13 replies to this topic

[Gaz66]

Is this a suitable primer for aluminium door skins?

[sonikk4]

I would recommend a etch primer for Aluminium and you could then add a coat of epoxy.

 

The primer we use on Aircraft Aluminium skins is normnally a etch based primer.

[Gaz66]

👍

[Icey]

Having just painted a load of Land Rover panels, you will need an etch primer. I use:

paints4trade.com

I then use their high-build primer as well before colour. All rollered and brushed on (you can spray it as well).

Edited by Icey, 14 May 2026 - 09:41 PM.

[DeadSquare]

Etch.

 

Aluminium etch primer is specially made for Aluminium because Aluminium very rapidly forms a thin oxide, which is beneficial as it is inert enough to protect against further oxidation, but it is also too inert to make a good key for most paints.

[pete l]

I was told never to 2k epoxy over etch primer.

[sonikk4]

I was told never to 2k epoxy over etch primer.

 

Well he is going to use 1k and i would be interested in the reason why not to use 2k over etch.

[pete l]

Apparently it can react after a while and crack under the epoxy. I'm just repeating what I was told not to do, because I was going to do it !

[68+86auto]

the TDS (technical data sheet) for the paint will say what the suitable substrates are.

[68+86auto]

There are 1k products which say epoxy in the name but it is quite different to the 2k epoxy primers people think of. It doesn't remotely do the same job. What you are looking at is probably basically an etch primer. For example the etch primer I use says in the datasheet, "epoxy modified". This is probably really the same as what you are looking at but the marketing team decided to jump in on the epoxy hype.

 

This stuff is better at sealing out moisture than a standard etch primer but is nowhere near a 2k epoxy primer.

 

I was told never to 2k epoxy over etch primer.

 

That is correct. Really it is ANY 2k product.

 

1k products slowly shrink and move over time on a tiny scale which causes issues with any 2k layers on the top. 1k can however go on top of 2k products.

 

The easiest way is to stick with one system.

 

Nobody should be painting 2k at home anyway. An air fed respirator and spray booth is essential for 2k. You do not want to play with Isocyanates.

Edited by 68+86auto, 18 May 2026 - 10:37 PM.

[pete l]

If the paint is so dangerous, why is it so easily available ? it doesn't even say it on the tin that it can kill you !

 

and then you see Brian from paint society using a standard 3M mask on youtube when he's using 2K at home.

 

I've repainted my mini with 2K and used a 3m mask and an extraction fan. It went well. I tried an airfed mask but couldn't really see after a while what I was doing through the glass 

[sonikk4]

Straight from the HSE website

https://www.hse.gov....on and training

 

A really big issue with any mask is its capability to fit your face. They may say such and such mask is the best thing ever, HOWEVER if it does not fit your face correctly then its useless.

 

Now a good quality forced air mask with removable films is the safest thing by far. As long as your air supply is up scratch and the filitration is rated then happy days. 

 

I dont care what anyone says on Facebook, Youtube or whatever. Unless they are a professional with the creds to back up what they are talking about remember one thing, you get one set of lungs in your life.

 

I hammer home constantly at work the need to wear masks when drilling Carbon Fibre or sanding it, its as bad for you as Asbestos. The same philosophy when using paint, we use a lot of 2k based paints in the Aviation indusrty. Extraction, Ventilation and correct PPE always.

[68+86auto]

If the paint is so dangerous, why is it so easily available ? it doesn't even say it on the tin that it can kill you !

 

and then you see Brian from paint society using a standard 3M mask on youtube when he's using 2K at home.

 

I've repainted my mini with 2K and used a 3m mask and an extraction fan. It went well. I tried an airfed mask but couldn't really see after a while what I was doing through the glass 

 

Most people just don't care about safety enough.

 

A lot of proper respirators will filter out isocyanates for a certain amount of time. By the time you can smell it, it stopped filtering them long ago. At the same time, the isocyanates are absorbed by your skin and especially eyes.

[Frisco]

If the paint is so dangerous, why is it so easily available ? it doesn't even say it on the tin that it can kill you !

 

and then you see Brian from paint society using a standard 3M mask on youtube when he's using 2K at home.

 

I've repainted my mini with 2K and used a 3m mask and an extraction fan. It went well. I tried an airfed mask but couldn't really see after a while what I was doing through the glass 

 

Drain cleaner will burn through your hand yet it's available over the counter. Dangerous products come with warnings about proper use, the can will have basic info and details on how to find the full product info.