moved in.

As an aside, would it be difficult to change a barrel lock in a UPVC door to a thumb lock? First one was wooden so turned out to be nice and easy but I’m less sure on the other door…

Upvc ones are easy. Only thing to watch is that the cylinders come in various shapes (oval, europrofile etc) and different lengths, and can have a key on both sides or just one. Take the old one out, which is normally a single screw on the lock forend on the door edge and then take it to the shop to make sure you get a match.