Wood paint on aluminium window frames

[PAR1969]

Long story but our new aluminium windows need to be painted. Our PM has purchased Jotun Demi Dekk Ultimate - however I can only see that this is a paint to be used on wood. What would be the implications of using a wood paint on aluminium 

TIA for any feedback x

[PeterW]

Is it painted aluminium ..? If so, you need a paint suitable to go over the top of the current coating. I doubt that what has been purchased is what is needed as DemiDekk is a wood stain not a paint. 

Edited August 9, 2018 by PeterW
It’s been a long day.....it makes sense now !

[Onoff]

I often paint bare

aluminum at home & work using Hammerite Special Metals Primer. Looks like red oxide. 

 

 

Edited August 9, 2018 by Onoff

[PeterW]

If these are being repainted as the PM appointed fitters have damaged them then I would want them painted by a specialist contractor as the warranty will be on the whole unit. 

[Onoff]

Just now, PeterW said:

If these are being repainted as the PM appointed fitters have damaged them then I would want them painted by a specialist contractor as the warranty will be on the whole unit. 

 

Just reread and saw they are already painted..... 

[Temp]

A wood stain won't work well on metal. Might not last first winter. I would get them professionally painted before fitting, probably powder coated but it won't be cheap. Check with the window manufacturer to see what they recommend.

Edited August 9, 2018 by Temp

[PAR1969]

 Can anyone recommend a suitable paint, the windows were ordered the wrong colour by the PM. It was picked up before delivery and we were advise by the PM he would put it right at his expense. We assumed he would advise the supplier and have them painted correctly prior to delivery. However he had them delivered the wrong colour now trying to paint them with the Demi Dekk paint 

Edited August 10, 2018 by PAR1969

[PeterW]

Who’s windows are they ...? If they have been powder coated then they need a different type of paint to a window that potentially has been painted previously. 

 

A call to the  manufacturer may be in order. 

 

The best way may be to identify the correct colour and have them sprayed - oddly you may find someone like a Dentmaster or ChipsAway a better solution as anything brushed will leave a less than acceptable finish. 

[Lesgrandepotato]

I think a grown up conversation with the PM about options is needed here. Before you do. How unacceptable is the colour to you? Is it a shade of grey? Or wholly inappropriate?

 

To make a decision - you’ll need a view from the manufacturer on what they’d use and how it affects the warranty. 

 

If he started painting before either either of these on my build then he may find himself in a career limiting situation as I’d have a serious loss of faith. 

 

There will be constraints in what can be done. They need to be understood and a decision made on approach / recompense. 

[Jeremy Harris]

First off, "painted" aluminium windows aren't often painted at all, as others have said, they are usually powder coated.  This is not paint at all, but a plastic covering that is applied by spraying the aluminium with powder (using an electrostatic charge to make it stick) then baking the coated parts in an oven to melt and cure the powder into the final surface.  The most common powder coats will be polyester, but you can also get nylon, epoxy and a few other types of plastic that are used for special applications. For example, an aircraft kit that I designed had to have the welded steel tube parts of the airframe epoxy powder coated, as epoxy will show cracks if the underlying airframe was damaged (an inspection and airworthiness requirement).

 

Only specific paints will be compatible with the powder coat on the windows, both from the perspective of adhesion and not attacking the underlying finish.  You need to get confirmation from the window manufacturers what the specific type of coating is on their product and their advice on refinishing.  Polyester powder coat is pretty common and compatible with most finishes, but to match the existing finish any new coating must be sprayed, and I doubt that anything other than a low VOC two pack finish will come close to matching the durability and quality of finish on the original widows.  Also, because of the way that the seals and glazing are fitted into an aluminium window I strongly suspect that either the whole window will have to be removed to be refinished properly, or at least the glazing and all window hardware will need to be removed.

 

Spraying two pack paint is also something that needs care, the right equipment and proper PPE.  It's not hard to do, and will give a finish that is pretty much the same as the original, which I very much doubt will be the case from any brush applied finish.

 

Others have mentioned the warranty, so you very definitely have to get advice from the window supplier on a way to refinish these windows that does not impact on the warranty.  Most aluminium windows will come with at least an 8 to 10 year warranty, so the last thing you need is for that to be adversely impacted by whatever refinishing method you choose.

 

I have to say that, if it we me, then I'd not even think about trying to refinish them.  I have the ability and kit to spray two pack and have access to powder coating facilities, but having a lot of experience with both, and knowing the work needed to get a decent standard of finish, I'd just get the windows taken out and replaced.  The last time I had a powder coat problem (a kit builder tried to repair scratches he'd made with paint) we ended up getting the whole component bead blasted back to bare metal and re-powder coated, as it was the only way to get a decent finish.