My first experience with wood from a sawmill

[Jerry Herrington]

I'm building a screen door for a Galveston beach house and decided to use white oak. Found some at a local sawmill - 4/4 S2S. It looked straight at the mill, but after sitting on my workbench in the shop overnight, 3 of the 4 boards were slightly bowed. I stickered it for a couple of weeks and nothing changed.

Today I decided to cut one of the rails from one of the bowed boards, thinking a shorter piece would be easy to straighten. Jointed one side flat, jointed one of the edges and took it to the planer to flatten the second side. After planing, the board is once again bowed slightly. Grrrrr! It is now 3/4" thick and I really don't want it any thinner than that because I plan to use mortise and tenon joinery to assemble the screen and don't want the tenons to be so thin that they are weak.

Any ideas as to why the board bowed after planing the second side? I'm a little frustrated.

[Steve Demuth]

It likely was case hardened (significantly dryer in the surface layers than in the interior), so removing the surface 1/16" or so with the planer released stresses in the wood to cause the bow. It may not have been dried properly at the mill (you didn't say whether it was kiln dried or not). In any event, it's not uncommon for wood straight from a sawmill to require some time in it's new environment to reach equilibrium through and through. If your wood hasn't had that, the risk that it moves appreciably during prep is high.

[Lee Schierer]

Sorry to hear of your problems. Wood from a sawmill is not necessarily ready for milling. White oak takes a good while to air dry to stability. Humidity levels in south Texas don't speed that process. Removing material from one side leads to imbalance in your wood which resulted in additional changes in straightness.

If you are going to continue buying from a sawmill, you need to get and learn to use a good moisture meter to measure the readiness of your wood for projects.

[BrianD King]

+1 on the moisture meter and asking about drying processes. I stick to kiln dried lumber, unless it's a pretty thick slab that's air dried for quite a while that I will use for live edge work.

[Jerry Herrington]

Thanks guys! Looks like I have $100 worth of white oak I can't use for a year and my wife wants the screen done like...yesterday! Lesson learned. What is the likelihood of wood purchased at a place like Clark's Hardwood Lumber in Houston being stable without having a moisture meter? I saw some VG fir there last weekend that looked nice and straight.

[Doug Hepler]

If you buy from a reputable lumberyard and they say its kiln dried, it will probably be kiln dried and fine to use.

[John K Jordan]

Thanks guys! Looks like I have $100 worth of white oak I can't use for a year and my wife wants the screen done like...yesterday! Lesson learned. What is the likelihood of wood purchased at a place like Clark's Hardwood Lumber in Houston being stable without having a moisture meter? I saw some VG fir there last weekend that looked nice and straight.

My first thought also was it may not have been dry. When I saw white oak I stick and weight it and let it air dry for a LONG time. If yours is not dry and you sticker and weight it you could probably at least use it for something else later.

BTW, I find a moisture meter a very useful shop tool if you dry your own wood like I do or even to test lumber at the lumber yard before you buy. I use a pinless Wagner model but a traditional pin model can be quite reasonably priced.

There is also a way to check the dryness of your white oak without a moisture meter - look up the Oven Dry method.

JKJ

[mark kosse]

Jerry, it also depends on what "white oak" you bought. Trees from the south tend to move more than northern species. IMO post oak and live oak never stop moving although live oak is not exactly a white oak.

[Scott T Smith]

A lot of white oak in Texas is live oak (which has an interlocked grain and tends to constantly move when worked).

As far as determining the MC% of your lumber, pick up a board and calculate the EXACT board footage in it. Then weigh it. If it's dry white oak it should weigh between 3.6 to 4 lbs per board foot.

[Lee Schierer]

Since you are in southern Texas can you get cypress? It is very weather resistant and should make a nice screen door.

[Jerry Herrington]

Thanks Lee, I'm heading back down to the hardwood lumber place in Houston next week. Will check out cypress, as well as other possibilities!!