How can I drill through a metal door frame?

All good on the list though hold off on the chisel as you might not need it. And if you did need to knock away anything it might just need an old screwdriver..

and just as an FYI, the first chisels link is for a phatic hammer drill. The Kango one is fine, but too expensive for your needs. This would be better.

Nailbag

All comments

Hello @pauloguanaes

Welcome to the Bunnings Workshop community. It's sensational to have you join us and thanks for sharing your question about your door knob installation.

I propose using a Diablo 20mm Bi-Metal Hole Saw to cut the hole in the steel frame. Your goal is to cut the steel first and when you have it out of the way, you can then address the concrete inside the frame should there be any. A standard narrow chisel and hammer should enable you to create a hole big enough to allow the latch to settle in. I suggest using a steel file to adjust the hole size if you need more space. Please check the size of the latch so that you get the correct size metal hole saw.

Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.

If you need further assistance, please let us know.

Eric

The metal door frame is quite thick of around 4-5mm and made of hard galvanised steel. You need to be very accurate when starting your holes and the slippery surface makes this a little more challenging. The striker plate will be surface mounted not rebated like the edge of the timber door. So we need to be a little more specific on the dimension for the cavity cut out. I have supplied a drawing below as a guide.

Invest in a centre-punch to make dead centre for both the hole-saw and pilot holes for the striker plate screws. You will need to use a 14mm bi-metal Holesaw to make two slightly overlapping holes. Use high-speed on your drill with light pressure. Hold the drill firmly with both hands. As you break through the saw will jamb, so expect this. Continue with lighter pressure until through. Then a metal file to square off the opening. When buying the Holesaw, check it fits your arbour.

Hopefully the cavity of the frame is deep enough to accomodate the deadbolt. Otherwise you might be faced with either or both some rough brick mortar and brick to chisel out slightly.

The striker plate screws supplied are only suitable for wood, so you will need to replace them with metal ones. They must be self-tapping ones or they will snap or get jammed when driving in.

Nailbag

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Dave-1

Good Morning @pauloguanaes

I really cant add more to the instructions then @EricL and @Nailbag 's ones 🙂 They are the same steps I would take. Only thing I can add really is take it easy, slow and patient type deal, especially if you have to use a file to fix up the hole. If you feel it isnt going anywhere, take a step back, grab a coffee or tea and then come back and continue, ever little bit more is one bit less to get through the next time.

Nice work on the wooden set tho 🙂

Dave

Thank you Eric, Nailbag and Dave for the tips.

@Nailbag Quick questions:

I'm adding a picure of the Strike below. It comes with 2 parts - internal and external. The internal looks like a T and has a more rounded hole. The external has a retangular one, as in your drawing. As the door frame is metal, do I still need a strike? Can't I just make a hole on the metal and mortar and use a metal file to smooth the edges up?
Would that reduce the level of security of the deadbolt?
I'm saying that because, as you pointed out, I can't carve the metal frame to accomodate the strike plate on the frame and on this case, there are 2 parts, so double the thickness.
Last one - the RYOBI kit I bought is designed for wood and metal doors. Can't I use it's 25mm white holesaw (first picture) to cut through the metal frame?

Thank you!!

Hello @pauloguanaes

Let me tag @Nailbag as well to make them aware of your questions. I believe it should be ok not to use the striker plate as the deadbolt will not be striking the corner of the door frame unlike the latch of the door handle. Since the door frame is made of steel, I don't think it will reduce the amount of your security. The striker plate when attached to a timber frame adds a certain amount of reinforcement, but this would not matter to a steel door frame. As for the hole saw unless it's tagged as bimetal then it is only designed for cutting wood.

If you need further assistance, please let us know.

Eric

Yes you could go without the both the internal and external parts of the striker plate and the level of security wouldn't be impacted as you have a steel frame. It just comes down to a neater level of finish by just fitting the outer one. The inner one needs to be rebated in which you can't do with a steel frame.

Yes you can use the 25mm hole saw, it's just making the hole bigger than it needs to be and the outer striker plate won't cover it on the sides. Without the plate and if the door handle was unlocked the door would have front and back movement making it easier to possibly force the door open. The door if its a hollow core will fail before the latches to. Again another reason that you install the outer striker plate, which is easy as its only going to sit on the top of the frame.

I'm just a stickler for finish, but I also have more tools and experience. And this is a tough DIY job, so you're doing very well to have a go at this project.

Nailbag

Thank you, @Nailbag!

I'll install the strike plate and get a smaller hole saw as you suggested.

So, to sum up what I need to buy is:

Centre Punch
14 mm bimetal holesaw
Metal file
Self-Tapping Screws for metal
Masonry Chisel for the concrete inside the frame - can I use this "drill bit" one? https://www.bunnings.com.au/craftright-3-piece-sds-chisel-bit-set_p6360033 Or this one is better for the job? https://www.bunnings.com.au/kango-3mm-masonry-chisel_p0472205

anything else Im missing?

Thanks!

All good on the list though hold off on the chisel as you might not need it. And if you did need to knock away anything it might just need an old screwdriver..

and just as an FYI, the first chisels link is for a phatic hammer drill. The Kango one is fine, but too expensive for your needs. This would be better.

Nailbag

Thank you, @Nailbag . I'll do it this weekend.

Now, I thought that the instalation of the deadbolt would be more strightforward in my front door, but I'm not so sure anymore.

Its a wooden door but it's a french or double door (I don't know exactly the difference) and I'm not sure what's the best approach here.

Please have a look at the pics below. The current latch has kind of a metal frame around it and I couldn't find something similar online for the deadbolt. Also, how can I cut the door frames like that to install the deadbolt?

WhatsApp Image 2025-06-07 at 07.43.59.jpeg

JacobZ

Hi @pauloguanaes,

The metal enclosure is called a rebate kit, like this Gainsborough Rebate Kit. There is a variety available for different locks and finishes.

If you can let me know which deadbolt you are looking to use, I would be happy to see what is compatible.

To cut out the rebate, a locksmith or carpenter would use a sharp chisel or a multitool. You would mark the location of the lock using a pencil, then cut away the material so the striker plate or rebate kit sits correctly in the door. It is reasonably easy to do, you just have to mark it carefully and take care not to cut outside of the markings.

Let me know what you think.

Jacob

That rebate kit @JacobZ has linked in is perfect. In fact I'm glad its been mentioned as I didn't even know they were available and always made my own.

The only point I can add is to ensure when measuring the 60mm backset for the deadlock, is that its measured from the furthest edge of the door.

Nailbag

Screenshot 2025-06-08 at 3.10.08 pm.png

Hello @JacobZ ,

Thank you for your tips.

Originally, I was trying to find a smart lock with handle to replace the Gainsborough but I couldn't find anything that would fit its original setup.

There's a Gainsborough smart lock that would fit, but it's too expensive.

The Deadbolt I will install is a ultraloq u-bolt pro wifi (image below). Would that Rebate you posted the link work with it? Thanks.

Hello @pauloguanaes

There is a very good chance that the rebate kit will fit, but before you purchase anything, I suggest using the existing rebate set that is attached to your door already as it might fit as well.

If you need further assistance, please let us know.

Eric

Hello @EricL ,

I'll keep the current door handle as it is and I'll add the deadbolt above it, so I'll have to buy a new rebate.

So, what would be the steps here, after I buy the rebate?

Marking where the bore hole and latch hole will be drilled using the Ryobi Wood And Metal Door Lock Kit
Then, should I drill the bore and latch hole and then use the chisel to make room for the rebate? Or rebate first and then the holes where I marked previously?
On the other door, same question. Drill the strike hole first or chisel the door for the strike plate?

Thank you,

Hello @pauloguanaes

I agree with your first and second steps, mark the bore hole where the latch hole will be drilled. Once the bore hole and latch hole have been drilled you can now position the rebate and mark it with a pencil before you use your chisel.

For the third step once the rebate is installed close the door and spot the position where the rebate will be sitting in relative to the other door. Mark the position with your pencil then chisel out the spot before you drill the strike hole. My best advice is to make sure that the latch and rebate are in alignment and the same goes for the other door. In this manner the doors deadbolt latch will line up with the hole on the other door.

If you have any other questions we can help with, please let us know.

Eric