Moisture content

[JWD]

I’m looking at picking up some English walnut blanks and it says moisture content 30% - what would everyone recommend doing with them? Are they ok to be turned straight away? Or shall I leave them for a while? Or do a rough first turning?

 

[Honest John]

30% sounds a bit high, but then if you are talking bowl blanks 3 inch thick or more, I suspect that’s probably fairly normal. Bowls turned from wood this wet and then taken indoors into a centrally heated house is certainly going to move. I suspect this level of moisture is perhaps what many suppliers call “part” seasoned. I would part turn them, weigh them, and set aside to dry further. I don’t recollect turning European Walnut before, but I’m sure I’ve read somewhere that it can be splintery and contain a lot of voids. I could be completely wrong on this, so I’m sure somebody will be along shortly to put us both right. On your part turnings, try to keep the wall and base thicknesses equal to help reduce the stresses. If you leave enough ‘meat’ on the vessel to be able to allow re-chucking and finishing. Re-weigh the vessels every week or two, and when it stops reducing you should have achieved at least some level of equilibrium. I have often wrapped part turnings in newspaper which can be changed every week. Seems to work for me. Good luck

 

[Dalboy]

I personally would rough turn them if you want to use them indoors unless you turn to finished size and watch them warp which in some cases can be good. By rough turning you can get them down to a more expectable moisture level where they will not move when finally turned but don't forget to either put into a plastic bag and turn it inside out on a regular basis to avoid build up of moister which can encourage mould and the like. I seal mine on the outside only and put them in stick with good air flow this avoids the problem of mould.

 

[Lazurus]

I recently did some oak bowls which were a similar moisture content, I rough turned to 1" walls and popped them into paper bags to dry, they did move of course but at 1" walls had plenty left to finish turn to final thickness when dry, just be sensible with how and where you put them to dry.