Painting Techniques

[170C]

I have a fiberglass item that was damaged. The damaged area has been repaired, cleaned and painted. Paint is now being allowed to dry and won't be worked on until next weekend. What is the correct method of feathering the new paint to the old paint? I suspect where the new overlaps the old paint that a very fine sanding is the procedure, but I have no experience doing this and need suggestions as I don't want to mess up my just completed (partially) paint job.

[GAHorn]

Without knowing more about the nature of the "fiberglass item" I'm not sure quite what to say. (I guess it must be a "privacy" issue for you.)

Whenever I paint anything that must meet-up with a similarly-painted area (like a wingtip fairing which will go back onto a painted wing) I paint the entire object to avoid obvious new paint/old paint contrasts on the same part. For example I would not paint only the leading edge of a wingtip fairing...I'd paint the entire fairing.

If the area to be painted is an unremovable part of a larger object...such as a panel on a wing, etc., then I paint all the way to the nearest seam or assembly parting-line.

If it's a "spot" area to be painted, ...I"ve had success cutting a hole in a piece of cardboard and holding the cardboard away from the surface to be painted about 6-inches, I shoot the paint thru the hole at the spot...using the cardboard as an over-spray mask. This prevents obvious masked-edge areas. When the paint dries....if it's still obvious as new-paint....then automotive polish or compound will blend them together.

I think you should "own up" to what you damaged and how you damaged it so we can all learn from the experience. Write an article for the 170 News about it. Becky will find out about it sooner-or-later anyways.

[170C]

TRUE CONFESSIONS Let's just say that one each fiberglass wing tip met one each metal hangar door and neither one won. Details at 11:00 Minor damage to the rear of the wing tip--about a 6 inch area. As those who have the fiberglass tips know, the most aft portion of the tip is the widest part of the tip. Minor damage to that most aft part of the wing tip The damage was repaired via body filler (bondo) sanded smooth and has had two coats of paint applied plus two coats to one area that needed painting anyway. All of this probably amounts to 5% of the total wingtip area or less. I didn't want to repaint the entire tip. Paint/color appears to match since it is the same brand/color as original. I am thinking that where the new paint overlays the old paint that I need to compound or sand with a 1000 or higher grit paper, but I don't want to leave any sanding marks. This is why I was asking the question because you paint pro's likely know the "proper" way to treat this unit. I do have sufficient paint to repaint the entire wing tip, but much prefer to not do so. Now George, I have spilled my guts

[LBPilot82]

As long as the underlying repair is flush and smooth, sanding first with 1000 or 1500 should blend them well. Once the edge of the paint is smooth, wet sand it with at least 1500 or 2000 grit and then polish it with a wheel and light compound. Meguire's make a really good product that used to be called "body scrub" and is now called "fine cut cleaner" that is made for a polishing wheel. It works great. When you shoot the paint, like George said, don't mask it. It will create a hard line that when attempted to be sanded out, will sand out the existing paint too.

[170C]

Thanks to all! No masking tape has been used so the sanding & compounding should do the trick. Then we'll see if George can determine which wing tip it is