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I'm late to the party so I apologize, but are you able to completely level the finish on the top? You need to be able to do this before spraying the final couple of coats. As far as sanding goes, you can sand at 90 degrees to one another and it's easy to tell if you're ready to move on, straight deliberate strokes not random circles. Sorry if I'm redundant with this.

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Jim Watts
http://jameswattsguitars.com

Talking about the torrified spruce, right? I thought I had it level; truth is I'm not sure I know how to tell it's perfectly level. I was doing 360 in between each days coating. then talking about sanding issues on #1, I was sanding at 45 degree angles, that's how I know it was the 800 grit I didn't completely remove. Next I went to 1000 hand sanding with the grain. I'm surprised I didn't see the remaining 800 scratches. After 1000 I just used the random orbital.

Jim is right -- you need the finish perfectly leveled before spraying your last few coats. The finish I'm seeing in the photo is nowhere close to where it needs to be - at least, if you are aiming for a professional quality finish (for example, Collings guitar).


When level sanding you need to be under very bright lights - ideally coming from a couple different directions. You want to be using high quality sandpaper designed for finishing work - Home Depot won't cut it here. I would do the leveling with about 400 grit. I strongly recommend to use paper from Kovax brand as it allows you to do dry cleat coat sanding. It is expensive but there is no better sandpaper as far as I know. Look at the Super Assilex line. You sand until the entire surface is deglossed - you should see no shiny spots at all -- that's when you know the leveling process is complete. Additionally, you shouldn't see a single pinhole or anything after this. If you do, fix it before proceeding.

Spray your last few coats and wait the required time -- and then come back and start leveling with 600 grit or higher. I strongly encourage you to do the level sanding by hand. You need to use a sanding block or you won't level the surface properly.

Good finish work is just a ton of sanding and there are no shortcuts.

When we sand scratches out of clear acrylic windows on aircraft, the process is to sand in one direction with a grit, get it smooth and follow by sanding at 90 degrees to the existing surface till we can't see any cross-grain scratches, repeat with next higher grit. That way we know the 400-grit scratches have been completely eliminated by the 600-grit sanding, and the 600-grit scratches are eliminated by the 800-grit sanding - - - till we're done.

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Peter Havriluk

Everything happens for a reason....sometimes the reason is you're stupid and you make bad decisions. I used some 400 grit and tried to see how level things looked. Back and sides were pretty good, didn't take all that much to get any low spots flush. The top was horrible, and now I know why. I obviously never did any sanding past the 80 grit or so that the drumsander did when thicknessing the plates! I hafta say, quite a few people here were very generous with their advice, when I was just wasting your time based on not understanding things I should know by now. Good news is this top is gonna look just fine. Meanwhile, I'm thinking of getting different spray gun before I respray. I did go thru the lacquer in a few places on the sides. I need to experiment with setting up a spray gun better than I typically do. Thanks again. Roy

I remembered this thread, and it seems a good gathering of folks that like to use torrified products.
We just received back a pallet of Sitka Tops we sent 8000 miles round trip by truck, barge, and truck, 2 ways to get roasted. Being flush with this product, 3A torrified Sitka is on sale for $60/set and with quantity discounts enabled. Select torrified variation of 3A Non-figured Sitka Dreads product sort in our store.

With my normal work output, I have finally finished the respray of the back and the wet sanding and hand polishing processes.

Thanks largely to advice from people who tried to help me understand the details of wet sanding thru the grits, this is the best finish I've done on this.... my 3rd guitar.

Just thought a final post on this topic was apropriate. Again, thanks.
Roy

Congrats, Roy !!! Looks like you did a terrific job.

The key to a good finish is just lots and lots of sanding and prep work. It's easy to move past that phase too quickly as everybody hates sanding