Undersealing/rustproofing

Hi all!

I've got the lovely job of painting the bottom of the mgb and half of the midget soon which Is not going to be a nice job :L but got be be done! Both are sound underneath but previous under seal is flaking in places and surface rust developing.

Just wondering what others use as many have strong opinions on whats best

Previously on (half) of the midget I rubbed down any rust patches to bare metal and wire brushed the rest, then used rust buster products www.rust.co.uk , firstly the rust converter then their epoxy mastic paint. it appears to have a good name and is holding up well so far. However was horrible to apply as it ran everywhere and stains! Plus it stinks and took ages!

I've got some waxoyl underbody seal that I was thinking of using, some say its good, some not?

Just fishing to see how everyone's does this job? What's worked worked and been the best to put on? Plus what holds up the best? I've heard of some trapping moisture underneath and causing havoc by rusting underneath which obviously need to be avoided!

I like the rust buster products and have some left, plus the waxoyl under bosy seal, but thought it would be worth seeing what else is out there and one would recommend!

Dynax S50 is amazing stuff.
They now do a clear one too for places you don't want to coat in rubbery brown gloop.

Thanks! just had a look and looks good, plus isn't too expensive either!

May look into getting some s50 and possiblly the UB too for wheel arches?

I see opie oils sell it and have 20% at the mo which is a bonus!

Cheers!

this is the underside of my Sunbeam Lotus coated in the clear Bilt hamber UC which comes in a decent size spray can with nozzles. i used 2 large cans to do the full underside, it sets clear if you dont spray too much on in one go

It's the S50 you want for ultimate protection, but it is a very dark brown when it dries.
http://www.bilthamber.com/cavity-waxes/dynax-s50

The UB gives more like a traditional underseal finish (I think).

The UC is a very thin clear film which can be removed fairly easily. Dynax suggest you can use it on bits just for the winter for example. I've got some on some underbonnet aluminium parts which were going "furry".

I've always bought direct from the BH website as I've never found anywhere cheaper. Their prices include VAT which most don't until you get to the final checkout...

Just to say that looks lovely. My TR6 underneath looked like that at one time too. It's all covered in dirt now but still rock solid after 10 years of year round use.

wow, this stuff looks the nuts. Will be ordering some this weekend for application to the the Lancer Turbo.

any chance of some more pics of the Lotus Sunbeam 200plus?......don't tease me with a little underside snippet mate....it's just not enough...

Somewhat O/T, but before I had the car painted last time (1988) I thought long and hard and used stone chip paint underneath. Not concours, but it certainly has stopped the car going rusty underneath.

If there's exsisting Waxoyl, what's the best stuff to remove it with?. Brake cleaner or something solvent based?.

Will I need to treat the areas before applying anything else?.

Waxoyl is white spirit based so that gets it off.
I've also used a hair dryer and a scraper before.

Bilt Hamber is great but I'd only use it in cavities.
On my exposed panels I've used POR15 Chassis coat black.
It dries as hard as nails, and doesn't seem to be affected by anything.
As I'm lazy it means I don't need to check it or retreat it.