Paint... - UK Vintage Radio Repair and Restoration Discussion Forum

7th May 2014, 4:46 pm

Building a model aircraft (flying) I wanted some paint, thought Humbrol. The shop had normal Humbrol and their acrylic stuff, bought the acrylic, very good paint indeed. I would recomend it for any cabinet touch up.

dseymo1 · 7th May 2014, 6:18 pm

Acrylic paint is available from many craft suppliers, and is indeed good stuff. Even works well on leather - I refurbished my steering wheel with some.

Boom · 9th May 2014, 8:48 pm

Acrylic every time. No need to go to the expense of Humbrol you can get boxes of artists tubes of Acrylics in Poundland.

It fills small holes in Rexine perfectly as well as being dead easy to colour mix/match.

Alistair D · 9th May 2014, 9:42 pm

I use Humbrol acrylic for redoing the lettering on AOs etc. Great results too once you work out how to avoid getting the paint where you don't want it.

Al

Bazz4CQJ · 10th May 2014, 7:25 pm

Can someone be more specific about how the acrylic compares with the traditional Humbrol gloss enamel? The latter is a fairly thick, very glossy paint and quite tough. I'm guessing that the acrylic is thinner and flatter?

B

brenellic2000 · 11th May 2014, 10:22 am

The basic difference is that traditional enamel was oil based and thus contains 'volatile compounds' (VOCs) potentially falling foul of the H & S men while acrylics are generally water based. The finish depends much on preparation and brand. It is a case of 'suck it (metaphorically of course!) and see'. But yes, enamels generally are far superior in body and durability.

kalee20 · 12th May 2014, 1:11 pm

I'm not certain about this, but isn't it cellulose-based paints that are full of solvents? And the VOC's contribute to atmospheric pollution, rather than having H & S consequences. The paint hardens by evaporation of the solvents. So although you get a good durable finish, it can be swilled off by cellulose thinners.

Oil-based paints do have solvents, but not so much. And they harden by the irreversible oxidation of the oil. The cured finish is certainly durable.

Acrylics are water dispersed, but apart from the wather evaporation,there is a chemical reaction which takes place too - you can't wash it off (or clean your brush) with water once it has dried.

Feel free to contradict me, anyone with better knowledge!

brenellic2000 · 13th May 2014, 4:05 pm

Yes, but...

As you say, traditional oil based paints use boiled linseed oil with pigments which, being a vegetable oil is 100% natural; this dries naturally through oxidisation (hence use of a single-boiled oil). However, very very few so-called 'oil based' paints today use linseed oil in volume and instead use processed hydrocarbon oils or mixes with a volatile drying agent, the VOC factor. These are/can be noxious.

Cellulose paints use the most volatile solvents which act a drying agent in the sense that the 'liquid cellulose' melds into a solid form after evaporation.

The VOC issue is overplayed, except in large industrial applications where it can be captured - hence water based acrylics for car-paint - but to the home user, we exhale far more 'damaging' CO2 and flatulate more methane in day than in a life time's use of domestic paint. Don't ask for the figures

Whereas we can control VOC from a tin of paint by putting a lid on it, we need self-controlled abstinence to control exponentional C02 and methane from over-population! But that's very much off topic!

7th May 2014, 4:46 pm	#1
Guest Guest Posts: n/a	Paint... Building a model aircraft (flying) I wanted some paint, thought Humbrol. The shop had normal Humbrol and their acrylic stuff, bought the acrylic, very good paint indeed. I would recomend it for any cabinet touch up.

7th May 2014, 6:18 pm	#2
dseymo1 Retired Dormant Member Join Date: Dec 2007 Location: Shropshire, UK. Posts: 3,051	Re: Paint... Acrylic paint is available from many craft suppliers, and is indeed good stuff. Even works well on leather - I refurbished my steering wheel with some.

9th May 2014, 8:48 pm	#3
Boom Retired Dormant Member Join Date: Jan 2007 Location: Westbury, Wiltshire, UK. Posts: 2,451	Re: Paint... Acrylic every time. No need to go to the expense of Humbrol you can get boxes of artists tubes of Acrylics in Poundland. It fills small holes in Rexine perfectly as well as being dead easy to colour mix/match.

9th May 2014, 9:42 pm	#4
Alistair D Nonode Join Date: Jan 2010 Location: Edinburgh, UK. Posts: 2,008	Re: Paint... I use Humbrol acrylic for redoing the lettering on AOs etc. Great results too once you work out how to avoid getting the paint where you don't want it. Al __________________ I won't tell you how I discovered that.

10th May 2014, 7:25 pm	#5
Bazz4CQJ Dekatron Join Date: Apr 2009 Location: Oxfordshire, UK. Posts: 4,935	Re: Paint... Can someone be more specific about how the acrylic compares with the traditional Humbrol gloss enamel? The latter is a fairly thick, very glossy paint and quite tough. I'm guessing that the acrylic is thinner and flatter? B

11th May 2014, 10:22 am	#6
brenellic2000 Octode Join Date: Aug 2006 Location: Rye, East Sussex, UK. Posts: 1,647	Re: Paint... The basic difference is that traditional enamel was oil based and thus contains 'volatile compounds' (VOCs) potentially falling foul of the H & S men while acrylics are generally water based. The finish depends much on preparation and brand. It is a case of 'suck it (metaphorically of course!) and see'. But yes, enamels generally are far superior in body and durability.

12th May 2014, 1:11 pm	#7
kalee20 Dekatron Join Date: Feb 2007 Location: Lynton, N. Devon, UK. Posts: 7,087	Re: Paint... I'm not certain about this, but isn't it cellulose-based paints that are full of solvents? And the VOC's contribute to atmospheric pollution, rather than having H & S consequences. The paint hardens by evaporation of the solvents. So although you get a good durable finish, it can be swilled off by cellulose thinners. Oil-based paints do have solvents, but not so much. And they harden by the irreversible oxidation of the oil. The cured finish is certainly durable. Acrylics are water dispersed, but apart from the wather evaporation,there is a chemical reaction which takes place too - you can't wash it off (or clean your brush) with water once it has dried. Feel free to contradict me, anyone with better knowledge!

13th May 2014, 4:05 pm	#8
brenellic2000 Octode Join Date: Aug 2006 Location: Rye, East Sussex, UK. Posts: 1,647	Re: Paint... Yes, but... As you say, traditional oil based paints use boiled linseed oil with pigments which, being a vegetable oil is 100% natural; this dries naturally through oxidisation (hence use of a single-boiled oil). However, very very few so-called 'oil based' paints today use linseed oil in volume and instead use processed hydrocarbon oils or mixes with a volatile drying agent, the VOC factor. These are/can be noxious. Cellulose paints use the most volatile solvents which act a drying agent in the sense that the 'liquid cellulose' melds into a solid form after evaporation. The VOC issue is overplayed, except in large industrial applications where it can be captured - hence water based acrylics for car-paint - but to the home user, we exhale far more 'damaging' CO2 and flatulate more methane in day than in a life time's use of domestic paint. Don't ask for the figures Whereas we can control VOC from a tin of paint by putting a lid on it, we need self-controlled abstinence to control exponentional C02 and methane from over-population! But that's very much off topic!