Is there a massive disadvantage to use a rattle can primer for a tiny area

I have a rear quarter panel with a bit of a rust of the arch.

I planned to sand the rusty paint down to the metal and spray a little primer on the metal.

But for the sake of such a small area can I get away with using a rattle can just for the primer? Or will I pay a price with some orange peel later down the line?

Your problem won't be orange peel, rather the rust returning. Spray cans, of the 1K variety have a primer which gives no protection against rust, in fact absorbs moisture. So repairs done this way simply don't last.

To do it properly the repaired metal needs to be coated, preferably in an epoxy, that will seal it and provide protection against the rust coming back.

The problem here is that these products often come in kits of 4-5-6-7 litres and that makes the cost prohibitive when all you need is 100ml. I understand that Spraymax have a 2K primer in a spray can. This might be a better solution for you.

Hi

That makes sense.... To be fair I think my local autoshop does have smaller tins of epoxy. Rather so I will use it again in future I am sure as I want to practice some basic repairs even on some body parts I can buy from a scrap yard

Many thanks for your response

My other question is in regards to the blending with in the same panel.

As it's a full rear quarter panel.


Am I best sanding 600 in the problem area... Then taking it to 1000 up to the body line.

I may be post posting a picture under a new thread. But my main confusion with blending in the same panel is do I need to remove the clear coat from the entire panel or can I get away with just sanding to a body line?

If I can sand to a body line. How do I make the abrasive edge 'disappear'... Would a paint blend aerosol do the job and melt the abrasive edge?

It would be much easier and avoid duplication if you put this in a single thread, or at least limited yourself to asking in just one thread.

I've already addressed your question of grits. No need to repeat that.

If you're going to fly mask then you only need P1500 on the face that will be cleared (i.e. below the line). Use a block to make sure you don't sand above the line or use tape to protect it. You then position the folded tape so that clear can only be sprayed to the edge of the sanded face. After the paint has been sprayed, cured and masking removed any minor marks or buildup can usually just be removed with hand polishing with a mild compound.

Search my posts for fly masking. I did one that had a few photos and details of how the tape has to be folded.