Anti Rust Products

[Donald Ross]

Hello

I have owned my morris minor for almost 3 years now and in that time its fair to say i have had a battle with preventing rust.

I have tried a massive range of anti rust paints and just cant seem to find one which will last any length of time especially on the drivers side sill.

The car is dry stored and never out in the rain so at least that is half the battle but still finding it hard to find anti rust coatings which last.

I have even done my own salt water test on a few products to compare them.

So far i have found that both bilt hamber wax+zink coating and international yacht aluminium primer with enamel top coat seem to be fairly good.

Still cant find a good stone chip for the wheel arches though.

I currently am using the aluminium primer (which acts as a anode) on the drivers sill and it looks set to last about 2 years at the most which is 3 times longer than anything else i have used but still not great.

Has anyone got any advice on which anti rust products are best?

Thanks
Doanld

[philthehill]

Currently I use FERTAN and I find it very good and it does what it says on the container.
Previously I used International Paints two pack self etch primer until it was withdrawn and that product was very good as a etch base paint and rust eliminator.

[jagnut66]

Hi,
I use a combination of Dinitrol Converust and Isopon Zinc 182 primer (links below so people know what I'm referring to), along with waxoil / waxoil based underbody protection.
They seem to work quite well (touching wood of course, as rust is the common enemy of us all), not perhaps as specialised as the products listed in the posts above but they do for me.
Hopefully quite a few will respond to this post, as it is always useful to know what's out there and to hear peoples experiences of them, good or bad.
Best wishes,
Mike.

https://www.ebay.co.uk/itm/DINITROL-RC9 ... 1438.l2649

https://www.ebay.co.uk/itm/U-POL-DAVIDS ... 2749.l2649

[jagnut66]

Links to Philthehill's 'FERTAN':

https://www.ebay.co.uk/itm/Fertan-Rust- ... Sw6w1co1UD
https://www.ebay.co.uk/itm/Fertan-Rust- ... Swk~ZaBFd2
https://www.ebay.co.uk/itm/Fertan-Rust- ... xy9X5TXk8G

And I think this is the 'International Yacht Primer' referred to by Donald Ross:

https://www.ebay.co.uk/itm/Primary-Yach ... SwbF1aKjuw

Though please correct me if I'm wrong with any of the links above.
Best wishes,
Mike.

[Donald Ross]

Yes that is the yacht primer i was referring to jagnut66. It seems to be better than anything else i have used and acts in a similar way that zink protection does but which is better im not sure. Seems to last fairly well though.

I must also however add that the bilt hamber electrox zink spray together with the bilt hamber underbody wax is also a good combination.

I have used the aluminium flake yacht primer along with the international enamel top coat and they seem to work well together although still probably wont last any more than a few years.

Will be interesting to hear from you all what you all use to protect you minor.

Donald

[philthehill]

The FERTAN links above are correct. I only purchase the 250ml spray container in the last FERTAN link as it does go a long way.

The car has always been sprayed inside the chassis legs/areas you cannot reach to paint with paraffin and waste oil since new and it has kept the rust at bay.

[ManyMinors]

As Phil says, spraying waste oil was a common (and free!) rust preventative many years ago but should never be used now as the fumes are highly toxic. A great many products are available along the lines of waxoyl preventatives, my own favorite being Supertrol. This used to be available in 5L cans but now seems only to be sold in aerosols. A good product which I have used with success for many years.
As an antirust primer on cleaned-up bare metal I have found nothing to beat Bondaprimer which is now marketed as "Bonda Rust Primer + Zinc" and is available via the internet etc. I don't see either of these products in the shops anymore and both take a little searching for. Worthwhile though and have kept my classic cars rust-free for long periods.
I found that the primer in aerosols was a waste of money. The paint was much too thin and didn't cover. Much better to brush on 2 good coats as instructions and then overpaint to choice for good lasting protection.

[Donald Ross]

Hello Again

Here is a anti rust update.

Turns out that the bilt hamber zink spray, top coated with the bilt hamber underbody wax or international enamel are the best combination i can find so far.

I am considering trying bonda primer as have heard good reviews of it, Does anyone have any experience of bonda primer.

I was thinking of possibly top coating with the original cellulose body paint to make it as it was when it left the factory. How does the cellulose bodywork paint stand up to being on the underside?

Thanks and stay safe
Donald

[Bumpy]

Hi Donald
I come to this topic a bit late as I have only recently bought my minor.

In order for iron to rust it requires water/moisture for the chemical reaction to take place. It’s odd that your car doesn’t go out in the rain and is dry stored, so you need to determine where the moisture is coming from.

My first guess would be that it’s evaporating from the floor or internal walls of the ‘dry’ store. Can you describe the construction of this storage area?

It would be nice to get to the bottom of this.

[Bumpy]

Just so we all understand what is happening. Rust is formed by the reaction between oxygen and iron with water as a catalyst.

Remove any one of those and the rusting stops dead.

We cant remove the iron as that’s our Moggys, but we can try to exclude the oxygen and moisture from the surface. This is the primary job of rust preventers and paints - to provide a barrier.

Unfortunately none of these products are 100% efficient and there is an infinite amount of oxygen available should the barrier become pervious - it’s one fifth of the air that we breathe.

So we are left to tackle the problem of moisture. This I hope we can address.

[Donald Ross]

Hello bumpy.

My car is stored in a concrete sectional garage which is not great in preventing condensation. Since I posted the other posts say for the last 3 months, I have now got 2 tube heaters under the can and have insulated the door and that seems to have stopped the condensation which is good.

It now does not rust like previously although I may do some more insulating in the future.

My main thought is whether bonda primer and original cellulose paint is a good idea for the underside or not?

[Bumpy]

Hi Donald
Glad things have improved. I will go on to elaborate on my rust theories in further postings and some of the stuff may be relevant to you.

Meantime let me say I am no World expert, but have had a life in Science and picked up stuff.

You seem to be torn between finishing your car underneath as it is on the top side (ie. primer and paint) vs the underside treatments you can buy such as Waxoyl, Lanolin spray etc. There is no right or wrong but here is my perspective.

Undercoat and painting

This is a fabulous finish and great for show cars and if perfect will certainly hold back the rust bug, but if you are starting with a car that is already about 50 years old underneath it will be very expensive and time consuming to achieve that perfect unblemished finish. The finish is also relatively fragile and will be damaged if you drive over stones or a resurfaced road with loose chippings. Then the problems begin. Water gets under the paint through the damaged areas and rust creeps out under the paint which eventually will flake and fall off.

Underseal and rust treatments
These give a far less attractive finish but are often viewed only by those people you run over . They can normally be applied after minimal treatment of the underside of the car - remove any big build up of mud and gently wire brush as required. It is very much a DIY job (albeit a bit messy) which can be done piecemeal over a few days or weeks. Some can be brushed on and others sprayed. The finish is not as robust, so avoid things like vigorous pressure washing. One bonus is that many remain pliable and will self heal if hit by stones. With the right product it takes about a day to do all round the car and a couple of hours to refresh annually. The marine community know a thing or two about rust and I like some of their products like lanolin which can be applied easily from a hand spray bottle. The bonus with some of these products is that it keeps nuts and bolt nicely protected and easy to undo when required. Also worth noting is that with most moggys there will be a layer of oil from our engines on the underside. Many of these treatments don't require you to remove this oil but are additive and further enhance its beneficial effect.

Thermal conductivity
Every different surface has a different thermal conductivity. Simplistically this means some surfaces are cold to the touch (high thermal conductivity) and attract condensation, yet others feel less cold. Its about how fast the surface wicks away the heat. Bare metal and to almost the same extent painted metal has a high thermal conductivity. Waxes, oils, rubbers and bitumen have a lower thermal conductivity. Just look at a car parked outside on a winters evening. There will be condensation on the roof, but not on most rubber or undersealed areas.

From this you will see I am squarely in the camp of the underbody oils and waxes.

[Nickol]

Like Phil, I used Fertan for a long time and still do whilst I have some left. However I am more impressed by the BRunox rust converter. Here is a sales link - I assume it is available in GB.

https://www.korrosionsschutz-depot.de/r ... oxy-100-ml

The prolem with Fertan is the washing off and recoating. Sometimes in inaccessibler places this can be difficult to do. With Brunox, it is a single application. I lie. Two coats are recommended but I have found on lightly coated areas, one is enough. It does seem long lasting.

[Bumpy]

Some more ramblings.

There is a great temptation to wrap up the moggy nice and warm in the garage, but please be careful what you use. Many car covers are intended for outdoor use and rightly are impervious to moisture. If you use them indoors any moisture evaporating from the floor will be trapped under the cover and increase the likelihood of condensation on the underside of the car. Ironically if you place heaters directly on the floor this will increase the rate of evaporation of moisture from the floor and COULD worsen the situation. So, get the right cover for your car (I use old duvets) and get the heaters a bit off the actual floor perhaps using bricks so they are warming the air and not the 'damp' floor.

Buy yourself a cheap humidity meter (hygrometer). I think they are only a few quid on e bay, then you will really know what's going on. I will do further topics soon on Relative Humidity and the enemy which is salt.

Here is one example of what I found. I am not giving a personal recommendation
https://www.ebay.co.uk/itm/Humidity-Met ... SwsnBfR7IS

My garage is new with double skinned walls, floor with damp-proof membrane and well ventilated roof. I am very fortunate.
It is never heated except when I am specifically working on the car. I stripped the paint off several iron steel components a couple of months ago. It's too cold to spray them so they have been sitting on the floor since then and thankfully there is not even a slight covering of rust. The other day I was working near the headlights and my breathe was condensing on the glass lenses, so even in relatively ideal situations condensation is still possible.

Fresh air, even in the winter is great at sweeping away moisture laden air.

[Bumpy]

Salt is the enemy

In the UK our thoughtful Local Councils broadcast salt liberally over most of our main roads. This is bad for the underside of our cars on two counts.

Electrolytic decomposition

Its a scientific fact that when an electrolyte is placed between two dissimilar metals then a (small) electric current will flow which results in one of the surfaces eroding away. Salt or sodium chloride creates a perfect electrolyte when in solution. This is why household batteries get soft when they are spent, usually because the outer zinc case has 'dissolved' away. On the underside of cars there are a variety of different metals including seams and welds, so this becomes an issue if a salt solution gets between them. The marine community use sacrificial zinc blocks around their expensive brass propellers which are often replaced annually. We can use zinc based paints or galvanised metals which can help for a while.

Deliquescence

It is tempting to think that if the car is dry then salt solutions cant exist. This is unfortunately wrong. Sodium chloride is a deliquescent material which means it will attract and scavenge any moisture in the air, till it becomes damp and eventually dissolves to form a salt solution. We've all experienced this with damp salt cellars and spilt salt in the kitchen turning to little globules of water. So it could be, on the underside of the car.

It's a two pronged attack - electrolytic decomposition and rust from the free moisture. I would suggest that before we lay up our cars we should gently 'pressure' wash them on the underside or even take then for a ride after a heavy downpour to rinse off the underside. Fresh water is less harmful that salty water.

[Donald Ross]

Hi bumpy.

That is very interesting information you have provided, thank you.

My garage does have a damp proof membrane, was only built 3 years ago, so this will help.

The two 120 watt tube heaters are on there own stands about 2 inches off the floor and seem to work well. Before I purchased them I discovered the car very damp underneath but since the heaters it is completely dry.

I also have started putting a old sheet over the top half of the car and this seems to help.

[Bumpy]

Hi Donald

Glad some of this stuff is useful. Its just me rambling, but if it helps just one other person then its worth it. Just off to watch a bit of football then later may tackle the challenge of explaining Percentage Relative Humidity (RH)

[Myrtles Man]

Certainly a very cogent piece of reasoning, none of which I would disagree with. However, in my own case, I have found that a permanently switched on de-humidifier in the garage keeps all my precious stuff dry and consequently rust-free The alarming quantities of water that I daily remove from the de-humidifier collection tank (perfect for car radiators, steam irons, battery topping-up etc etc) remind me how much better it is to have it in a container rather than being held in the air that surrounds everything that's in the garage!

[JOWETTJAVELIN]

To add to the above, hosing off any vehicle which has been driven on gritted roads is essential for longevity. A real difference can be made to prolonging the life of the car if this is done monthly. What I do is hose all the underside and under the wheelarches, wash the top of the car as normal, by which time the dirt underneath has softened, then go around underneath with a stiff household brush like you use with a dustpan. Then once the dirt has been loosened by the brush, hose it all off. You would be amazed at what is rinsed off even when the car is regularly cleaned in this manner.

Secondly, the gap between the front wing and the inner wing at the A post where the wing bolts on should be covered over with Denso tape to prevent water, salt solution and mud from entering and causing the wing rot which is a great problem on Minors. Preferably the wing should be removed and the area revealed cleaned and treated first.

Lastly, I am sure someone has done it before and might be able to help, but this year I intend to investigate fitting wheel arch liners to the front wings. This will preserve the area around the headlamps and the headlamp bowls, another rust trap, but again corrosion here can be avoided if regular cleaning using the above method is habitual.

[Donald Ross]

Yes i agree.

I never drive my car when the roads have been gritted and only do a few hundred miles a year anyway so dirt is not as bad as it could be.

You have put it in my mind though so hopefully on Tuesday i am going to give the car a good wash and brush down as it has been a while since i last gave it a wash ( only done 50 miles in the last 4 months).

I have owned the car for 2 and a half years now and it came freshly painted with underseal but i am not a big fan of it as it tends to flake and rusts under it. The photo below shows the underside front with the heater to stop frost and help prevent condensation. The light brown coloured paint at both the left and right hand sides is the bilt hamber zink spray over coated with bilt hamber wax, this seems to be lasting better than anything else i have used to date.

I did a experiment about a year ago in salt water with different paints and the two best were the bilt hamber and international aluminium yacht primer. The aluminium acts as a sacrificial metal and protects the steel. I did use this on the drivers sill but soon found bilt hamber to be better.

In saying all this there are parts of the car which had the old red lead paint, and these areas are like new, by far the best paint which is why i thought the bonda primer may be a good modern day alternitave.

Also just to note, the car is wax injected also with bilt hamber wax. Also i have dehumidifiers dotted around the underside and inside of the car. They tend to collect about 1 ltr of water each in a 2 month period at this time of year.

We will see.
Donald