Paint area not blending with the body

[Needer]

Hello everyone,

I've had a rust spot on my Lexus IS250 since forever and I recently decided to finally do something about it !

After gathering many information from videos and threads on different websites for weeks, I felt I was ready to begin with the repair.

I already had many different products in my possession (polish, compound, clay bar, putty, primer, spray paint, clearcoat, ...) as I knew some day I would have enough time to try and enjoy detailing my car.

Before the "big task", I successfully managed to erase a few clearcoat scratches which boosted up my self-confidence and gave me strenght to go on with the rust repair. Yes, I was a bit afraid with the idea of sanding my car body to bare metal ! Anyway, this isn't the topic here.

I roughly followed this procedure :

• Sanding the rust spot to bare metal and verify that the rust didn't contaminate the undercarriage or went through the body panel.
• Apply putty mixed with hardener (I chose polyester putty).
• Sand it to get a smooth result.
• Apply finishing putty to fill the smaller holes.
• Sand it to get a smooth result.
• Apply three coats of primer (I chose white spray primer) on a larger surface than the rust spot (to blend the paint).
• Sand it to get a smooth result.
• Apply three coats of spray paint on a little larger surface than the primer (again, to blend the paint).
• Apply three coats of clearcoat on the same surface as the spray paint.
• Wetsand the whole area and even a bit further into the old paint.

In an effort to blend the new paint with the old, I used a technique found on many websites : stick folded sheets of paper on the body panel when spraying so that there is a smooth transition between the old and new paint.

The result isn't so bad in my opinion, but the big problem is that the new paint doesn't blend at all with the old one. I didn't think it would be so visible, as you can see on the below pictures.



For better understanding for you, I added color on the picture on the right : the red line is where the rust was located, the green area shows more or less the "primer area" and the blue area the "paint and clearcoat area". Of course I unhooked the rear bumper as it wasn't contaminated with rust.

So I got three questions for you :

• I would like to improve the result and I thought (I really don't want to redo the whole process) I would reapply one or two layers of spray paint a bit further than the blue area and then some clearcoat to try to smoothen the rough transition. What do you think about that ? Please keep in mind that I want to avoid having to sand everything back to bare metal and start again.
• What I find disturbing is that the new paint seems to blend perfectly with the bumper, any explanation why ? Is it some sort of optical illusion caused by the gap between the bumper and the body panel ?
• Finally, if you look carefully on the picture, you can see that there is a "spiky part" in the painted area (on the curved edge) which blends perfectly with the old paint and I really don't understand why. Any hint ? Did I wetsand too hard and removed my new paint on this edge ?

Thank you for reading so far and excuse me for my eventual mistakes. English if not my mother tongue and I'm not a detailing professional as you can see !

I really look forward to reading your advices, answers and opinions about this !

Needer

[Bruno Soares]

Not sure you’ll get many responses here, this is something an expert from body shop area needs to weigh in. You can’t fix that with detailing. I think the only way is to blend a larger area and not use a harsh barrier that creates a line, you’ll need to lightly mist the paint on the good area to fade the color differences. Probably not easy to do it yourself.

[Thomkirby]

Does not look bad but is that the basic white or the Pearl White?
My GS350 has the Pearl White and the pearlescent is added in the clear coat. Pearl colors are a really hard thing to match even at the body shop. Good body shops avoid doing what you did for the reason now that you can see with your efforts.
If it helps even Dr. Colorchip will not sale a match for the Pearl paints.

I give you a gold star for doing all that work but alas, color matching is a tough thing.

And my GS350 has had the entire rear of the car repainted and it blends in well but time will tell.

[Mike@DedicatedPerfection]

You mentioned spray paint. Did you have your paint code mixed into spray cans? Either way, from what I can see that looks like two different colors of paint.

[Needer]

First of all thank you for your answers.

My color code is 1G1 which is called “hakuren silver metallic” or “tungsten pearl metallic”. Basically it’s kind of a silver grey but I didn’t think the “pearl” part would make it harder as Thomkirby sems to be saying. And yes I bought a spray can with this exact color code from the brand “Motip”. On their website they say that the color may slightly vary. I didn’t pay attention to this earlier.

From what I gathered paint blending indeed is really hard, anyway way harder than I first thought it would be. I think the result is better than the rust spot but still ... I was expecting better !

I’m not looking for perfection but should I try and spray a little bit further into the old paint and then clear coat it ? Or should I let it like this to avoid making it worse ? What do you guys think ?

[Mike Phillips]

Just to chime in,



This option.

Or should I let it like this to avoid making it worse ?

All things considered, I think it looks great.

It is difficult to get the perfect color match, even for regular body shops. The fact you did this at home in your garage means a lot.

I'd let her go.... polish and wax.

[Needer]

Thank you for your advice Mike. It seems indeed like the safe and wise way to go.

And thank you everyone for your help and encouragement !

[Mike@DedicatedPerfection]

Now that you mention the paint was matched to your color and filed in a spray can that partially eliminates the matching color issue. However there is still room for human error when the paint was blended and put in the can.

The only way for you to have prevented this issue was using piece of metal and prepping/painting it and holding it up next to your car and verifying that it matches your color.

At this point nothing you can do to make it match short of completely re-doing it which would include sanding everything off and starting over. I'd leave it as is and live with it.