Are acrylic paints waterproof

[Dave @W]

In the process of accumulating materials for the just arrived Amati Fifie which will be an RC boat - and of course will get very wet. I did a quick search but my question wasn't answered fully

OK with that statement have looked at the usual Tamiya and Vallejo model paints and these may or may not be waterproof. Their advertising for sure isn't forthcoming. Then there is the ridiculous cost for the amount of paint needed for a boat that is 28 or so inches long. I'll probably consider a craft shop for some of their hobby paint instead. I'm aware that acrylics when dry can be water resistant at a minimum, but are there additives that can fully water proof them? Or should they have a seal coat too? Or just use an oil based paint complete ith oder and very slow drying times,

 

[Martin555.]

In the process of accumulating materials for the just arrived Amati Fifie which will be an RC boat - and of course will get very wet. I did a quick search but my question wasn't answered fully

OK with that statement have looked at the usual Tamiya and Vallejo model paints and these may or may not be waterproof. Their advertising for sure isn't forthcoming. Then there is the ridiculous cost for the amount of paint needed for a boat that is 28 or so inches long. I'll probably consider a craft shop for some of their hobby paint instead. I'm aware that acrylics when dry can be water resistant at a minimum, but are there additives that can fully water proof them? Or should they have a seal coat too? Or just use an oil based paint complete ith oder and very slow drying times,

Hi Dave,

I have made many Rc boats and ships in my time, and over those years I have used Acrylic paint on some of the boats and I have found it best to apply a couple of coats of a mat varnish or gloss varnish if you make a luxury yacht.
In my opinion for a hull it is best to use an Enamel paint.
With Enamel paint you don't have to coat it with varnish unless you have applied some decals then it is best to coat it as the water could get between the decal and wash it off.
The Enamel pain that I use is Humbrol.
If you use an air brush to paint the hull/superstructure I use normal white spirit to thin the paint for spraying instead of the recommended expensive thinners.
Also one small tin-let of Humbrol will go a long way when it is thinned and sprayed.

I hope this answers your question.

 

[Dave @W]

Martin, Thanks for that very good information, Humbrol paints except for some evidently left over stock here in the US is only to be found on ebay - and that's always a shot in the dark on age and quality. I recall many years ago that it was a staple at hobby shops but even those shops have pretty much disappeared. There is a You Tube video that you may find interesting:

.

I do agree with you on using enamel as a hull paint and will have to decide if I want to chance acrylics or just do it with enamel instead of worrying if that boat is going to soak up water, and that Amati Fifie with MDF keel and bulkheads - - is a worry. Oh and I just took a chance on ebay and ordered 2 of the brick matte red for the hull bottom - oh well!!!

 

[Martin555.]

Martin, Thanks for that very good information, Humbrol paints except for some evidently left over stock here in the US is only to be found on ebay - and that's always a shot in the dark on age and quality. I recall many years ago that it was a staple at hobby shops but even those shops have pretty much disappeared. There is a You Tube video that you may find interesting:

.

I do agree with you on using enamel as a hull paint and will have to decide if I want to chance acrylics or just do it with enamel instead of worrying if that boat is going to soak up water, and that Amati Fifie with MDF keel and bulkheads - - is a worry. Oh and I just took a chance on ebay and ordered 2 of the brick matte red for the hull bottom - oh well!!!

Hi Dave,
Another Enamel paint I use is manufactured by Revell.

Re : MDF I give it several coats with polyurethane varnish before i give it a coat of paint.
Also you could always coat the hull in resin before you paint it.

 

[Dave @W]

Hi Dave,
Another Enamel paint I use is manufactured by Revell.

Re : MDF I give it several coats with polyurethane varnish before i give it a coat of paint.
Also you could always coat the hull in resin before you paint it.

Good information again, Martin. I doubt Revell paints are very easy to find in the US outside of a little on AMAZON or ebay. It appears to be a German based product with little distribution here.

I have considered Minwax or similar brand spar varnish as it does seem to be harder then the usual polyurethanes. I have had great luck with both on woodwork projects. I did look at resins as well but so far am a bit confused as there are so many variations and need to dig in further. I've also looked at automotive clear coat as I hav at least an unopened/new half gallon after a car paint project along with about the same amount of epoxy automotive primer - hmmm.

I hope this thread gives some good help to others since there seems to be little on the 'net on the subject

 

[Martin555.]

Good information again, Martin. I doubt Revell paints are very easy to find in the US outside of a little on AMAZON or ebay. It appears to be a German based product with little distribution here.

I have considered Minwax or similar brand spar varnish as it does seem to be harder then the usual polyurethanes. I have had great luck with both on woodwork projects. I did look at resins as well but so far am a bit confused as there are so many variations and need to dig in further. I've also looked at automotive clear coat as I hav at least an unopened/new half gallon after a car paint project along with about the same amount of epoxy automotive primer - hmmm.

I hope this thread gives some good help to others since there seems to be little on the 'net on the subject

Hi Dave,
I normally have to rely on what ever I can find so I have been using ordinary household varnish under the paint and until now I have not had any problems.
Maybe other members could share there experience or secrets in this matter.

 

[Dave @W]

Good Morning (oops, afternoon for you), Martin
I have whatever I noted on the shelf right now except the resin and the Humbrol red I just ordered. I do have a bit of time since I've barely started the ship model. I also had to come up with the radio control system. I'll flip a coin soon though and then post my choice.

As for others posting their way of sealing - seems to be a silence

 

[Clary Peters]

In the process of accumulating materials for the just arrived Amati Fifie which will be an RC boat - and of course will get very wet. I did a quick search but my question wasn't answered fully

OK with that statement have looked at the usual Tamiya and Vallejo model paints and these may or may not be waterproof. Their advertising for sure isn't forthcoming. Then there is the ridiculous cost for the amount of paint needed for a boat that is 28 or so inches long. I'll probably consider a craft shop for some of their hobby paint instead. I'm aware that acrylics when dry can be water resistant at a minimum, but are there additives that can fully water proof them? Or should they have a seal coat too? Or just use an oil based paint complete ith oder and very slow drying times,

I don't know about Vallego but a long time ago we rented the Centennial Pool in Halifax for a regatta. I had a Billings Bankert that was painted with enamels on the exterior but Tamiya acrylic on the inside. after sailing for a bit I noticed a green slick in the boat. Maybe they are ok in lake water but definitely not a pool.

 

[Martin555.]

Good Morning (oops, afternoon for you), Martin
I have whatever I noted on the shelf right now except the resin and the Humbrol red I just ordered. I do have a bit of time since I've barely started the ship model. I also had to come up with the radio control system. I'll flip a coin soon though and then post my choice.

As for others posting their way of sealing - seems to be a silence

Hi Dave,
I cannot guide you regarding RC Transmitters and Receivers as you have different regulations to what we have here in the U.K.
However I can help with installations and other RC related things.
So if you need any help then just give me a shout and I will do my best to help you.

 

[Martin555.]

I don't know about Vallego but a long time ago we rented the Centennial Pool in Halifax for a regatta. I had a Billings Bankert that was painted with enamels on the exterior but Tamiya acrylic on the inside. after sailing for a bit I noticed a green slick in the boat. Maybe they are ok in lake water but definitely not a pool.

Hi Clary Peters,
I think also the chlorine in the pool water did not help.

 

[Dave @W]

Martin & Clary
That radio installation process between the US and UK is the same though suspect that the transmitter frequency and possible use permits may be different. I've purchased a mostly INJORA system tough they supplied me with an off brand ESC which has a Deans plug rather then their usually supplied big Tamiya - another AMAZON 10 dollar order for an adapter. Everything else is on my table ready to go (I think!!) I'll do what I can for setup, Martin and keep you in mind if (when?) I have a glitch

Chlorine is downright nasty stuff. Our local water system here in my town uses way too much - and it has clouded water glasses and is almost unuseable for drinking and cooking - and I itch after a shower like after a dip in a swimming pool

 

[WDO]

Re: are acrylic paints waterproof?
A simple answer is no. They are water based paints that will deteriorate in water or alcohol solutions. You can protect them with a lacquer overcoat. Many use that system for a particular color that is only available in acrylic.

 

[Van]

The acrylic paint (Liquitex, etc) used by artists is a lot cheaper than those sold for model builders. The manufacturer rates them as water resistant, so not waterproof. But, as others say, if topcoating them with a waterproof film works, then artist paints are cheaper and available everywhere. Here's a web site to start with. You can also get info on transparency/opacity, lightfastness, etc. https://www.liquitex.com/us/knowledge/what-is-acrylic-paint/

 

[Dave @W]

The acrylic paint (Liquitex, etc) used by artists is a lot cheaper than those sold for model builders. The manufacturer rates them as water resistant, so not waterproof. But, as others say, if topcoating them with a waterproof film works, then artist paints are cheaper and available everywhere. Here's a web site to start with. You can also get info on transparency/opacity, lightfastness, etc. https://www.liquitex.com/us/knowledge/what-is-acrylic-paint/

I just went to the Liquitex website - very interesting reading. I haven't dug into it very far yet but it does look like a viable alternative for many things in modeling. Thanks for that info

​

 

[blickwer]

The acrylic paint (Liquitex, etc) used by artists is a lot cheaper than those sold for model builders. The manufacturer rates them as water resistant, so not waterproof. But, as others say, if topcoating them with a waterproof film works, then artist paints are cheaper and available everywhere. Here's a web site to start with. You can also get info on transparency/opacity, lightfastness, etc. https://www.liquitex.com/us/knowledge/what-is-acrylic-paint/

In his book Building First Rate Ship Models From Kits, Ben Lankford suggests that the acrylic in model paints is ground finer than the acrylic in artist paints. This creates sharper corners and finer detail. Any truth to this? The book was published by Model Expo. They also make paints.

 

[Uwek]

I don't know about Vallego but a long time ago we rented the Centennial Pool in Halifax for a regatta. I had a Billings Bankert that was painted with enamels on the exterior but Tamiya acrylic on the inside. after sailing for a bit I noticed a green slick in the boat. Maybe they are ok in lake water but definitely not a pool.

Hallo @Clary Peters
we wish you all the BEST and a HAPPY BIRTHDAY

 

[Van]

In his book Building First Rate Ship Models From Kits, Ben Lankford suggests that the acrylic in model paints is ground finer than the acrylic in artist paints. This creates sharper corners and finer detail. Any truth to this? The book was published by Model Expo. They also make paints.

I don't have any technical specs but when using some model paints they feel like they're more finely ground than Liquitex