hi all, just to close this one off & in case anyone is searching in future for tips on router, hatch & cutting a hole in deck here goes. I hired a router today, made a template & stuck it down with tape, shaved off a few mm with each pass & kept rechecking my measurements. Well what a fab performance! routers are the best & clearly made for the job.
Some more tips:
Practice on a bit of old wood first, these routers have a mind of their own.
Hold the machine with both hands & put pressure down or it jumps up & wanders off.
Try adjusting speed, about middle did it for me.
Start in a smaller hole in the template, then work outwards nibbling away at the hole to make it bigger.
Buy a hatch with a big overlap!! mine had 1/2 inch of clearance so could afford a mistake or 2.
I got loads of plastic filings on me now & they are itchy so cover your arms & nose.
End result is tops, when I´m out this weekend I´ll have 1 hand on wheel, 1 on throttle & eyes fixed on my new hatch!!
Cheers all, top advice as usual. Anyone coming this way to Spain pm me & I´ll show you the sights.