Low Moisture Content in wood how to increase..

[wolfau]

Hi Guys,

I have come across a fair amount of roof battens that may be thrown out. It was identified on the forum as Vic Mountain Ash.

I own a Wagner MMC 220 and did a moisture check at a specific gravity of .7 or 70 on the MMC220.

The read out is 4.8. I was told by an experienced woodworker that the best moisture content is generally between 10 to 13%.

I want to use the wood to make cutting boards.

Is there a need to increase moisture into wood and is there a way to go about it?

Thanks in Advance.

[BobL]

If you are going to make cutting boards by gluing strips together in parallel the amount of along the grain expansion will be small and the amount of across grain expansion doesn't matter.

I's only be worrying about expansion due to increased MC f you were going to use them to make furniture.

[wolfau]

Thanks Bob for the reply.

[rustynail]

Kiln dried timber, particularly the Tas oak type material requires reconditioning which is replacing part of the lost moisture. As BobL has said, for your particular use the low moisture content is not a major issue. In fact, it will work in your favour when it comes to sealing the made up cutting board - whatever oil you use will soak well in and there is your moisture replacement.

[auscab]

Just cut then close to size and let them sit a few weeks in your shed , then make the boards . This would only be necessary if they have been sitting in the wet for months after being taken out of the house where they previously lived dry.

If they haven't been getting very wet then its probably ok just to use them.

Rob

[wolfau]

Thanks for the replies and the replies confirms my thoughts as well. Recycled HW might be the way to go to make stuff snd its fairly cheap to buy as well.

Thanks Again

[John.G]

An MMC220 is a good bit of kit.
And 4.8 is very low for Melbourne. Up in a roof for 30 years.... yeah maybe.... but 4.8 is more like Oodnadatta or Thargomindah then anywhere within 40 mile of the beach.

So couple of things to check.
1. Meters do lose calibration sometimes if the battery has been let go flat. So if at some point there has been a dead flat battery in the thing just changing batteries may not rectify the thing and it needs re-calibration by a technician. So check on a few other bits of wood or cross check with another meter to make sure your meter is reading fine.
2. Different woods have different electrical resistance properties. There should be with the meter (being a Wagner) a species correction chart that will tell you to add/subtract whatever % to the screen readout depending on species. if not contact the supplier to ask for one. Its a pro level meter and they should have this info.
3. Electrical resistance properties of wood change with temperature. There should be with the meter (being a Wagner) a temperature correction chart that will tell you to add/subtract whatever % to the screen readout to allow for the ambient temperature of the wood. If not contact the supplier etc etc... its a $500 meter you should get this level of service without asking. This correction is applied in addition to the other correction for species.

[wolfau]

Its a new meter and have tested it against vic mountain ash and other species and gives a good reading.

The timber has been sitting under roof tiles for nearly 60 years and has very very faint cracks in it from the drying.

The specific gravity tech details I use is from Britton Timbers.

The other thing I need to worry about though which the home owner reminded me of is Asbestos because it was prone in the area.

Thanks