I'm still working on my ERC, but I didn't have any trouble with it warping. Lots of other obnox, sure, but not warping. I roughed it out and then let it dry inside a while. If you are worried, leave it somewhere between "pretty wide" and "full width" to help keep it from warping. I'm sure some of these guys who have turned out really pretty ERC bows will chime in shortly.