Drying wood in the oven

Ok, let me start off by saying this is not a joke.

I was wondering if anyone has had any success drying slabs in the oven? I had a branch from a big silver maple in my yard come down after a big storm this weekend and I wanted to make some mini slabs instead of burning it or bringing it to the landfill.

What temperature do you set the oven to and how long do you bake it? I guess I could experiment but I always like to have a starting point. The slabs are maybe 12-14" long and maybe 6"-8" wide and I haven't cut them to thickness yet. I was going to try to make some lids for home made fly fishing boxes with the wood so I may start at 1"-1.5" and plane it down from there.

Thanks for the input!

Frankly I don't know what temperature to set it at, but two things strike me:

1. Drying the wood at too high a temperature will dry the exterior much faster than the interior which could cause cracking.
2. The moisture in the wood could boil internally if at a high temp & cause "unwanted" problems, cracking perhaps being the least severe.
3. That is a costly way to dry lumber.

Al,

Thanks for the info! I have never dried a slab in my life, so I have no idea what I am doing. I guess if I was to skip the oven would you suggest drying the logs and then slabbing them? Or do you slab first and then dry? I am just worried about warping and cracking

You might want to read some of this report, or others, by the FPL: https://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr118.pdf
Like most things, there's a lot more to drying lumber suitable for woodworking purposes than one might first think.

John

some of the bowl turners use a microwave to cook some of the moisture out, maybe that is something you should also look at.

If you're married, seriously, I'd check with the wife before I try to dry wood in the oven.
I also don't think its a good idea. Cut your slabs, let it air dry. Why do you want to oven dry it? Are you in a rush?

I actually do the cooking at my house, and the wife does the dishes. I'm ok with that trade off lol. I guess I am not in a rush, but I didnt know if drying in a heat source would help with warping or if I should just let air dry? And you would slab the logs first and then dry, not vice versa? I am a complete beginner when it comes to milling wood. And from the responses I received, it seems to be more than just cutting and drying.

Hi, when I mill lumber I do it in the autumn and stack the lumber outside with a suitable number of stickers to prevent sag.

Seal the ends of the log as soon as you get it, use Lee Valley end sealer or Anchorseal, then mill the logs.

Over the winter the moisture content drops to about 15%, and in the spring I move it indoors, still stickered until it reaches shop equilibrium.

I've used a microwave oven to dry bowls, it allows me to go from green to completed bowl in one day..........Rod.

I bet someone could answer this at Woodweb's sawing and drying forum
http://www.woodweb.com/cgi-bin/forums/sawdry.pl

As a woodturner, I have tried to dry rough turned bowls in a microwave, and have found it to be a sub-optimal method. Only one bowl can go into the microwave at a time. The energy level and time for cooking falls into the trial and error category. Unfortunately, when the error occurs, the bowl is cracked. The time in the microwave may only be 30 or 45 seconds, followed by allowing the piece to cool for a while, and then repeating the process for as many cycles as it takes to get the piece to a stable weight. A more effective method (for me) was to build a drying chamber where I could load numerous rough turned bowls, rectangular blocks (for pepper mills), and small slabs (14" x 10" x 1.5") at the same time. There is much information on-line about woodturners using old refridgerators or freezers as drying chambers. I chose to build my own so that I could size it to fit the available space. The box is about 5'H x 3'W x 2'D, and is insulated with foam board. The source of heat is an incandescent bulb. I increase the wattage each week for four weeks, using 40W, 60W, 75W, and 100W. The temp and relative humidity go from about 80 degrees and 80% RH when I start the cycle, to about 115 degrees and 15% RH at the end of four weeks. Air drying a rough turned bowl with a 1.25" wall thickness would take about a year. Thus, I have found this method to be very effective. If you want to see photos of my build, send me a PM and I will email you the photos.

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Originally Posted by Jason Buresh

Ok, let me start off by saying this is not a joke.

I was wondering if anyone has had any success drying slabs in the oven? I had a branch from a big silver maple in my yard come down after a big storm this weekend and I wanted to make some mini slabs instead of burning it or bringing it to the landfill.

What temperature do you set the oven to and how long do you bake it? I guess I could experiment but I always like to have a starting point. The slabs are maybe 12-14" long and maybe 6"-8" wide and I haven't cut them to thickness yet. I was going to try to make some lids for home made fly fishing boxes with the wood so I may start at 1"-1.5" and plane it down from there.

Thanks for the input!

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Oh boy... where to start.....

First - branch lumber is typically not milled into lumber due to the fact that severe stresses are present in the wood. The top side of a branch typically has cells that were in tension, and the bottom side of the branch has cells that were in compression, and when milled the lumber tends to distort greatly (to the point where 80% is unusable).

Second, drying lumber is not just about heating it. During the drying process three things play a factor in the drying rate. These are temperature, humidity, and air flow.

If you try to dry lumber too quickly, you will damage it severely (namely internal honeycomb / checking). RH% is something that needs to be closely controlled during accelerated drying, and you have no way to do that in an oven.

Yes, bowl turners will use an oven to dry their roughed out pieces, but these are pieces that have been turned down to 3/8” or so and you can safely accelerate the process on thin lumber.

Lumber dries very poorly in log form; the proper process is to mill and then dry.

Each species of lumber has a maximum safe daily drying rate. For 6/4 maple, you’re looking at around 5% or so max per day. Once you have dried below 25% MC it is difficult to damage the wood; however above 30% MC it’s fairly easy to damage (even though the damage usually does not become apparent until the wood is below 25%MC).