Repair burn through blend help needed

Don Sweet

Member
Trying to compete bc/cc with Nassau blue motobase and uv clear. 3 coats of clear sanded then 3 more coats of clear. Sanded through clear over rear wheel. I tried to blend the area and though it looked good in the garage so I sprayed 4 coats of clear over it and past the repair area then resanded starting with 800. I was going text to a picture to Barry but the defect don't show on the cell phone so I will post here. So I should have cleared the whole panel. With looking at the picture can you guys tell if this defect is from poor blend or from not clearing the whole panel. Defect is in upper right area. Any suggestions on where to go from here?
KIMG1802.JPG
 
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JC Daniel

Active Member
Clear blends are difficult and will show lines unless you use blending solvent, I always clear the whole panel to avoid the line showing. One of the Guys will be along and give you some specifics.
 

Don Sweet

Member
Clear blends are difficult and will show lines unless you use blending solvent, I always clear the whole panel to avoid the line showing. One of the Guys will be along and give you some specifics.
My thought is if it is from a poor base blend I will just have to reshoot the whole panel and hope that the color matches which I know can be a problem. And if it is in the clear it doesn't seem like just spraying clear over the whole panel would fix it at this point, so go back to square one?
 

JC Daniel

Active Member
It looks like the clear line is showing and would have to be lightly dusted with base before clearing the whole panel. There will be some guys who have a lot more experience to chime in, Wait on them before you move on.
 
Activating the base coat helps in these instances. Generally you can just shoot more clear over the exposed base without any issues.

I had a small sand through on signature car fender except is a bit deeper than most:
Fender Sand through.JPG


This was my first attempt at blending paint so I was extremely nervous.
Here are the steps I took:

1. Sand the entire panel where the sand through is with 800 grit until dull.

2. Mask off the rest of the car to prevent over spray from getting on your nice paint leaving only the entire panel you are working on exposed.

3. Now mask off the panel you are working on (this will be removed before clearing and helps keep you focused on the repair area) making sure to leave plenty of room around your sand through for your blend. You don't want to mask too close or you'll leave what they call a tape line.

4. Wipe your panel clean with Wax and Grease Remover. Let this dry while you get ready to spray - 20-30 minutes.

5. I mixed up a small amount of reduced clear to use as in "inter-coat." This is done by using 30 parts clear, 10 parts hardener, 90 parts reducer. (Note: Now I keep SPI intercoat clear on hand for this purpose.)

6. Spray the blend area with the reduced clear using light coats as you would base coat. You want to go past the sand through area with each pass but do not go all the way to your masking tape. Stop a couple of inches short of that and using your wrist you want to sweep the gun away from the surface. Imagine you are spraying an inside 90 degree corner and you have to turn your wrist to keep from loading the paint into the corner. You will start and stop your passes using your wrist in this manner.

7. Spray a couple of coats of the reduced clear with the second coat extending past the first coat to kind of feather the edge. Remember your base coat will be sprayed on this inter-coat so give yourself some room to work. (Note: the intercoat clear allows you to "see" the true color of the paint surrounding the sand through. This helps greatly in getting a perfect match/blend.)

8. Allow this to flash while you mix your base coat. Mix your base exactly as you did when you first painted the car.

9. No need to sand just begin spraying your base coat very light coats. Make a couple of short passes over just your sand through for good coverage. Make sure to let each coat flash off. By now you will see that things are shaping up and the sand through is pretty much invisible.

10. Make a couple of more passes using the "wrist technique" with each pass going a little farther than the last but not reaching the tape line. Be sure to spray light coats of base until the blend is just the way you want it.

11. Remove the masking from the entire panel where the sand through was and prepare to spray your clear coats over the entire panel.


Hope this helps. I am not an expert by any means but this worked for me and I hope it does for you as well.

The blended repair.

Base coat blended on fender.jpg


Cleared:
Fender Repair Cleared.JPG


Buffed:
Fender blend buffed.JPG
 

orangejuiced86

Garage hack at night.....
When you spot in "Clear" you want to melt the edge down like a ramp which makes it nearly invisible on a daily type paint job. Problem is when you sand it with something heavy like 800 and proceed to go through the grits like you would when polishing you are essentially taking that thin edge and sanding it back up the ramp exposing a thicker paint edge.

Personally when I do clear blends, I wont hit them with much more than 2000 and then buff them out to get rid of any dry spray.
 
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Don Sweet

Member
I appreciate the advice I think I am leaning towards respraying the base as suggested and since I have a hard time laying down nice smooth clear that doesn't need major sanding I will clear the whole panel. Thanks Don
 

Don Sweet

Member
Yes, I put several very light/thin coats waiting 30 minutes between each the last 2 coats I over reduced and also tried to go fade out at edge of repair using as '68 said the wrist movement. In the garage it looked pretty good to my inexperienced decrepit eyes.
 

Don Sweet

Member
Activating the base coat helps in these instances. Generally you can just shoot more clear over the exposed base without any issues.

I had a small sand through on signature car fender except is a bit deeper than most:
View attachment 11409

This was my first attempt at blending paint so I was extremely nervous.
Here are the steps I took:

1. Sand the entire panel where the sand through is with 800 grit until dull.

2. Mask off the rest of the car to prevent over spray from getting on your nice paint leaving only the entire panel you are working on exposed.

3. Now mask off the panel you are working on (this will be removed before clearing and helps keep you focused on the repair area) making sure to leave plenty of room around your sand through for your blend. You don't want to mask too close or you'll leave what they call a tape line.

4. Wipe your panel clean with Wax and Grease Remover. Let this dry while you get ready to spray - 20-30 minutes.

5. I mixed up a small amount of reduced clear to use as in "inter-coat." This is done by using 30 parts clear, 10 parts hardener, 90 parts reducer. (Note: Now I keep SPI intercoat clear on hand for this purpose.)

6. Spray the blend area with the reduced clear using light coats as you would base coat. You want to go past the sand through area with each pass but do not go all the way to your masking tape. Stop a couple of inches short of that and using your wrist you want to sweep the gun away from the surface. Imagine you are spraying an inside 90 degree corner and you have to turn your wrist to keep from loading the paint into the corner. You will start and stop your passes using your wrist in this manner.

7. Spray a couple of coats of the reduced clear with the second coat extending past the first coat to kind of feather the edge. Remember your base coat will be sprayed on this inter-coat so give yourself some room to work. (Note: the intercoat clear allows you to "see" the true color of the paint surrounding the sand through. This helps greatly in getting a perfect match/blend.)

8. Allow this to flash while you mix your base coat. Mix your base exactly as you did when you first painted the car.

9. No need to sand just begin spraying your base coat very light coats. Make a couple of short passes over just your sand through for good coverage. Make sure to let each coat flash off. By now you will see that things are shaping up and the sand through is pretty much invisible.

10. Make a couple of more passes using the "wrist technique" with each pass going a little farther than the last but not reaching the tape line. Be sure to spray light coats of base until the blend is just the way you want it.

11. Remove the masking from the entire panel where the sand through was and prepare to spray your clear coats over the entire panel.


Hope this helps. I am not an expert by any means but this worked for me and I hope it does for you as well.

The blended repair.

View attachment 11410

Cleared:
View attachment 11411

Buffed:
View attachment 11412
'68 that looks awesome thanks for the pics and write up.
 

Don Sweet

Member
On the first repair. After rebasing I resprayed the clear going well past the base coat. I put 4 coats on to give me some material to sand which I always need to do.
 
I always clear the entire panel when making any paint repairs. Blending clear is difficult and I have seen too many premature clear coat failures at the blend lines.
A car dealer scratched the bumper on my car while performing a scheduled service. They promised to fix it so I brought the car back and left it there. Next day I picked it up and it looked fantastic, you couldn't tell where the scratch was. About 18 months later the clear began to change color and started peeling at the blend lines.
 

JC Daniel

Active Member
I can't stress enough on clearing the whole panel, Ask me how I know blends are difficult. I have ate my words and experience enough not to try blending clear even with blending solvent.
 

Don Sweet

Member
I will clear the whole panel and if I have enough base left base the whole panel as well. I think that would be the safest way for me to get the results I want.
 

sprint_9

Rookie
I will clear the whole panel and if I have enough base left base the whole panel as well. I think that would be the safest way for me to get the results I want.
Clearing the entire panel is the way to go. Basing the entire panel can be both good and bad. If you base the entire panel without blending it could show up where it meets the next panel. Everything is new and fresh so you could get away with basing the panel, the key to even trying that without blending the base is to be exact. You have to be exact in how you spray, same gun settings and gun techniques, and the spraying conditions need to be close to what you sprayed initially. If you cant be really close to exact then blending the base is a better option.
 

Don Sweet

Member
This is on the lower rear quarter of a 57 Chevy ht. So I was thinking I could spray from the chrome trim down and over to the door opening, but I would need a good match at the lower part of the adjacent door. This blue is hard to match, not ideal conditions or painter. I can duplicate gun/ spraying setup but not humidity and now it is about 10 degrees warmer. Your point is well taken, thanks.
 

Don Sweet

Member
Chris I actually bookmarked your post helping a guy with a jeep. Super information from you and others who gave their input on blending. I tried to follow you guys methods and I thought it looked like a good blend. So where I went wrong was only partial clearing over the blend. After my normal sanding and buffing I could see a difference in color at the blend it looked a little like silver line at the blend line. Before I posted my problem I didn't know where I had gone wrong was it a blend problem or spot clear problem. You guys straightened me out. I believe I will be OK following the advice given for blending and not spot clearing but clearing the whole panel.
Thanks to all,
Don
 
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