How to paint rusty metal door frames?

[LivMitch]

Hello there, 

I am prepping and painting:

• 6 internal wooden doors (painted with oil-base) 
• All have metal frames (painted with oil-base) - some rusty patches
• 1 bath patch – 5-cent coin size, rusting around edges of a previous repair (used Selleys Application Touch Up). 
• photos of all below.

Sanding

• What grit sandpaper do I use on oil-based paint metal door frames?
• How smooth does it have to be? I'm doing it by hand (1960s multi-indented
• What grit on wooden doors?

Rust 

• After applying rust converter (metal frames) how long should I wait to paint?
• Re bath repair, do I attempt to scrape off the old Selleys repair? (Seems solid, don't want to risk a hole/damage.)

Undercoats

• Metal frames and wooden doors – is Dulux Ultra Air Primer OK? 
• 1 or 2 undercoats (existing paint is cream, I'll paint a warm white)?

Topcoat

Is 1 top coat Taubman’s Ultimate Enamel metal frames and wooden doors OK? 

Hinges

I can’t take the doors off myself, they're too big/heavy.  Hinges are all heavily painted, some rusting.

• How do I do tackle hinges - do I strip them using turps or try a wire brush? 
• Would it be useful to apply graphite or WD40 before painting them or after?

Thanks so much for your help.

Liv

heavily painted hingedoor frame and doorframes).

re

[EricL]

Hello @LivMitch 

Thank you for sharing your question about painting your metal door frames. Before you begin, I suggest checking for rust bubbles along the frame of the door. These will usually have slightly raised oval indentations on the body of the steel door frame. I recommend using a hammer and lightly tapping any bubbles you see along the frame of the door. These areas will need extra sanding to make sure that the rust is thoroughly removed.

If you are not keen on manually sanding the surface, I suggest investing in an electrical sander such as the Ozito 200W Multi Sander Kit. This has 3 interchangeable bases that will allow you to do large flat surfaces and detail work. It comes with a standard packet of sanding sheets that will allow you to tackle sanding jobs easily. I recommend using 240grit sandpaper to get a textured surface for the primer to get a grip on.

Please note that the 240grit sandpaper will also work on the timber door.

Once the frame has been properly sanded, your next step is to clean the painting surface down with Sugar Soap. Wipe the frame down with a clean rag and fresh water to remove any residual Sugar Soap and let it dry off. I recommend using Dulux Precision primer, and once that has cured according to instructions, a water-based enamel topcoat in your choice of colour. The Precision primer is a specialty product designed for hard to paint surfaces and is ideal for these types of surfaces.

I suggest leaving the bath repair at the moment unless you are prepared to repaint the bath as well. In the meantime, I suggest holding off on this project until you 've completed your door frame repainting project.

In regards to the rust converter, some products state that they dry off in 20 minutes but require 24 hours to cure. Please check the label of your product and follow the instructions.

The Dulux Ultra Air Primer is ok for the timber door, but it is better to use the Precision Primer on the metal frame. A minimum of two coats is recommended so that the old colour beneath is totally covered. 

The Taubmans Ultimate Enamel should work fine with both primers as they are both water-based. As for the hinges, it's up to you if you want to sand the paint off to reveal the original hinges. However, if the paint has overhardened due to age it might not be worth taking off as it might peel off more of the paint on the body of the door causing more repair work.

Using WD40 should be ideal to keep the hinges properly lubricated.

I also suggest having a look at these discussions:

• How to repaint metal door frames? by @ATR 
   
• How to paint metal door frames by @homediynoob

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

Eric

[LivMitch]

Hi Eric,

Thanks so much for your thorough and very helpful reply.    I'll get to it with all your suggestions.  

Thanks also for the Ozkit sander suggestion but I tried it twice on my last painting DIY (a borrowed Ozkit sanding kit with new pads and then brand new Ozkit sander and more new sanding pads). Neither Ozkit was better or faster than hand-sanding.  The sanding pads simply would not stick to the black base despite buying several new packs of to ensure they weren't 'off' batches.  They kept vibrating off every minute or so, very frustrating. I'll see if I can hire a commercial sander this time.

Again, appreciate your help. 

Liv

[EricL]

Hi @LivMitch 

Sorry to hear that the Ozkit did not work out. A good alternative would be to use the Ozito ¼ Sheet Orbital Sander. This sander does not need special sanding pads and will work with ordinary sandpaper panels. 

Please keep us updated with your progress, we look forward to seeing your door frames freshly painted.

Eric

[LivMitch]

Hi Eric,

I tapped the rust on the doorframe as suggested and it became a 2cm-long hole! 

Do you have a magical 'filler' repair for this? Some kind of tape perhaps?

See photo: Top section is rust, and bottom circled section is a hole.

I suspect there's two more small holes in this frame from a shower-membrane leakage (15 years ago) on this shared wall, which was fixed, but this must be collateral damage).

Fingers crossed,

Liv 

   

[EricL]

Hi @LivMitch 

It's better to find out about the rust spots now rather than have them appear on the frame after you've painted them. I suggest sanding down the rust spot edges as best you can and clean the area of debris. I then recommend using Turbo 500ml Metal Builders Bog. My number one tip when using this product is not to use too much activator. Excessive use of the activator will accelerate the curing time of the bog and will prevent you from shaping and flattening the surface.

If you need further assistance, please let us know.

Eric

[LivMitch]

Thank goodness for Bog.  Much obliged Eric. 

I'll follow the instructions but if you think that would advise using 'too much' activator, I'd be grateful for your further confirmation.

Liv Just back from Bunnings with my new door knobs (after locking myself inside my flat)

Home DIY . . . What an adventure!

[EricL]

Hi @LivMitch 

Yes, just to confirm, don't use too much activator to prevent the bog from curing too fast. We look forward to hearing more of your D.I.Y adventures.

Eric

[LivMitch]

Eric,

Do you recommend 1 or 2 top coats of water-based enamel for a metal door frame?

Is semi-gloss OK or should I go for something flat?

Thank you

Liv 

[EricL]

Hi @LivMitch 

Two coats are always recommended when applying the topcoat. Aside from the extra protection it gives you a uniform finish on the surface. Using semi-gloss is ok as it repels dust and dirt better.

If you need further assistance, please let us know.

Eric