Rustproofing Chassis

[myoldjalopy]

I would like to ask what product members use on the underside of the chassis to guard against rust - and why they think it is good.
Many thanks.....

[Peted7202]

Dinitrol. Easy to apply by aerosol and pressure system. Use aerosol tube for inside box sections. Good coverage. Good price if you shop around. Have used it on a number of cars.

[svenedin]

I have used Dinitrol in doors and it seems good but it does not flow well in cold weather.

Stephen

[ManyMinors]

I used to be very happy with "Supertrol" but I understand that the business changed hands and the specification of the product also changed and no longer seemed nearly as good. I now use Bilt Hamber "Dynax" products. The produce a clear spray for inside box sections and a darker material for the underside. Available on the internet. Good coverage and easy to apply. Very pleased with the results.

[King Kenny]

I have just applied a lanolin based product (Lanoguard) to the underside of my Traveller. I had used a similar product that I used to pinch from work. It works well and you don't need much. The small bottle will do a car three or four times. It does smell like a wet sheep for a day or two, but it is kind to the hands.

[bobtail4x4]

but is it any good?
lots of people are pushing lanolin, I cant find any long term tests,

isnt it supposed to be re applied each year?

[King Kenny]

Lanolin works well. It creeps into the seams. It is quick to apply and your car would benefit from re-applying where it is likely to be washed off. It took me 15 minutes to spray my traveller. This is the first time that I have used the commercially available product, but I have used a similar product that I pinched from work where it was used to protect bare steel. That was twenty years ago, I wish I had pinched more.
The stuff that I bought is thicker and a bit expensive (compared to what I paid before), but it goes a long way. Inside the box sections it would last many years and my Traveller has not needed any welding since I first applied it.

[bobtail4x4]

everyone tells me its easy to apply,
and needs doing every year,
as said I cant find any long term or "accelerated" salt type tests?

[svenedin]

I would be interested to hear how lanolin performs over time.

My research has revealed that Lanolin oxidises over time to acidic compounds. This does not sound desirable inside a box section. Of course lanolin is a natural product from sheep's wool and so much less damaging to the environment or to the person applying it than the petrochemical treatments but it does not have the extremely long term stability of the petrochemical products.

The trouble with the thicker layer type underseals is that eventually they lose their adhesion to the metal. Then water gets between the underseal and the metal and is trapped which is worse than no underseal at all!

As one of my interests is clocks and antiques I recall the story of the development of "Renaissance Wax" by the British Museum in the 1950's. This was developed to protect metals. It was known for centuries that waxes could protect metals but the problem was that as the waxes degraded over time they became acidic and damaged the metal. This did not happen with Renaissance Wax which is far too expensive to ever contemplate using to protect a car! Nonetheless the same principle applies, especially in an inaccessible area that may only be treated once and then left for decades. The substance must not degrade and become corrosive in its own right.

Stephen

[michael4]

I use Fluid Filmand have used it for over 20 years on various cars. It gives the impression of never drying and is very good at penetrating seams and joins. I believe it is sheep based, you can tell by the smell.

If ever I have the desire to go under the car (not so often these days) I take an aerosol with me.

[michael4]

duplicate post apols.

[kevin s]

I've used a mix of 1/3 new 10w40 engine oil and 2/3 waxoyl for donkeys years, has kept the rust pretty much at bay on my TR7 which was used every day for many years..

[Bill_qaz]

Did it help the donkeys ears as well as rust proofing the TR7

Sorry couldn't resist

[bobtail4x4]

I think I will go with the thinned down/heated waxoil,
it has a track record, ok perhaps not the best you can buy, but I have a few gallon cans still,

[HARBER07]

The most important thing is to seal both sides of repairs, seams, welds etc wherever possible, but sadly it usually gets forgotten about. By sealed I mean seam sealer, or paint where external, inside and out. This stops moisture encroaching into the bare metal joins where welding has occurred and burned off paint. But it must be applied correctly.

I have repaired vehicles with and without carrying out this process, a the unsealed repairs do not last long at all. The sealed repairs have faired infinitely better, and have not shown any signs of degradation over the last decade despite being used all year round in all weathers.

If this has been carried out you can pretty much protect over the top of this with whatever your personal preference is. The key is to have properly protected joints, rather than covering them with a sticking plaster.

[Dryad]

By sealed I mean seam sealer, or paint where external, inside and out. This stops moisture encroaching into the bare metal joins where welding has occurred and burned off paint. But it must be applied correctly.

Which seam sealer do you recommend?

[HARBER07]

I have used Würth DIchtfix /sealfix before but it’s quite expensive now. It’s a sprayable sealant. There is similar available from other suppliers.

[Bill_qaz]

Just purchased "chassis guard" lanolin oil from buzz weld.
Complete kit with gun, long nozzle for inside box areas. You get one tin of oil and a spare empty can if you want to use a different product. Good value and much cheaper than the heavily advertised other brand lanolin. It also claims to dry quicker.
I chose this because prior to my ownership the car has been treated, you can see areas of tan coloured substance and apparently chassis guard can be sprayed over other treatment without reacting and will penertrate seams and dispel moisture. The plan is to do box sections and inside doors and cavities prior to fitting new carpets.
Who knows how good it is but having read up on it I don't think it can do any harm and should help keep the metal maggots at bay

20251210_151135.jpg (414.27 KiB) Viewed 76642 times

[philthehill]

A regular dose of old oil and paraffin works wonders.

[Bill_qaz]

A regular dose of old oil and paraffin works wonders.

Hopefully Phil, this will be as affective but a bit cleaner to use
I worry that paraffin would dissolve the treatment thats already in there.