Cannon lard - what is it and why does your car need it?
If you've ever looked under the underbody of an old car, you've probably seen rusty holes where the metal has worn thin. Corrosion is the main enemy of the body, and you can fight it in different ways. One of the most proven and accessible methods is cannon fat, which car enthusiasts have been using for several decades. But what is this substance, why is it called that and how to use it correctly?
Gun lard is a thick preservative lubricant based on petroleum oils with the addition of thickeners and anti-corrosion additives. It was originally developed to protect artillery pieces (hence the name) from rust during long-term storage. Over time, the composition was adapted for the automotive industry, and now it is actively used to treat hidden cavities of the body, underbody and other vulnerable places.
The main advantage of cannon fat over modern anticorrosion agents is its high adhesion (the ability to firmly adhere to metal) and long period of protection (up to 3–5 years if applied correctly). However, it also has disadvantages: the complexity of application, the need for preliminary surface preparation and the risk of leaks due to overheating. Next, we will analyze everything in detail - from the composition to step-by-step instructions.
Composition of cannon fat: what's inside and how it works
Classic cannon lard consists of three main components:
- 🛢️ Mineral oils (up to 80–90%) is the basis of the composition, creating a protective film on the metal. Typically, industrial oils such as I-20A or I-40A are used.
- 🧪 Thickeners (5–15%) - paraffins, ceresins or soaps, which give the lard a thick consistency and prevent dripping.
- 🛡️ Anti-corrosion additives (1–5%) - corrosion inhibitors (for example, calcium sulfonates), which neutralize oxidative processes.
Some manufacturers add to the composition graphite (to improve heat resistance) or wax (to increase water-repellent properties). It is important to understand that cannon fat doesn't dry out — it remains plastic and sticky, which allows it to “self-heal” in case of minor damage to the film.
For comparison, modern anticorrosion coatings based on bitumen or rubber form a hard coating that can crack over time. Gun lard works on the principle of an “oil bath”: it penetrates microcracks in the metal and displaces moisture, preventing oxidation.
Advantages and disadvantages: is it worth using cannon lard?
Like any anticorrosive agent, cannon lard has its pros and cons. Let's look at them objectively, without embellishment.
| Benefits | Disadvantages |
|---|---|
| 🔹 Long protection period (3-5 years if applied correctly) | ⚠️ Difficult to apply without special equipment (gun, compressor) |
| 🔹 High penetrating ability - fills microcracks and pores | ⚠️ When heated (for example, in the sun in summer), it may leak |
| 🔹 Does not require a perfectly clean surface (unlike bitumen mastics) | ⚠️ Attracts dust and dirt - over time the coating turns black |
| 🔹 Low price compared to professional anticorrosion agents | ⚠️ Difficult to remove when reprocessing (requires solvent) |
| 🔹 Compatible with most paintwork and rubber seals | ⚠️ Not suitable for external surfaces (spoils the appearance) |
Critical nuance: gun lard is not suitable for treating external body panels (hood, fenders, doors), as it does not dry out and remains sticky, attracting dirt. Its main purpose is hidden cavities (sills, side members, arches) and the bottom.
⚠️ Attention: Do not use gun lard on the brakes, exhaust system or suspension! If it gets on brake pads or discs, it can cause slipping, and on a hot muffler it can ignite.
Step-by-step instructions: how to apply cannon lard correctly
Applying gun lard is a labor-intensive process, but if everything is done according to technology, the protection will last for several years. Here are the detailed instructions:
- Preparing the car
Wash the car thoroughly, especially the underbody and wheel arches. Use car shampoo and a brush to remove dirt. Then dry the surfaces
construction hairdryeror leave the car in the sun for 2-3 hours. - Removing rust and old coating
Clean metal from rust
wire brushor sandblaster (if you have access). Remove old gun fat or mastic with a solvent (for example, White spirit or Solvent). - Degreasing
Wipe surfaces degreaser (acetone, antisilicone). This is important, since greasy stains impair the adhesion of lard.
- Applying gun lard
To process hidden cavities (thresholds, side members), use
grease gunwith flexible nozzle. Suitable for the bottom brush with stiff bristles or sprayer (if the lard is heated). Apply a layer 1–2 mm thick, leaving no gaps.Grease gun (or brush)|Compressor (if using a spray gun)|Degreaser (acetone, anti-silicone)|Safety gloves and glasses|Solvent for cleaning tools-->
- Drying
After application, leave the vehicle in a dry place for 12–24 hours. Avoid driving on muddy or wet roads for the first 2-3 days.
If you are treating thresholds or other closed cavities, make them technological holes (8–10 mm in diameter) for gun access. After processing, the holes can be closed rubber plugs or silicone sealant.
Before application, heat a jar of gun lard in warm water (not higher than 50°C) - this will make it more fluid and pass through the gun easier.
Top 5 anticorrosion guns: what to choose in 2026
There are many brands of cannon lard on the market, but not all are equally effective. We tested several popular options and compiled a rating:
| Brand | Features | Average price (5 l) | Rating (out of 5) |
|---|---|---|---|
| VMPAUTO MS-50 | Classic gun lard with the addition of graphite. Holds well on vertical surfaces. | 1 200 ₽ | ⭐⭐⭐⭐⭐ |
| LIQUI MOLY Wachs-Konservierer | German quality, high temperature resistance (up to +120°C). Suitable for processing the bottom and arches. | 2 500 ₽ | ⭐⭐⭐⭐½ |
| Tektil ML (Mobil) | Universal preservative lubricant, compatible with most paintwork. Easy to apply with a spray. | 1 800 ₽ | ⭐⭐⭐⭐ |
| Russian anticorrosive "Pushsalo" | Budget domestic option. Suitable for treating hidden cavities, but may leak in hot weather. | 800 ₽ | ⭐⭐⭐½ |
| CRC Heavy Duty Corrosion Inhibitor | American composition with added wax. Has high water-repellent properties. | 3 000 ₽ | ⭐⭐⭐⭐⭐ |
When choosing, pay attention to temperature range (optimally from –40°C to +100°C) and corrosion inhibitor content. Cheap analogues may contain too much paraffin, which dries out and cracks over time.
⚠️ Attention: Do not buy cannon lard from uncertified stores! Counterfeits are often diluted with diesel fuel or used oil, which negates all protective properties.
Common mistakes when using cannon lard
Even experienced car enthusiasts sometimes make mistakes that reduce the effectiveness of the anticorrosion agent. Here are the most common:
- 🚫 Application on rusty metal without cleaning - lard will not stop corrosion if it has already begun. Remove rust first, then treat rust converter (for example, Tsinkarem).
- 🚫 Using too thin a layer — the optimal thickness is 1–2 mm. A thin coating dries quickly and ceases to protect.
- 🚫 Treatment of wet surfaces — moisture under a layer of grease will accelerate corrosion. Dry the metal before applying!
- 🚫 Ignoring technological holes — without them, lard will not penetrate into hidden cavities (for example, inside thresholds).
- 🚫 Storing an Open Can — cannon fat oxidizes in air. Always close the container tightly.
Another common mistake is mixing gun lard with other anticorrosives (for example, with bitumen mastic). This can lead to delamination of the coating and loss of protective properties. If you decide to change the type of anticorrosive, first completely remove the old coating.
What to do if cannon fat begins to leak?
If in the summer in the sun the lard begins to “cry” (smudges appear), this means that it has heated up above the critical temperature. Solution:
1. Remove excess with a cloth soaked in White spirit.
2. When next processing, choose a compound with higher heat resistance (for example, LIQUI MOLY Wachs-Konservierer).
3. Avoid applying too thick a layer - optimally 1–1.5 mm.
Alternatives to cannon lard: which is better for anticorrosion?
Gun lard is not the only option for corrosion protection. Depending on your budget and objectives, you can consider alternatives:
| Anticorrosive type | Benefits | Disadvantages | Protection period |
|---|---|---|---|
| Bitumen mastic | Hard coating, non-stick, suitable for external surfaces | Cracks over time, difficult to apply into hidden cavities | 2–4 years |
| Movil | Easy to apply, good penetration | Weak mechanical strength, dries quickly | 1–2 years |
| Liquid plastic | Impact resistant coating, suitable for arches and underbody | Expensive, requires professional application | 3–5 years |
| Wax compounds | Eco-friendly, easy to update | Short validity period (6–12 months) | 0.5–1 year |
| Zinc sprays | Active protection (zinc interacts with metal) | Requires a perfectly clean surface, dear | 2–3 years |
If your budget is limited and the car is not new, cannon fat remains one of the most profitable options. For new cars or premium models, it is better to consider liquid plastic or zinc coatings — they are more expensive, but provide more reliable and durable protection.
Gun lard is ideal for treating hidden cavities (sills, side members, doors) and the underbody of old cars. For new cars or external panels, it is better to choose bitumen mastic or liquid plastic.
FAQ: answers to frequently asked questions about cannon lard
Can gun lard be applied over rust?
No, it's pointless! Cannon fat doesn't stop corrosion, but only slows down its distribution. If the metal is already rusty, clean it first wire brush or sandblasting, then process rust converter (for example, Tsinkarem), and only after that apply lard.
How often does cannon fat need to be renewed?
The protection period depends on the operating conditions:
- 🚗 In a dry climate - once every 4-5 years.
- 🌧️ In a humid climate or when driving on salty roads - once every 2-3 years.
- 🏗️ For aggressive use (off-road driving) - annually.
Check the condition of the coating in spring and autumn: if the lard is worn out or dried out, it’s time to renew it.
Is it possible to paint over gun fat?
No, the paint will not stick to the sticky surface of the lard. If you plan to paint (for example, the underbody), completely remove the grease first solvent (White spirit, Solvent), then degrease the surface and only then paint.
What is the difference between cannon lard and grease?
These are completely different compositions!
- 🔧 Cannon fat — a conservation lubricant with anti-corrosion additives, designed for long-term metal protection.
- 🛠️ Solid oil — universal grease for bearings and mechanisms. It does not contain corrosion inhibitors and dries quickly in open air.
There is no point in using grease instead of gun fat - it will not provide long-term protection.
Is it possible to use cannon fat to process a pendant?
No, it's dangerous! Cannon fat can:
- 🔥 Will ignite if it comes into contact with hot parts (for example, brake discs).
- 🛑 Cause rubber bushings and silent blocks to slip.
- 🚗 Attract dirt, which will accelerate the wear of ball joints and steering rods.
For suspension, use special lubricants (for example, LIQUI MOLY LM 50 or Molykote).