Hello,

Even though I am a newbie when it comes to nail guns and compressors, I thought that I understood how my new Porter-Cable FN200C nail gun and Craftsman 3 gallon 1 HP compressor was supposed to operate.

Here’s my question:

Before I begin, let me assure you that EVERYTHING was correctly set up. Even though I’m a newbie in this area, I know how to set this stuff up.

Here goes.

When I start up the compressor, it builds up pressure to 125 psi on the tank gauge, then it cuts off. I set the regulator gauge on the output side to 70 psi, then I begin to nail 2 inch finish nails.

After I nail about seven or eight of them, I notice that the tank pressure is down to 100 psi, but the regulator pressure is now BELOW 70 psi (the place where I initially set it).

My question is, WHY, if the tank pressure is still above 70 psi, has the output pressure dropped? I assumed that the output pressure would never have to be reset. I understand that as I use the nail gun, I am using up part of the pressure in the tank and therefore the tank pressure will show a lower pressure than the initial reading, but
I thought that as long as the tank still had at least as much pressure as the regulator setting, it would not require me to reset anything.

Surely, I am not supposed to have to continually reset the regulator pressure as the tank depletes.

What am I missing?

Thanks,
Louis