Any advice on painting aluminium spars? I stripped the boom and cleaned it up.

The corrosion barriers have broken down over time and some very minor corrosion has set in.

So rather than just renewing the barriers I was thinking of spraying the boom in 2-pak paint, starting with an epoxy primer. I have sprayed cars and a GRP hull before but never aluminium.

Any special additives I need to use? Do I need to buy a "special" marine paint @ 300% markup?

Select to expand quote

FelixdeCat said..
Any advice on painting aluminium spars? I stripped the boom and cleaned it up.

The corrosion barriers have broken down over time and some very minor corrosion has set in.

So rather than just renewing the barriers I was thinking of spraying the boom in 2-pak paint, starting with an epoxy primer. I have sprayed cars and a GRP hull before but never aluminium.

Any special additives I need to use? Do I need to buy a "special" marine paint @ 300% markup?

talk to your local paint supply they will have the procedure for making the paint stay on aluminum ,it ant easy .if you do it with non marine paint and it fails it will cost a hell of a lot more,if you want a professional finish u will need to use professional paint and procedures. and equipment.

If you want to spray with two pack go and read up at a place like Wattyl. I haven't sprayed aluminium but I think you would start with prep first

wattylindustrial.com.au/documents/pcm/information/I-11 SURFACE PREPARATION Non Ferrous Metal v4.pdf

Then spray a primer on - Epinamel UC230

www.wattylindustrial.com.au/documents/pcm/tds/Epinamel%20UC230.pdf

This is a good primer undercoat - nice and easy to spray and sand. Then go onto a top coat like Poly U 400

www.wattylindustrial.com.au/documents/pcm/tds/Poly%20U400.pdf

or if you don't have the spray breathing gear they have a non isocyanate one - Paracryl

www.wattylindustrial.com.au/documents/pcm/brochures/PolyUBrochure.pdf

Ring up the tech guys

"For Technical enquiries:Ph: 132 101 option 2" and have a chat. Usually keen to talk about interesting things like boats.

I like the Wattyl range. Go to a trade store, talk like you know what you want, wear epoxied clothes and ask for a trade price. Don't stuff them around. Buy 10 litre or 4 litre packs. They should have some sort of cash account for trade. As for spraying - I use a small Bunnings compressor, a Star 770 gun and do it outside far away from anyone. Topcoat is the most deadly so use Paracryl if near houses. Everything up to the final coat is for fun - you can just sand off the runs. If you have sprayed before you should be okay. You don't need marine paints, all of my boats and most of my friends are done in trade paint. The amount of fairing required to get a great paint job is huge so get a nice one instead. It is about 5 times easier to get a 90% job compared to a 100% job.

Once I built the shell of a trimaran. The local sprayer said he could spray in one week of touch ups over our faired undercoat. Then the owner got the best sprayer from Sydney. He made us do 3 months more work on prep. It aint the paint that makes a job look good, its the heartache. It aint worth it for most boats.

cheers

Phil

Alloy painting isn't that hard. Start with a good acid etch (they are usually a green colour) followed by a good industrial two part epoxy, a light sand to enhance mechanical bond and then a two pack paint, brand and colour of your choice.
Cheers

Be mindful when using 2 pac compatible under coat products that you allow ample time for solvents to flash off before 2 pac priming or top coating.

Select to expand quote

Kankama said..
If you want to spray with two pack go and read up at a place like Wattyl. I haven't sprayed aluminium but I think you would start with prep first

wattylindustrial.com.au/documents/pcm/information/I-11 SURFACE PREPARATION Non Ferrous Metal v4.pdf

Then spray a primer on - Epinamel UC230

www.wattylindustrial.com.au/documents/pcm/tds/Epinamel%20UC230.pdf

This is a good primer undercoat - nice and easy to spray and sand. Then go onto a top coat like Poly U 400

www.wattylindustrial.com.au/documents/pcm/tds/Poly%20U400.pdf

or if you don't have the spray breathing gear they have a non isocyanate one - Paracryl

www.wattylindustrial.com.au/documents/pcm/brochures/PolyUBrochure.pdf

Ring up the tech guys

"For Technical enquiries:Ph: 132 101 option 2" and have a chat. Usually keen to talk about interesting things like boats.

I like the Wattyl range. Go to a trade store, talk like you know what you want, wear epoxied clothes and ask for a trade price. Don't stuff them around. Buy 10 litre or 4 litre packs. They should have some sort of cash account for trade. As for spraying - I use a small Bunnings compressor, a Star 770 gun and do it outside far away from anyone. Topcoat is the most deadly so use Paracryl if near houses. Everything up to the final coat is for fun - you can just sand off the runs. If you have sprayed before you should be okay. You don't need marine paints, all of my boats and most of my friends are done in trade paint. The amount of fairing required to get a great paint job is huge so get a nice one instead. It is about 5 times easier to get a 90% job compared to a 100% job.

Once I built the shell of a trimaran. The local sprayer said he could spray in one week of touch ups over our faired undercoat. Then the owner got the best sprayer from Sydney. He made us do 3 months more work on prep. It aint the paint that makes a job look good, its the heartache. It aint worth it for most boats.

cheers

Phil

i agree with all of the above except use pr 250 as prime then the uc230 as undercoat dont try and sand the pr250 its very hard we always chemically bond paint with aprox 2 hour window beetween the pr 250 and the uc230

Well the crash supplies place said 2 pak epoxy would be all I need to start so I used the leftovers I aready had. Epotec 408

He said all I need to use after that is a 2pak paint if the colour is not metallic so I won't need to do a clear coat

Now the most important question..... WHAT COLOUR???

White or should I do it the same colour as the canvas dodger that's coming? (Tan)

Does a mast and boom matching the dodger look good or not????