Kiln Drying Oak Firewood

[@BW35bucket]

Great video Matt. I know all about being busy. That’s Awesome you have a busy schedule. You’re having a successful business. Hang in there. Video here in there no biggy. Be safe sir.

[@Treestofirewood]

Thank you. Yeah crazy. Ultimate goal is to be safe. Hope you’re doing well also.

[@joekrzeminski467]

Nice to have you back Matt. Great update.

[@Treestofirewood]

It’s good to be back. Everyday I want to make some videos. Just so tired. But I’m going to make it happen at least 3-4 videos a week. That’s my goal at least.

[@richarddabkowski2896]

Looks like oak has lived up to its notoriety

[@Treestofirewood]

Oh 100% is. I definitely didn’t think it would take this long. I figured a few more days but not another week. Haha.

[@CouncilHill-zz3pu]

Couple feedback thoughts, take them for what they are worth…..they come from a guy with some lumber kiln drying experience and who is building another wood boiler heated kiln for firewood. (Thanks for sharing your build by the way, it’s been very helpful). Maximizing airflow through the wood is important. In my kilns I’ve followed the Nyle design of hanging fans in a lengthwise baffle from the ceiling. Air moves through the fan to the wall and down through the wood (either stickered- lumber or in totes - firewood) in a circular manner. To that end would loose thrown firewood in totes work better than tight stacked. Obviously you lose volume but you might gain overall efficiency. In the beginning of a cycle I’m inclined to build as much heat as possible, get the air as humid as possible, vent it quickly, then cycle again, thinking that the constant introduction of fresh air means heat loss and to some degree introduction of ambient humidity in the later stages. I try to get to as close to 100% humidity and do a full volume dump vent of the whole kiln and then stop and repeat. Of course pushing to fast can lead to case hardening and making migration of internal moisture out even more difficult. To that end, when I find that I have surface MC% in the 20’s inevitably splitting a big piece shows the internal moisture is much higher. I agree with your thoughts on pre drying or air drying for a week or more before going to the kiln. I also find smaller spits helpful of course. Thank you for allowing me to share, best of luck to you. Chris

[@Treestofirewood]

Chris. Thanks for sharing. All good valid points. How hot do you get your kiln up to? I’ve never let my moisture get past 60ish%. But I could try it. You have given me some good ideas to think about. I feel my results are really good when I’m not drying oak. I knew this wood was going to be a different animal. I will see what I come up with and give it a shot.

[@CouncilHill-zz3pu]

@@Treestofirewood For firewood I’ve been letting it run as hot as it can, but with the boiler alone I can’t get past 155. I’ve seen guys add wood stoves in side compartments of their kilns to get them hotter. For me it’s more about the RH. 140 degrees will generate a lot of humidity early in the cycle. So I let the humidity build in the air as high as it will go, then I dump that air and start building again. My circulation fans are high velocity but not that much volume. My vent fans are bigger and dump the kiln box pretty fast. But I’m learning to about venting. I’ve been watching your videos trying to pick up new ideas. My lumber kilns were all dehumidification kilns and with them the water was drained as a liquid, the box didn’t get vented so I’m fumbling my way into what works best.

[@Treestofirewood]

@CouncilHill-zz3pu I normally slowly vent non stop to keep temp up and moisture up enough to keep the wood wet enough to not case harden. Like I said mixed hardwoods 5 days. But this oak I think I put in too early. The next batch will have been air drying for 2 weeks at least I feel will be much better for drying times. I will fully document what I do on that load.

[@lyleharkness-rv5vf]

Good to see you again. I can only imagine how busy you have been with all the severe storms we have had this year. Have you ever had a problem with case harding your kilned wood. I don't have experience with kiln drying firewood, but we had to be careful rising the temperature to quickly. Good update 👍

[@Treestofirewood]

Yeah we have been pretty busy this year. Storm damage has finally slowed down. I have t had case gardening since the beginning. I leave the moisture high for the first few days to try and prevent that from happening. Seems to work pretty well.

[@lyleharkness-rv5vf]

@@Treestofirewood we had an exhaust fan malfunction and it turned ash into harder than oak with a higher internal moisture content than external. Couldn't work it with high speed steel. Congrats on avoiding that mess.

[@Treestofirewood]

@lyleharkness-rv5vf how hot can you get your kiln? And how slow do you bring up the temperature?

[@lyleharkness-rv5vf]

@@Treestofirewood top out at 160 depending on species, lumber kiln not firewood. Usually it takes a week to get up to temperature, depending on the initial temperature. Summertime it can be as little as three days, winter with cold lumber sometimes as long as 8-9. We have to put weights on top of the stacks because the movement of the wood as it dry.

[@ryangoff8853]

I had the exact same experience trying to dry oak in my copycat kiln. It takes forever. I thought I was doing something wrong

[@Treestofirewood]

Yeah it’s crazy. Now that my oak has been air drying for a bit. I’m down to 10 days or less. Plus I made some kiln modifications to speed up the process. It’s working quite well.

[@donmcgimpsey1706]

Oak is always the time sink. Only dries at 1 inch per year - split! do you season any wood at all, or is it all kiln?

[@Treestofirewood]

I do season wood. But these last few years my demand has just grown 10 fold and I’m just trying to keep up. That’s why I have had my kiln running non stop since this past December. My goal this winter is to get way ahead so I can season 70% of the wood I sell and then start drying wood in the kiln this time next year. This winter I’m going to try and have around 500 full cords split and stacked by March so I’m ahead. We will see how it goes.

[@buckinfirewood]

Why 20?? Why not 40?? That new boiler should be able to heat er up no problem..

[@Treestofirewood]

Oh I know she could heat it up with out a problem. But I feel to be able to get enough airflow I would still go down the middle of the kiln and leave the sides open. Heating is not the issue. It’s about airflow and being able to keep the heat in and extract the moisture all at the right times. I have it down pretty good but all this humidity we have right now sure isn’t helping.