Undercoat and general rust prevention product recommendations

Hi Everyone,

(Apologies if i have posted this topic under the wrong forum section, this is my first post on the forum)

So after buying a puma project at the beginning of the year, I have only recently started the restoration of it to get it back on the road (I will post a separate thread later with progress updates).

I have bought a new rear beam as mine was too rotten and once I have removed all of the surface rust on this I want to coat it in a good paint/rust preventer. Does anyone have any decent recommendations? I've seen Por15 has good reviews amongst classic car restorers but open to other alternatives should people have them

Also looking for recommendations on undercoats for once we have removed all underside rust and done any welding needed

Thanks in advance
Dan

I use Bilt Hamber Hydrate 80 - Quick search but may be cheaper else where :- https://bilthamber.com/product/hydrate-80/

This is the actual bottle I have (amongst other bilt hamber products) :- https://www.amazon.co.uk/Bilt-Hamber-Hydrate-80-500ml/dp/B00672US20

I did my Puma back in the day (10+ years ago) and I still have well over half left of the 500ml bottle I bought. I splashed loads on the crashed Ka I bought in August on the damaged/torn quarter panel as soon as I got it home. I'd recommend giving it a couple of coats as it's pretty quick drying and goes a long way so plenty of use out of even a small bottle, and it lasts a long time as you can tell by me still having a 10+ year old bottle left :lol:

They have plenty of products to choose from if you fancy something different depending on your needs.

I tend to go for whatever's at the cheap shop to be honest and substitute quality for quantity. I've got 3-4 coats zinc primer (Zinc 182 I think) on my rear beam which was sand blasted before painting. Then 3-4 coats of no-name chassis black on top of that. I had plenty of time to let things dry between coats as I was using another car.

That was a couple of years ago and it's holding up well.

I tend to get under the car once a year and attack any rust with wire wheel then the above treatment although depending on what's in the garage I might use red oxide primer. Again lots of coats.

I have squirted plenty of wax around as well when various bits are off (arch liners, suspension bits, fuel tank) for good measure.

It's a messy PITA but patience pays off. Take some pics as you go so you've got a record of your hard work - might come in handy one day.

I've used Bilt Hamber products on my "nice"Puma,, rust converter, deox gel on larger parts (rear brake backplates etc) and their cavity wax around the inside arches, sills, A posts and all chassis sections, all surface rust was cleaned off then underneath was done with rust converter, then zinc primer, then metal paint, followed with black Waxoyl sprayed underneath, same treatment for the wheel arches. In the "tatty" Thunder, I did the same, but used chain spray inside the sills, arches and underneath, 3 large cans for £10, so was cheap compared to the proper cavity wax, it doesn't wash off easily, I used it on a classic Mini rear subframe and it didn't go rusty in the 5 years I owned the car.
I have used Por 15 in the past, it's excellent, but you need to follow the instructions very carefully, a rear axle I did 10 years ago, still looks good.
My objective with my "nice" Puma was to do it properly as I intend keeping the car for many years, whilst the Thunder I just wanted to stop the worst of it, so when I come to sell it, it'll still be solid, but it's had loads of welding previously and has rusty arches, unlike the "nice" one.