How to re-paint metal window frames, inside and out?

Question

Hi everyone,

We're looking at repainting our metal window frames and sliding doors, internal and external, to update the old yellow cream colour to a slightly fresher and more modern colour. Probably just white or Colorbond Surfmist.

I've seen a couple of other posts about this, e.g. https://www.workshop.bunnings.com.au/discussion/176712/how-do-i-paint-over-metal-window-frames

However, I still have a tonne of questions. Would love to hear people's thoughts and experiences.

- What primers and paints are best, noting we'll want these to be durable and suitable for external frames as well as internal?

- We have some areas of rust - Do these need a going over with a steel brush / wire wool / sand? How much of the rust do i need to remove, all of it?

- Is something like Cold gal primer the best thing to use on the rust areas? Is the brush on stuff any better than spray or doesnt it matter?

- What grade of sand paper should I be using? Ive seen different grades in different posts. Presumeably it just needs a light sand to key the surface, it doesn't need taking back to the metal?

- Is it worth getting a HVLP spray gun for such a big job? We may end up doing gutters and garage door as well. Are the various primers and paints compatible with this (i.e. can be watered down)?

- How do people mask off or work around the hardware and fiddly stuff like locks, handles, clips, door felts, etc? I can't see how these can be removed but also look like a complete nightmare to tape off precisely.

- For fly screens, is it simply easier to take off the mesh screens and rubber spline and put new stuff on after painting the screen frames?

Any other tips appreciated!

Thanks in advance from someone who is probably overthinking this!

projectmumdanni · Answer

hi Joe. I used paint and brush for the frame on our exterior window frames.  I found spray paint to work better on the screens and screen doors so you don’t get that paint build up in the screen. Definitely recommend sanding and using a primer. I didn’t on our front screen door and general wear and tear the paint is wearing off.

joe_edgell · Answer

Thanks @JacobZ, appreciated

JacobZ · Answer

Hi @joe_edgell,

You've certainly done your research and have hit on the key points, but I do think you are overthinking it a little bit, which is great because it means you are prepared, but it is actually a pretty straightforward process once you strip it back to basics.

Start with a light sand using 120 grit. You are not trying to take it back to bare metal, just knock the surface back and give it a key so the new paint sticks properly. Anywhere with rust, give it a bit more attention to remove the loose material.

Once that is done, clean everything down properly with some sugar soap to remove dust, dirt, and any grease.

For any remaining rust, apply a rust converter. You do not need to get every last bit back to shiny metal, just remove what is loose and treat what is left so it does not keep spreading.

After that, apply a suitable metal primer such as

https://www.bunnings.com.au/dulux-4l-precision-all-metal-primer_p1400884

. This gives you a solid base and helps everything bond properly, especially on those previously rusty areas.

Then you can paint. A good quality enamel paint such

https://www.bunnings.com.au/dulux-4l-aquanamel-semi-gloss-white-enamel-paint-4l_p1400051

as will do the job. Using a brush and small roller is usually the easiest way to get a nice finish without making things overly complicated. Adding a bit of

https://www.bunnings.com.au/flood-1l-acrylic-paint-conditioner-1l_p1560666

can also help the paint level out better and reduce brush marks.

A spray gun can give a great finish, but in reality, the amount of masking and prep needed around glass, brick, seals, and hardware usually outweighs any time you save spraying. For most people, a brush and roller with a bit of paint conditioner to even out the paint end up being quicker and far less hassle.

For masking, just keep it simple and take your time with painter’s tape around the glass and any hardware you cannot remove. If you are painting with a brush and roller, most handles and locks can be worked around without too much trouble, and any errant paint can be removed quite easily with a damp cloth while still wet.

With flyscreens, it is usually easier to remove the mesh and spline and replace them after painting rather than trying to mask them off.

Take your time with prep and keep the process simple and I am sure you will get a really good result.

Let me know what you think and if you have any further questions, please don't hesitate to ask.

Jacob