Hi Chris
Purchased some maple 1" x 19mm planed all sides to put a boarder around the floor. I used BritishHardwoods - presuming you are in the UK, they are a great service and a amazing price on the wood IMO. Obviously, I`ve no connection with them but was local enough to visit this evening.
As I`ve done more sanding I`ve also noticed that the gaps become more visible where the parquet blocks haven`t quite met properly. So this evening, I also purchased some Lecol 7500 filler, the stuff you mix with fine sawdust and then skim it over the floor to fill any gaps. I haven`t used it yet, but i`ll let you know how I get on.
I`m also going to inlay some blocks using my CNC machine. I posted pics a few weeks ago under my aluminium cnc machine build - you`ll see it under project logs. I`ll be insering the inlayed blocks around the perimeter being the maple boarded.
It has to be said, that it is going better than I expected.
Before you start laying, one piece of advice - make sure if you are fitting herringbone style, that your centre row is 100% spot on. If not, it throws the rest out completely!