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Bruce White
20th June 2011, 02:50 PM
I purchased a quantity of waxed blanks in Tasmania just over a year ago, one of which is a beautifully marked blackheart sassafras blank of 400 x 400 x 100. I have kept it in a reasonably stable temperature area since. Just poked it with my newly acquired moisture meter which gives readings on the outer edges of around 6% and in the middle of around 8%. Itching to get into it but do not want to have it crack from turning it too early. I plan to turn a large bowl from it. Am I safe?

bellyup
20th June 2011, 03:36 PM
Hi Bruce,
The 6 and 9 % readings sound very low - from memory about 15% was bone dry. Might pay to try your meter on some other bits and pieces you have lying around. I'm sure some of the boys here will give you a definitive answer. Good luck with the platter.
Bruce.

Bruce White
20th June 2011, 03:59 PM
Right you are bellyup. Changed my glasses - the meter has two columns of numbers - read the wrong one. The blank readings are in the 15% to 18% range. Tested a bone dry old jarrah blank and that showed 14%. So is 15 to 18 acceptable?

Skew ChiDAMN!!
20th June 2011, 07:13 PM
That sounds about right. It depends on your area (and the average ambient MC) what the final figures should be, but I'd be happy to turn it now if 'twas here in Vic.

One way to guesstimate the figures for your locale is to find a bit of exposed, but "well protected from moisture" timber in your shed, garage or under your house, something that you *know* should be well 'n truly dried and give it a buzz with the moisture meter. A bearer or joist would be ideal.

Bruce White
20th June 2011, 07:42 PM
You are spot on. The old dry structural timber is around 14% to 15%. Rechecked the blanks. They are all in the 14 - 18 range, (a mix of sassafras, myrtle, myrtle burl, blackwood and leatherwood) and are of various sizes. I guess the variation is due to the size difference.

Beauty -they are about right so I will be into them! Thanks for your help.

Christos
20th June 2011, 08:02 PM
Do post results.

nalmo
20th June 2011, 09:08 PM
It will also depend on the type of moisture meter. For accurate results, the actual readings need to be adjusted for each particular species of timber. The meters usually come with a table of adjustments for different species & types.

The actual numbers are not of significance, what you are looking for is the lack of change in the readings over a period of time. That being said, the EMC (equilibrium moisture content) will depend on the ambient conditions and will change slightly with the seasons, room heating and airconditioning.