This is just information I found out from an enquiry to Dulux about using non-proprietary solvents for thinning and cleaning up of Dulux Metalshield paints. I'm not asking anyone here any questions - I'm just passing on handy info. Hardly entertaining but might be useful.

For painting metal, I have normally used Wattyl Killrust. It does the job as far as I'm concerned. One advantage I've noticed is that other metal paints like white Knight and Dulux Metalshield get into bother with the thinners - all sorts of proprietary concoctions. Killrust just uses turps for clean-up and for thinning.

However, I wanted a pot of colour Killrust doesn't have. Dulux Metalshield had it - 'Tractor Blue'. So I got sucked in.

1. Metalshield Epoxy enamel and Premium topcoat use turps for brush thinners. Save yourself some money. Use generic turps.
Ok, so the Metalshield colour topcoats are alkyd enamels that come in two grades - 'Premium' (a silicon alkyd enamel, and more UV resistant) and 'Epoxy Enamel'. Both recommend using 'Metalshield Brush Thinner' for thinning and cleaning. Uh oh, that's $16.50 for a litre. However, the MSDS says that the composition of this product is 'Mineral Turpentine 100%' (but they don't tell you that on the tin). I asked the Dulux technical info, "so, is it alright then to use 100% Mineral Turpentine as a substitute?", just in case there was some trick to it. But their answer was "that's fine, just make sure it's 100% mineral turps.". So, off to the hardware, get a 4L bottle of Diggers turps for $12.50 - that's five times cheaper, for more or less the same thing. I say 'more or less the same thing' because of what is covered in the next paragraph here (which you can skip, if you didn't like Chemistry 101).

First, just as an aside, the hardware paint fellow said "ah, yes, mineral turpentine, but look at the label on the Digger's bottle, it says in the fine print 'turpentine substitute'.". Well, it turns out that yes, mineral turpentine is indeed a substitute for natural turpentine, an expensive and exotic distilled tree resin. So this is not an issue, at least for brush cleaning. The only niggling possibility is that, according to Wikipedia, there are at least three grades of mineral turpentine (aka white spirit, aka turpentine substitute), ranging from pure naptha (like Shellite) to heavier oilier types, of which the Diggers type has a good dash. Whoever contributed to the WP text has added "Turpentine substitute can be used for general cleaning but is not recommended for paint thinning as it may adversely affect drying times due to the less volatile components". What they are meaning is that, with Diggers turps for example (looking at the Diggers MSDS), it is a mixture mainly of light aromatic solvent naphtha (CAS 64742-95-6), (almost like Shellite), and hydrodesulphurized heavy naphtha (CAS 64742-82-1). Since Dulux don't say what their mineral turpentine 'Brush Thinner' consists of exactly, it’s hard to know their proportions of light to heavy naphtha. But when you look back at the ingredients for the actual paints, the 'Epoxy Enamel' uses mainly light aromatic naphtha (CAS 64742-95-6), and 'Premium' uses mainly Stoddard's solvent (8052-41-3), which is close to hydrodesulphurized heavy naphtha. It all comes around in a full circle, there's nothing too odd in it all, and considering that both topcoats use the same 'Brush Thinner', and the Dulux tech say "'mineral turpentine' is fine", there's a good bet that not only can you clean brushes with Digger's Turps, you can use it as a thinner too. If it takes too long to dry, then buy the Dulux version of mineral turps, i.e 'Metalshield Brush Thinner'. But bottom line, Diggers turps will clean your brushes, and there's a very good chance it is quite alright as a thinner too.

2. Metalshield All-surface Primer can use acetone for cleanup - so save yourself money, use generic acetone.
This one is much simpler. I asked Dulux about the thinners recommended for their Metalshield All-surface Primer. On the tin, it says to use 'Dulux Urethane Thinner'. If you go to Bunnings, they won't have it, because, as the Dulux tech people told me, Bunnings don't have the dangerous goods handling requirements for it, so only Dulux Trade stocks it. So at Bunnings they'll have all sorts of theories what you should use (I suspected I was hearing BS, that's why I dug into all of this). The real story is (but it's not written on the tin!) you can use acetone or the urethane thinner. This is both written on the detailed product technical data sheet, http://www.duluxprotectivecoatings.c...0-%20LI014.pdf, and was confirmed verbally by Dulux tech. One other thing, I asked whether xylene can be used as a thinner instead of acetone (since it is a component of the primer too) but Dulux said "xylene thinner may cause the product to fall apart". So stick to acetone. Incidentally, Dulux all-surface primer is a zinc phosphate etch primer, and can be used under all alkyd base topcoats - so that includes Killrust if you like, because that's an alkyd resin enamel too.

HTH


Some people like references:
Metalshield Premium MSDS: https://go.lupinsys.com/duluxgroup/h...AT-AUS_GHS.pdf
Metalshield Epoxy Enamel MSDS: https://go.lupinsys.com/duluxgroup/h...SS-AUS_GHS.pdf
Metalshield All Surface Primer MSDS: https://go.lupinsys.com/duluxgroup/h...EY-AUS_GHS.pdf
Metalshield Premium technical data sheet: http://www.duluxprotectivecoatings.c...t-%20LI011.pdf
Metalshield All surface Primer technical data sheet: http://www.duluxprotectivecoatings.c...0-%20LI014.pdf
Diggers Mineral Turpentine MSDS: http://www.recochem.com.au/files/dow...pentine_v8.pdf


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