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I recently pulled the fingerboard on a guitar with a poly finish and ended up with chips of finish coming undone. The effect is much like what I've seen of Tacoma guitars in that the finish lifts off and becomes cloudy looking. Rather than fight with gluing down the chips in an attempt to repair the cloudiness I decided to just remove the offending pieces of finish altogether, mostly because when I tried to put Cyanacrylate in btwn the wood and the finish, it wasn't happening well.

Now it seems that the wood itself has no pore filler under the poly and I'm looking for advice on how to best go at this. If you all would please, throw me some ideas?

TIA

This is one place I do use CA glue and have fixed a number of guitars for chips on the side of the fretboard. Since you already peeled back the flaking finish then you are at the point of just getting finish back on the spots. First thing I would look at is how thick the finish is and if it will even be possible to drop fill it with CA. If you have a thick finish then I would wet sand it down to smooth out the edges. You will need to feather the finish back far enough that after it is buffed out you don't see the dips where you sanded it. I would use a small piece of wood as a backer for your sandpaper and be very careful not to sand the wood. Depending on how think the finish is will determine how much to feather it back. You do not want to do more than is necessary. If it is not very think then you just want to make sure you have good adhesion of the old finish and no loose spots. I use a photographers loupe with is very high power but a good magnifying glass is needed to look very close at the edges for anything that is loose.

As far as filling the missing pore filler (which I assume came out with the chips). you are going to have match the filler that was there. I have an array of Mixol tints just for matching colors so I would use some natural colored grain filler and tint it to match. This requires doing some testing on a scrap of wood (the same type as the neck). If you don't have tints then you will have to find a way to at least come close or those spots will scream repair...

Once I had the grain filled then I start drop filling. You can use a toothpick as brush-like tool to drop fill. I usually have a bunch of them at the ready since they will get gunked up. You need start out filling up to (but not over) the original finish. As you get the finish built up you will keep moving closer to the edge until you fill up to the edge of the area you feathered out. I don't use accelerator so I give it plenty of time to set up. After you get the drop filled area filled to the level of the old finish then I wet sand it using the same piece of wood as a backer and wet sand the area to reveal high and low spots. Repeat drop filling until you get a perfectly smooth and even finish. Then buff it out.

I have had a few that the finish has been cracked all along the joint between the fretboard and neck. In those cases it is easier to just sand the finish off the complete length of the neck and refinish the sides. That is a much bigger job than just drop filling because you have to blend the edges into the old finish. I would do that with my spray gun and I would put the same finish on that it originally had. It is actually faster to do it this way than drop filling but is something I would charge a lot more for doing. If you were a client I would tell you that drop filling is not perfect and I am confident the job will be a solid repair but you may see where it was fixed. If I sprayed it I would guarantee that you would not be able to tell it was ever repaired.

Hope that helps,
Bob