Working to figures

[tonydxn]

'Working to figures' is a very useful expression I just picked up from this message board. (Means building instruments to specified dimensions) It's pretty much the way I build (guitars mainly, but also some flatback mandolins).

I'm just embarking on my first adventure with an F5. I've got my Stewmac kit complete with Don Macrostie's plans, and I've got Roger Siminoff's (old) book. Right, so how thick is this soundboard meant to be? DM's plans show 4.5mm at the thickest point. RS's show 6.5mm. That's a helluva big difference.

Which figures am I supposed to be working to, or do F5s really vary that much without affecting their performance?

[Chris Baird]

My Stew-mac plans say .250" for the top middle I think thats 6.25mm. I wonder if they changed it? Anyway, start with .190-.180". I'm not sure which Loar Siminoff gets his measurements from but they seem thick to me.

[Michael Lewis]

4.5mm will make a stout top, unless you are using VERY soft wood don't make it 6.5mm.

[tonydxn]

Thanks for your advice guys.

The recent contributions to 'Loar Specs' have been really helpful too.