Really impressed with your work, Timbo.
You must of had some sort of restoration experience, because your techniques and results are A1 !
Any particular reason why you lay 2 coats of clear and then comment touch ups ? Is that to seal the current "wear" and then just build on that ? Why wouldn't you just touch up the bare playfield ?
Keep the updates coming mate - really enjoying your thread.
As far as artistic skills, I'm 10 thumbs - but I've done a fair amount of research, as I really had to prove to myself that I am 10 thumbs :)
An initial clear is crucial before doing touchups. Doesn't need to be a significant amount, but it's important because it allows you to wipe any mistakes off if you are unhappy with the initial touchups.
I'm looking forward to seeing the playfield retouch!
