CarRust.co.uk review: the free rust handbook every classic owner should have bookmarked

Table of Contents

• Declaring an interest
• What you get
• The two pages everyone lands on
• The pages a classic owner will actually use
• The best page on the site
• The tool guides
• Where it needs a lick of paint
• Verdict

Rust is the one subject every club in the directory has in common. Whether you run a Riley or a Rover 800, the sills go the same way, and the conversation at club night ends up in the same place: what do I put on it, and will it work. We have a sister site built to answer exactly that question, and after a proper afternoon with it we thought it was time to say what it is actually like.

Declaring an interest

Let us get the awkward bit out of the way first. CarRust.co.uk comes out of the same office as this site. The restorers directory it used to carry now lives here, in our restorers section, and the two sites link to each other all over the place. So this is not a review by a stranger. It is a tour by someone who knows where the light switches are. We have tried to be straight about the rooms that need decorating, and you can judge the rest for yourself.

What you get

The site calls itself The Car Rust Handbook, and that is about right. It went live in March 2025 and now runs to nearly forty pages and over seventy thousand words. All of it is free and there is nothing to sign up to. It is organised the way a sensible person thinks about rust: what it is, how to treat it, how to stop it coming back, what to buy, and which tools you need to do the job at home.

The fundamentals page explains the chemistry without turning into a lecture, then gets to the bit that matters: why British cars rust more. No spot in Britain is more than seventy miles from the sea, the roads get salted before the frost arrives rather than after it, and the weather is rarely cold enough to stop the reaction or dry enough to pause it. If you have ever wondered why your car rots faster than the identical one your cousin keeps in Arizona, the answer is on that page.

The two pages everyone lands on

Two pages do most of the heavy lifting, and they are the ones you will find if you type "best rust converter" or "best rust remover" into Google at eleven o'clock at night with a brush in your hand.

The rust converters guide ranks six products and gives each a price per hundred millilitres, which is the only honest way to compare a £19 aerosol with a £42 litre. Jenolite's spray comes out on top, Neutrarust 661 and Rustbuster Fe-123 sit just behind it, and the Hammerite Kurust you can buy in any Halfords props up the table. There is a comparison chart, a section on how the chemistry works, and a long list of the mistakes people make, which is the part worth reading twice. A converter is not something you paint on once and forget, a film of oil you cannot see will stop it working, and nothing in a tin fixes a hole.

The rust removers guide does the same job for the soak-it-in-a-bucket end of the market. It sorts the products by how they work, so acids, chelating agents and the electrolysis crowd each get explained before anything is ranked, and you come away understanding why Evapo-Rust is slow but safe and why Bilt Hamber's Deox-C concentrate works out at about a pound a litre once it is diluted.

The pages a classic owner will actually use

The site covers every car on British roads, but a fair chunk of it was written with ours in mind.

The classic car rust prevention guide has a table of where British marques rot, and it is the sort of thing to read before you buy rather than after. Jaguar sills, arches and bulkheads. MGB sills, spring hangers and battery trays. Triumph outriggers and boot floors. Mini A-panels and rear subframes. Series Land Rovers, where the aluminium body and the steel frame slowly eat each other. The same page makes the case for cavity wax over rubberised underseal on anything old, on the sound basis that underseal hides the structure from you and from the next MOT tester. It also recommends ACF-50 for Lucas electrics, which anyone who has owned a British car will nod at, and tells you a desiccant dehumidifier beats a refrigerant one in an unheated British garage.

The storage guide is split into a fortnight, a few months and a whole winter, with a checklist for each and a section on bringing the car back into service afterwards, which is the bit most people get wrong. It will not let you put a non-breathable cover on a car in a damp garage, and it is right.

The scale rust page has a short section on what the MOT tester is actually looking for: corrosion within thirty centimetres of a prescribed area, filler being no good on its own for anything structural, and mesh and filler being fine only on a panel that does not hold the car together. That is more use than most forum threads on the subject.

The best page on the site

The newest guide is also the best one, and it tells you where the site is heading. The engine rust guide, updated this month, reads like it was written by someone who has had a manifold stud snap on them.

It starts by sorting engine rust into the kind that spoils the look of the bay and the kind that stops the car. Surface rust on a cast iron block is cosmetic and always was. Flaking steel brackets, a weeping core plug and brown coolant are not. It tells you to soak the fasteners the day before rather than the minute before, to use six-point sockets on rusty bolt heads, and never to force a seized manifold stud, because a snapped one turns an afternoon into a head-off job. It tells you to keep rust converter off the block and off anything aluminium, to use a brass brush on alloy, and to mask the engine number before you paint, which is a provenance problem waiting to happen. And it is blunt about two-pack paint: isocyanates, an air-fed mask or nothing, with the HSE guidance linked.

It also points you at enginepaints.com for the factory colour your engine left the works in. That is another site from the same stable, so the same declaration applies.

The tool guides

The tool guides are the newest addition: compressors, MIG welders, plasma cutters and sandblasting cabinets, ranked by owner ratings, each with a buying guide on the specs that matter. The compressor page has a chart of how much air each tool drinks, which is the thing nobody tells you before you buy a small one and try to run a DA sander off it.

Prices move about, so treat any ranking on the site as a shortlist to check rather than a shopping list to follow.

Where it needs a lick of paint

A few things, in fairness.

It is a handbook, not a photo story. Most guides have a couple of pictures and several thousand words, and if what you want is forty photographs of someone welding a sill, you will not find them here.

It is written for every car on British roads, not only the old ones. A classic owner will skim the odd paragraph about galvanised modern shells to get to the bit about box sections with no drain holes.

And the launch pages from spring 2025 are showing their age next to the newer ones. The engine guide and the tool guides are better written and more useful than the pages that launched the site, and the older product pages deserve the same going over.

Verdict

Bookmark it. It costs nothing and it answers the question every club night ends up at. Start with the classic car page to find out where your car rots, read the engine guide before you touch the bay, and keep the converters and removers guides open when you are standing in front of the shelf. And when the job turns out to be bigger than a tin and a brush, our restorers directory has nearly five hundred workshops that will take it off your hands.