I agree that if this becomes a regular event that frets are not a requirement. I also see no problem with a 2x4 with bailing wire for strings if it can be played.
Cigar Box Guitars, Diddly Bows, Cigar Box Violins have no rules. Kids and adults alike build them out of whatever they can find.
So, for now, Godin set the rules. This contest week is his show and he says what goes.
If you want a "frets optional" competition, start one. If you want a "build a guitar from a 2x4" contest, start one. Just don't start them all at the same time. I want to participate in everything I can. If 14 of these things are going at once I'd implode from the stress.
Hmmm... 2x4 you say...
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BTW, I finished up my CBG last night. The weather outside is sucky so I'm just waiting on a little sunlight to take the pictures. It plays better than the other ones I've made, has an experimental headstock and a few other interesting quirks.
I'll be recording a quick tune on it tonight to post with the pictures.
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I have a wine crate for about 6 bottles that I'm looking at making something out of that. Either a wine box bass, or a Bo Diddly Telecaster.