11 replies to this topic

[rowanxx]

Just about to start work repairing rust on my Mini, and was wondering what sort of primer to use as I go along. Thinking once I have removed rust/ welded in new panels they may go rusty a bit quickly and want to cover this up with something before getting the proper primer on for the respray. Any ideas? 

[danm]

Red Oxide. Available in all sorts of places online and in town.

 

Even toolstation and screwfix! :)

[Daz1968]

Best is epoxy primer as it seals out moisture

[Ben_O]

I use Zinc primer as it is not as porous as normal primer.

 

Modern red oxide primer is basically just regular primer but in red and is very porous. I can't comment on the difference between brands but i used red oxide on a previous Mini and it was rusting through the primer within a couple of months.

 

I bought my Zinc primer off of eBay quite cheap. It is called SAS. I sprayed the insides of my floors and the bulkhead inside and out straight to bare metal back in January and there is no sign of rust whatsoever.

 

I shall be using it on the rest of my shell as i think it is very good stuff.

 

Cheers

Ben

[sonikk4]

I'm with Daz here. An epoxy primer will be best. I currently use Zinc rich primer which is better than standard primer but ultimately the epoxy will be better.

As to Red Primer unless it specifically states it's Red Oxide then it will more than likely be standard red primer.

[Ben_O]

But aren't there suppliers that label up red primer as red oxide?

[rowanxx]

Three different replies suggesting three different products :') Just going to hand a read about the different ones and I'll check back in a bit.

[sonikk4]

But aren't there suppliers that label up red primer as red oxide?

There may well be but it pays to read what it actually is. Gone are the days of red lead which was good but poisoned you overtime. Somebody did post a link to a red primer used in the boat building industry, now that may well do the job.

I think I will stick to Zinc rich and epoxy primer. Just got to find someone local to me that will put it in an aerosol can.

[Minilegs]

What about acid etch primer?. That's a 4th to consider 😃

[rowanxx]

I think I've decided on Epoxy primer, or possibly Etch then Epoxy Primer over the top. Would prefer it to be in a spray form but I'm assuming this is very difficult/impossible to do as its an epoxy?

[Ben_O]

The other thing to remember if considering a Zinc rich primer is that it will sacrifice itself for minor rust that is in the metal effectively killing it off.

 

My mini got flood damaged in December part way through the restoration and there were lots of bare metal areas before hand that very quickly became rusty. I cleaned the rust off using a nylon brush wheel in the drill and then sprayed the SAS on liberally paying particular attention to the seams and it really has stopped anything coming through.

 

Ben

[MrIan]

I'm in the middle of also restoring a 70s XJS, I put the floor pans in 7 ish years ago and one side I stripped and painted with zinc primer the other I just keyed the surface and painted with zinc primer. Car's in a damp garage and the bare metal zinc primed is as new with not a mark on it, the other has traces of surface rust. So I'd use zinc primer onto bare metal everytime now as i've proven to myself it can be relied on.