If one of your balls gets a nick on it, it can do a lot of damage before you might notice.

I clear new playfields.

It lets me become intimately familiar with the game upon reassembly and I have a protected playfield that looks like glass.

Yes, clear does not stick to Mylar very well, so it has to come off.

For a beginner, nothing is easier to lay down and get perfect than JC660

http://www.bapspaint.com/docs/psheets/PPG/Automotive/Shopline/JC660.pdf

If you painted cars for a month professionally, you are overqualified to clear playfields.

Plus you clear them flat on their backs, so no runs or drips!

I've got some Devilbiss guns, but honestly, I've used the $10 Harbor Freight HVLP guns many times when away from my own shop and they work perfectly.

Sometimes with old Ballys, the "heat' from the clear can react with the plastic of the inserts and make little spots. On those games, I mix the fastest hardener with the clear so it does not have time to react.

I also have some real Diamond Plate clear that I use.

But if you have never done a playfield before, stick with the PPG.

Don't even try sanding off the clear coat.

It's not a real clear coat like you are thinking, it's often just a layer of clear silkscreen over the last batch of ink.

Just lightly scuff up the surface with around 800 grit to give the new clear some "tooth"

The next update to my Playfield Restoration Guide will be clear coating, so if you have any doubts in your mind, wait until you read all the details.

http://pinside.com/pinball/forum/topic/vids-guide-to-ultimate-playfield-restoration

That is the 10000$ question...

Maybe mask it off and feather in.

Myself, I'd hate to put it under more clear in case it hazes or needs to be totally replaced one day.

I'm working on the road, so I can't really spray in my hotel room (although I have a complete solder/rework station spread out over the desk in the room).

Hopefully it won't be too long. In the meantime if someone has questions, I'll keep answerin'.

Don't be afraid to practice on a crap playfield, or just a painted piece of plywood.

You will be pleasantly surprised on how much build you get in a single coat of clear (maybe 4x what a coat of poly builds), and how high of a gloss you can put on it (maybe 3x over poly).

Spraying coats 10 minutes apart does not suck either.....

All it takes is a nicked ball....