Metal hole punch - what size for arcade buttons?

[Bobbler]

Was originally going to go for drilling and filing out the button holes on my control panel, but just read a few threads on here about the metal hole punch from Greenlea. Sounds like a great idea and far neater than drilling multiple holes everywhere and joining them up

My question is what actual size do I need for an arcade button punch? I see a few using 1-1/8" from Greenlea but when looking at the schematics for a button ( http://www.gremlinsolutions.co.uk/images/compmountbig.gif ) it shows 1.10"
Wouldnt 1.1/8" be a bit big? I just cant visualise fractions of an inch because of my metric brain

Any help appreciated as always so I can get one ordered up for next week.

[javeryh]

Well, 1-1/8" is only 1.125" so it's only 0.025" bigger and if we're talking diameter then it's only 0.0125" bigger all the way around which it practically negligible - also the bezel trim on the button will cover the hole anyway.  I think you are safe going with a 1'1/8" hole punch.  All I've ever used to drill buttons in MDF and plywood is a 1-1/8" forstner bit and it works great.

[Ken Layton]

The Greenlee knockout (a.k.a. "chassis") punches are available at Home Depot in the electrical department. The punch for 3/4" electrical conduit punches a 1-1/8" hole (28.2 mm). Mouser Electronics also sells the Greenlee punches.

[Bobbler]

The Greenlee knockout (a.k.a. "chassis") punches are available at Home Depot in the electrical department. The punch for 3/4" electrical conduit punches a 1-1/8" hole (28.2 mm). Mouser Electronics also sells the Greenlee punches.

Thanks for the info guys. I am in the UK so Home Depot is out of the question (though I am in Florida over New Year time )
I have managed to find a similar item over here so will get it all ordered up.

Thanks again