Chassis Protection

[billm]

Although not a Renault owner, I am renovating a car and am removing the body off the chassis and am going to blast the chassis to remove all the old paint etc etc.

My question is simple. What should I use to protect the bare chassis once it has been blasted. I understand that Waxoyl or Dinitrol Wax are the best flexible products , for internal box sections, but would you paint a bare chassis with them too ?

I would like the chassis to be finished in black if possible. So should I paint it with a zinc based primer, then a chassis black paint then spray it all with clear Waxoyl ?

or is there a better way ?
thanks

 

[malcolm]

I wouldn't use waxoyl on the outside of the chassis - that stuff never dries and is difficult to wash off when you get covered in it while working underneath. Also it's not all that resistant to spray from the wheels.

The big problem with the Renaults is rust in the seams especially in double thickness areas. I'd start off by getting the outside of the chassis completely clean, then seam seal around all the seams, then a zinc based primer.

For paint system, you'll need something stone chip resistant. There are a couple of options:

My favourite is anti-stone chip primer (comes in shultz canisters) followed by 2 pack colour coat. It's an expensive option, but mud doesn't stick to 2 pack very easilly so the underside is easy to keep clean.

Another option is painting the underside with something like Smoothrite and then undersealing the bits that will be sprayed by the road wheels. I'm not a fan of chassis black - normally it's really thin stuff that flakes off. Beter off with something like smoothrite or tractor paint. Mud sticks to underseal so more of a pain for washing, and the underseal will dry up and need replacing after 15 years where the 2 pack should last longer and only need local repairs.

Inside the chassis members waxoyl or Dinatrol is a good plan. Inject it through holes drilled from underneath at the lowest points of the chassis and these will act as drain holes.

When taking a car apart you'll see where the mud collects. Make design changes or add mud shields to stop if from collecting there after restoration, and waxoyl behind the shield. Mud traps are the worst cause of rot as the mud never dries out.

What car are you working on?

 

[billm]

Hi, thanks for the reply. Very informative. I take your point about the mess Waxoyl will cause under the car, I'd never thought of that.

I have an untouched tin of POR15, would that be any good on the chassis or stick with Smoothrite. I hadn't thought of Smoothrite before as i heard it is brittle and likely to chip ?

The 2-pack solution sounds good, but I havent got all the breathing apparatus that I would need so I'll probably have to go with the smoothrite option. I have been priming all my panels, inside and out, with BONDA primer +zinc which I believe is very good. Should I apply that onto the bare chassis before the smoothrite ?

My car is a 1954 Sunbeam Talbot Alpine, 2-door convertible. Had her for 30 years and now doing a total nut&bolt restoration

Here's my restoration site: http://alpine.letusfixit.co.uk/

 

[malcolm]

Por15 has a very good reputation, but I've never got around to trying it. Probably it will be better than smoothrite which isn't resistant to stone chips and would need to be covered with underseal or similar. I think both claim to be paintable onto bare metal, but I know smoothrite has a much better chance on top of the Bondarust, so I'll guess Por15 is the same.

I love the Alpine, and the website looks like it's going to be very handy for other owners. I've got a '59 MGA I restored in the early '90s. But I hardly use it any more so it might be sold on soon. I used a Bondarust style primer on the chassis and then household gloss on top. It's lasted well, probably as the chassis isn't really really exposed to stone chips. For the underside of the body I used anti-stone chip primer with cellulose top coat on top and again that's worked.

No underseal anywhere on the MGA - it's nasty stuff really, but I did have a big engine oil leak a few years ago which will have seured the future of the transmission tunnel. When underseal starts to harden and peel off it will trap water behind which will rot the body. Wouldn't use it unless I had to.

It's possible to get a filter mask for 2 pack these days, and they appear to be very effective. According to the paint shop some of the professional paint shops use them because they are less cumbersome than air fed masks.

If you need any help with the welding then www.mig-welding.co.uk might be helpful.

 

[billm]

Yes the Alpine is a nice car. I couldnt afford to pay anyone to do the body hence why I'm having to learn to do it myself. And I wanted to save all the details incase anyone else wanted to do their Sunbeam at some stage hence the site.

I've seen your MGA site before I think, it certainly looks familiar. I think it was one of the sites that gave me the inspiration to do my Alpine ! The car looks great, it would be a shame to sell it after all that work.

I'm still some way off working on the chassis so I'll ask about those masks for 2-pack paint when I'm in the paint shop next time. Failing that, I'll use POR15 or Smoothrite over the top of the Bonda primer. Any specific anti stone-chip primer you could recommend for underthe wings ?

thanks for the advice, its been very helpful.

 

[malcolm]

For stone chip primer - I tend to use the stuff that you spray on with a shultz (underseal) gun. It comes in the same 1L canisters as the underbody shultz but is described as "an over-paintable anti-stone chip primer". I've not described it well, but your local motor factors or paint shop will know what I'm talking about if you print this post off and put it under their noses.

 

[Rick Simpson]

Although not a Renault owner, I am renovating a car and am removing the body off the chassis and am going to blast the chassis to remove all the old paint etc etc.

My question is simple. What should I use to protect the bare chassis once it has been blasted. I understand that Waxoyl or Dinitrol Wax are the best flexible products , for internal box sections, but would you paint a bare chassis with them too ?

I would like the chassis to be finished in black if possible. So should I paint it with a zinc based primer, then a chassis black paint then spray it all with clear Waxoyl ?

or is there a better way ?
thanks

Hi there.

If you are going to take the time and trouble of having the metalwork blasted clean, then the best system in the world (without any doubt) is to spray or brush apply a coat of Zinga all over the chassis. It instantly galvanises the metalwork, it has a very high coefficient of distortion and vibration and can be overpainted with any black 2K polyurethane.

This will give a minimum of 20 years protection to your car. Zinga comes in cans (for spraying through a normal spraygun) and also in aerosols.
Zinga has been used in projects in Classic Car magazine and Classic Ford magazine.

Kind regards,

The Corrosion Master