So I am playing with finishes for the first time and experimenting with polyurethane. My problem involves quoting the instructions on the can and giving some background into my process. Bear with me.
From other answers on WW I understand that applying only a few coats of poly can be sufficient but traditionally you could use as many as 21 over the course a year. Since I don't need an exercise in futility I opted for 3 coats.
I did 2, what I thought were, thin coats 3 days apart and the last one was 2 days previous to now. I did not sand between coats; again because it is not required between coats (Again based on other answers required).
Referencing steps from the directions on the can and the Minwax website
Apply a THIN coat of Minwax® Fast-Drying Polyurethane using a high-quality natural or foam brush.
Let dry 4-6 hours. Then lightly sand entire surface with fine sandpaper (220 grit) to ensure an even finish and proper adhesion. Remove all dust.
Apply second coat. If third coat is desired, repeat step 5 before application.
Aside from the lack of sanding between coats I adhered to the instructions rather well.
I left the table to cure in my shed. Issue with that was my shed seems to have become a haven for boxelder bugs. Which would be an issue except they pissed on the table in several places. Some of it just chips off but I needed to sand out several of them. Sanding with 220 grit with only a few passes it looks like I sanded through the two coats down to wood!?
Why would they suggest I sand with that grit if it takes away the coats to begin with? Obviously they didn't intend for that to happen and I am doing something I am not supposed to do. Should I have used a finer grit? Are my poly coats to thin?