It just might work! We have been having a real cold snap in our area the last few days. Probably nothing compared to what most of you are used to, but certainly in the temperature area that can cause a wet balsa core to try and unglue itself. Nighttime temps down to 15°. So I broke down and dug out my big Mr. Heater and tented the hull off and stuck the thing inside running on low. The tank has lasted much longer than I thought it would and the key thing is that directly above the heater the surface of the glass is showing 115°. That is the high temp reading, but it covers about a 2' x 2' area and then drops off quickly.

The reason this is important is that if I can get an area of hull to reach that temp or preferably something over 120° then the process of boiling/evaporating moisture from the core under vacuum becomes much more likely. So with ambient temperature at something more friendly like 45° then reaching the higher target temps is realistic and manageable. I would also expect that the area that was suitably warmed up would be larger too.

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We are in for it this weekend too, with snow coming that will be topped off with freezing rain. So the work will have to continue inside the warm shop. I won't be doing anything to this hull until we get reliably above the 45° mark. As soon as I have any kind of results with this vacuum drying technique I will report it, either good or bad.

Dave Graf