# Green wood chips



## jerrytheplater (Sep 16, 2017)

I'm new to this site and love the taste of smoked food. I have a few questions:

I can get a lot of wood chips free from a friend that owns a tree service company. We are thinking of using wood chips as a fund raiser for our outdoor youth organization, Trail Life USA. He will save large logs and chip them for us in his 130 HP chipper. He will give us what ever wood we ask for, as long as he gets it. I've already used apple and cherry from him, although I've dried it out in log form before cutting it into chunks. He can easily get hickory, maple, oak, apple, cherry, ash. We just need to tell him what to save for us.

We have not committed to this fund raiser yet and are still investigating it.

If we do get garbage can loads of green wood chips, I am thinking we will not be able to bag them up while green due to mold or fungus. How would you guys suggest we dry out the chips? We are not talking about multiple cubic foot quantities. We would be storing the chips in closed plastic garbage cans outdoors in an unheated detached garage.

Jerry Smith

Bloomingdale, NJ


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## dave schiller (Sep 16, 2017)

That will be a difficult task.  I'm not sure what you mean by storing them "outdoors in an unheated detached garage."  Outdoors or inside the garage?

Make sure you get the kind of wood chips you want, not mixed with other (perhaps undesirable) woods.  Most tree services blow everything into the truck, including the leaves.  As for drying, I guess the best way is to spread the chips thinly and evenly on the garage floor, then use a house fan to blow air over them.  In an unheated garage in your area in winter, it may take a long time.  You may need to do some culling of unsuitable material, as most chips I've seen from tree services vary in size and shape.

Overall, I don't think this will work.  I could be wrong and others may offer good advice.


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## jerrytheplater (Sep 16, 2017)

Hi Dave

Thanks for replying. Sorry for the confusion about how we will store the chips. We plan on placing the chips in covered garbage cans inside an unheated detached garage. I know there won't be any problem for the chips if they are dry. The problem is that they will be green when we get them.

Quality of the chips: The owner/operator of the tree service is a member of our Trail Life leadership. He plans on saving logs of wood of the type we want (which is being determined right now, I am doing the research and that is why I joined this forum. I am a novice smoker and have previously only used wood available in Home Depot etc. I just got a Brinkman electric smoker last year. I also use chips in my Weber kettle grill in foil packs or in metal trays.)

The plan is for the chipping to take place where the chips can be blown into a pile on a tarp with each wood kept separate. We would then collect what we need and load the rest into his truck for his normal process of dealing with the chips. We would have bark on the chips, but no leaves. He told me that he can handle up to 18-20" diameter logs. If he feeds them in with the diameter of the log going into the blades we will get the smallest chips. If he sends it in with the length of the log going into the blades, we will get larger chunks and pieces. I can see the need of screening the chips for size classification. I have various screens available from my gardening hobby where I screen my compost.

We have been thinking of drying the chips in ovens, but I am thinking the mother of the Trailman would not like that idea. I have no idea of what the smell would be like. I suppose commercial chip producers have a kiln or rotary drum dryer of some type to dry their chips. Or they season the logs prior to chipping. Our problem is wanting the chips to sell now and not having time to season the wood naturally.


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## dave schiller (Sep 16, 2017)

Jerry, if you can get the size of chips you want and all of the same kind of wood, that's good.  As for drying them, you're right; Mrs. Smoker would probably not appreciate her oven being used for such a project.
	

	
	
		
		



		
			






Perhaps you could use a 55 gal barrel or something, cut lots of small holes and a door in it and fabricate a frame to rotate it above a heat source.  That's a lot of work for such a project but once dry, the chips can be stored in sealed containers.

Best of luck in this worthy project.


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## gmc2003 (Sep 16, 2017)

Jerry, why not stay with chunks? If you really want to go the chip route maybe season the log then put it thru the chipper. 

Just a thought

Chris


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## jerrytheplater (Sep 16, 2017)

gmc2003 said:


> Jerry, why not stay with chunks? If you really want to go the chip route maybe season the log then put it thru the chipper.
> 
> Just a thought
> 
> Chris


Chris

I agree the seasoned log idea is best. And maybe he may have some. Then again, I know a second tree man that also stores logs for eventual splitting and sale as fire wood. So now I'll have to see if they have seasoned wood. That really would be best.

I'd love to stay with chunks. I like them better for the Brinkman. Not too sure what they would look like from the chipper. The ones I buy look like they are split. Do you know how they are made? I have cut chunks on a bandsaw at work, but that will take a lot of time that my employer would not appreciate. This project will use a lot more chunks/chips than I would ever need for my own personal use. 

Dave

Your idea sounds like a rotary kiln. I have steel drums available that used to contain 99% isopropyl alcohol, so they are clean to use. But the work involved to make it and the time over the fire may be prohibitive. We'd need a motor to rotate it, a frame to hold it, bearings so it would rotate. But, its in the back of my mind now. It is almost sounding like a compost tumbler. Do they make them in metal?

Jerry


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## dave schiller (Sep 17, 2017)

Jerry, I guess I was loosely describing a rotary kiln.  Hadn't thought of it that way.  So maybe you can find a compost tumbler that can be used or modified for your purpose.  I have no idea how long it will take to dry the chips, but probably not as long as it takes to season a 18-20" logs to get dry chips from the chipper.


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## cliffcarter (Sep 17, 2017)

Jerrytheplater said:


> If we do get garbage can loads of green wood chips, I am thinking we will not be able to bag them up while green due to mold or fungus. How would you guys suggest we dry out the chips? We are not talking about multiple cubic foot quantities. We would be storing the chips in closed plastic garbage cans outdoors in an unheated detached garage.
> 
> Jerry Smith
> 
> Bloomingdale, NJ


How to dry the chips- Spread them out on a tarp(black or brown colored if possible) in the sun, after 4 hours turn them as best you can with a shovel or rake and leave for another 4 hours. I would not be surprised if 8 hours is enough for wood chips. If you need you can repeat the process.

You should not store the chips in covered plastic garbage cans, IMHO you should store them in the garage on a tarp, not in a container, especially not an impermeable plastic one.


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## gmc2003 (Sep 17, 2017)

Jerry sorry I don't know how they are made in large quantities. I have a friend who's a logger if I can reach him I ask if he has any ideas.

Chris


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## jerrytheplater (Sep 18, 2017)

So I spoke to a few friends last night about this project. One that is a finish carpenter said it is estimated that wood dries one inch of thickness per year in a covered outdoor shed with plenty of spacing between the planks. (which is to say that it will take forever to dry a full sized log with the bark on.) Another said that it takes a full year to season wood properly stacked, shielded from the rain, and split for burning before it is seasoned. Another said he couldn't see anyone chipping seasoned firewood because it is so much more valuable as firewood than as chips. 

So, Cliff's tarp idea in the sun is sounding good. I am thinking the rotary kiln project is too hard to even consider. Another option is to try to bake them in outdoor gas grills in aluminum pans. 

I am going to do a test on some green chips in my electric convection oven at work, if it does not smell too much. It is not ventilated to the outdoors. It is vented to the second floor work area where five of us work. I want to see how long it takes before I don't get any further weight loss after heating at 350F in a glass baking dish.

Chris- no worries if you can't find out how commercial chunks are made.


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## dave schiller (Sep 18, 2017)

Jerry, I think 350F it too high.  Try about 200-205F.  Keep it below boiling.  At the higher temp, you may scorch the chips and cause a furor in your office.  Let us know how it works.


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## jerrytheplater (Sep 18, 2017)

I am thinking I'll just ask those in the area if they wouldn't mind the experiment. But I can't set off the smoke alarm either. That will call the FD, and that's a big no no.


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## jerrytheplater (Sep 19, 2017)

I was thinking a bit more about the temperature to dry the chips. Maybe low is the best way to avoid boiling off any volatile oils or other compounds that may contribute to the wood smoke flavor. I guess if I smell it, its not good. Thoughts?


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## cliffcarter (Sep 20, 2017)

Jerrytheplater said:


> I was thinking a bit more about the temperature to dry the chips. Maybe low is the best way to avoid boiling off any volatile oils or other compounds that may contribute to the wood smoke flavor. I guess if I smell it, its not good. Thoughts?


You're over thinking this is my thought. Dry them in the sun.


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## knuckle47 (Sep 24, 2017)

Good Morning,  I enjoyed the aquatic web pages.  Loved that stuff for years,in fact, there is still a 250 gallon plexi tank embedded in my wall.

I built a monster splitter to utilize my hurricane Sandy wood supply.  Most were 16-20" logs, split and dried over 2 years.  As oak splits, it shears off small chips and chunks all around the base of the log splitter.  It turned out to be 2 full 96 gallon trash cans with pieces as small as a finger and ranging up to 1/2" thick and 12" long.  So essentially all small thin and light.  

My FRUGAL side says you can't just rake this up and toss it. So just sitting in the plastic cans, it was thin and dried within a few short months with a fragrance of a new furniture store.

I have about a 5 gallon bucket left from mixing in with my gravity feed and the firebox of a 275 gal reverse flow.  Never presented an issue.  While spreading them out over so much real estate seems like intrusive work, try the compost tumbler or clean trash pails.  Production volumes might be tough if your storing indoors.  I just stuck mine behind some wood piles in the very rural area we live so it was not an eyesore ( not that I really care :) I do think they will dry faster than you may believe if you open the lid every so often, besides they not airtight anyway


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## jerrytheplater (Oct 10, 2017)

I was given about 15 gallons of Northern Red Oak chips from my friend last Friday night. He said they were from a dead tree. I sieved them through a one inch opening screen and removed the large pieces that were retained by that screen. I then sieved them in a 1/8" opening mesh and discarded everything that passed through it. (Actually added it to my Blueberry plants mulch.) I ended up with 10 gallons of size graded wood chips and about 2.5 gallons of large chips/chunks. The rest became mulch.

I brought some of them to work today. I placed them in a Pyrex 13" x 9" baking dish. I weighed the chips and came up with 1.44 lbs. I baked them in the oven at 100C from 9 AM to 4:30 PM and lost 0.22 lbs, which is a 15.3% weight loss so far. No odors at all. I have them baking overnight and will check in the morning if they've lost any more weight. Then the question will be, how much moisture will they re-absorb as they come to equilibrium with the environment? I guess it will not matter how much they absorb back again, because even commercial chips would have the same moisture content. My main concern with fresh chips is mold.

I did not try drying them on a tarp yet. They aren't green chips.

For those of you that say I'm overthinking this, I actually enjoy the experimenting.


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## dave schiller (Oct 11, 2017)

I've seen numerous questions asking how dry wood should be for use in a smoker.  I can't answer that because the answer varies.  Some of the experts tell us to use wood that is very dry, others say to use wood that is slightly to very wet.  But whatever wood you choose, here's some technical information on moisture content of wood.  To better understand wood moisture content, there are two principles that need to be examined.

First Principle - Moisture Content
Green, fresh, uncured, live wood has a lot of water in it.  Often there is more water (by weight) than there is dry wood.  For example, a piece of wood might weigh ten pounds when wet, but only four pounds when thoroughly dry.  Using the following formula to calculate wood moisture content, that piece of wood originally had a moisture content of 150%.

Moisture Content (mc) = (Initial Weight - Dry Weight) / Dry Weight * 100
Or
150% =  (10-4)/4 *100
There were initially six pounds of water and four pounds of wood.

The mc of wood can be determined by two methods.  The simplest way is to purchase and use a moisture meter.  They are inexpensive, reasonably accurate, and are widely available in big box stores and online.  Prices range from ~$15 to hundreds of $.  Just turn it on, stick the prongs into the wood, and read the mc.

To absolutely determine wood mc, take a small to medium size piece of wood (green or partially cured) and weigh it accurately.  I use a kitchen digital scale set to grams.  After weighing the wood, place in it your kitchen oven in the convection (fan) mode set to about 200F.  The oven fan circulates and vents the air, removing the moisture.  After a period of time, weigh the wood again and put it back in the oven.  Then weigh it again later and repeat the process until the wood reaches a constant weight.  That is, no more moisture is being driven off.  Then it's mc is assumed to be 0%.  This may take several hours.  Use the initial weight and the oven dry weight to determine what the mc of the wood WAS.

This method is impractical if not impossible to use for large pieces or quantities, so use the moisture meter for typical measurements.  Oven drying wood is a good method to calibrate your hand-held moisture meter if you measured the mc prior to drying the wood.  Compare the readings of the meter and the original mc of the wood.  I use a piece that initially weighs about 100-200 grams.  Large pieces may take a long time to dry, so it's not a practical bulk drying method.  Air drying is the common way to dry wood.

Air-dried wood is usually  drier on the surface than in the middle, so a meter reading of 15% on the outside may not reflect the mc of the middle.  Only after a long time (months, a year) the wood should be equally dry all the way through.

So, how long does it take to dry (cure) wood?  The answer depends.  Doesn't everything?  It depends on the temperature and humidity of the air and the size of the pieces.  The drier and warmer the air, the faster the cure.  Smaller pieces dry faster and air circulation helps speed the process.  The general rule is that it takes hardwoods about a year per inch of wood thickness.

Second Principle - Equilibrium Moisture Content
The moisture content of wood depends on the relative humidity and temperature of the air surrounding it.  If wood remains long enough in air where the relative humidity and temperature remain constant, the moisture content will reach constant mc at a value known as the equilibrium moisture content (EMC).  However, wood is like a sponge.  If it reaches the EMC of, say, 12% under constant temperature and humidity and the conditions become more humid, the wood will absorb moisture and reach a higher EMC.

The EMC of wood can be calculated by using the information in this link:
http://www.csgnetwork.com/emctablecalc.html

Or you can get a general estimate for your area from the table in the link:
https://www.fpl.fs.fed.us/documnts/fplrn/fplrn268.pdf

These data assume that the wood is stored outside in ambient conditions.

Kiln dried lumber is usually dried to 6-8% moisture content.   If the humidity is high and storage time is long enough, the wood will increase in moisture content, which can create problems in product manufacture or performance of an end product such as furniture and cabinet making. There are several ways to minimize this problem, including wrapping the lumber in a moisture barrier or store it in very dry conditions.  For firewood, this is unimportant.

So if you live in hot, dry Las Vegas, the EMC of your wood can reach 4.0% during summer (from the table in the link).  Conversely, if you live in cool, damp Seattle, the lowest EMC is about 12%.  No further curing time will make it drier.

To check the validity of the calculator, I measured the temperature and relative humidity of my basement.  It's pretty dry down there and the temperature is fairly constant and has been for years.  I measured 60% humidity and 75F.  That calculates to 10.9%.  Then I measured the actual mc of several exposed studs with my moisture meter and came up with 9-11% mc.  That's a reasonable reading under those conditions and represents what I can expect my drying firewood to be when fully cured (in the basement).

So when you're curing wood, don’t expect the mc to vary much from what the calculator or table says.  After it reaches its EMC, it won't go much lower or higher.


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