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Marc Lapointe
11-30-2017, 11:42 AM
Looking for some experts on what I should do with this burl. The tree is still up as shown. I want to dry it properly. Probably going to want to get 2" slabs out of it. Cut first then dry? Dry then cut? Looking for guidance!

Thanks
Marc

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Kevin Jenness
11-30-2017, 12:03 PM
If you are going to slice it up, do that first as the pieces will dry faster with less checking.

John K Jordan
11-30-2017, 12:28 PM
If you are going to slice it up, do that first as the pieces will dry faster with less checking.

Absolutely, a large chunk of wood will take many years to dry, maybe decades.

I would slab it, remove as much of the unwanted bark and wood as possible, then coat with Anchorseal. Normally we just coat the end grain but since burl usually has grain running every which way I just coat it all the way around. I have some 3" thick pieces like that on my shelves now I'll let dry for maybe 3-5 years then scrap off some of the wax and let it dry 3-5 more years. (I like to turn dry wood.)

JKJ

Lasse Hilbrandt
11-30-2017, 2:02 PM
Definitely cut first because burls dry very slow. I have a large oak burl I have cut into slabs and I have not done anything else to it and it dries nicely without many cracks.

david privett
12-01-2017, 8:53 AM
you might want to try to take a chainsaw and cut threw the sap layer around the tree killing it but leave it stand for as long as you can before insects attack it to much and let gravity help drain the fluids out of the tree. When I can I saw recent standing dead trees and it makes things easier on several ways.

John K Jordan
12-01-2017, 9:11 AM
you might want to try to take a chainsaw and cut threw the sap layer around the tree killing it but leave it stand for as long as you can before insects attack it to much and let gravity help drain the fluids out of the tree. When I can I saw recent standing dead trees and it makes things easier on several ways.

I read once that tropical trees are sometimes harvested by girdling. I've had some standing dead trees here on the farm that ended up being some very stable turning stock. A machete, axe, or hatchet works too.

There is another way sometimes recommended for drying slabs at the sawmill: cut it down then stand the log vertical but off the ground - the free water gushes out, especially for some species! (The bound water, not even.) I've done the vertical thing after sawing for thick slabs - let them drain for a few days until they stop dripping then sticker to dry. Can apply something like timbor to keep out the insects but that's not much of a problem in the winter (the best time anyway since the sap is down) and not a particular problem for some species if kept from touching the ground.

Hey, I may have missed it but I didn't see mentioned what kind of wood it is.

JKJ

Marc Lapointe
12-01-2017, 10:19 AM
Thanks for all the input.

I'm going back out to inspect it tomorrow, didn't have more time than to take the picture before. It is either oak or maple but I'm going to say more likely oak.

I did a bit more research and here's the plan so far:


1. Cut from tree leaving 6" above and below the burl. I could stand it up here and let it drip but I don't expect much would happen.
2. Bring to a mill and cut 2" slabs in the direction of the tree growth starting with the tree side and working my way down to the outside of the burl
3. Put on Anchorseal, both sides.
4. Stack. sticker and weigh it down, maybe even strap around it to prevent as much warping as possible

Remaining questions

Store in my shed, outdoors/covered or my basement? I'm in New Hampshire so some humidity in the summer. Shed will get hot too (like 100+F at times).

If you look closely at the picture, it is very smooth on the outside, not all knarly like most burls. With this in mind, is it more likely to have relatively standard grain or could it still be very figured?

I plan to cut it down this weekend. Not sure how long before I can get it to the mill (hopefully withing a week or so). Is there a time concern with getting it to the mill and also getting it Anchorsealed after the cut?

Thanks
Marc

John K Jordan
12-01-2017, 2:35 PM
...Store in my shed, outdoors/covered or my basement?
...Is there a time concern with getting it to the mill and also getting it Anchorsealed after the cut?


You can never perfectly predict what is inside a burl. Some (unlikely with yours) are simply a bulge where the tree healed around a broken off branch - worthess with bark and rot inside. Some have bark inclusions, nests of black ants, rot, and who knows what else. Some the figure is fantastic; some boring. The only thing I know is to cut it and see. Just be prepared to be disappointed or excited. When I saw logs on my mill it is always fun to see what the cuts will uncover!

This time of year it doesn't matter much where you store it as long as you keep it off the ground. If covered with a tarp, don't wrap tightly which will prevent air circulation or the wood may start to rot. Inside in a heated space with low humidity is sometimes hard on wood since it can cause it to dry too fast and crack, even with wax.

A shed is usually good except for a hot shed in the summer. I dry chunks from burls and turning stock indoors on wire racks. (My shop has heat and AC.)

When I air dry lumber and slabs I cut on my sawmill it is always outdoors, stickered. I make a good base with concrete blocks and some long horizontal boards, then lay down stickers (1"x1" sticks), put down the first board and put stickers on top, then repeat. Cover with something to keep the sun and rain off. The air should be able to freely circulate through the sides. There is a lot of information about this on the internet or get a book to learn about drying and wood movement. Understanding Wood by R. Bruce Hoadley is my favorite.

Burls don't usually warp like lumber because the twisty grain inside removes some of the reason wood warps as it dries. They will still crack.

It is always good to Anchorseal fairly soon after cutting. Some wood will start to check and crack very quickly, especially in the summer. If the weather is cool a couple of weeks shouldn't make any difference, especially if the end grain is sealed and the wood is kept off the ground and in the shade.

JKJ

Larry Edgerton
12-02-2017, 6:21 AM
you might want to try to take a chainsaw and cut threw the sap layer around the tree killing it but leave it stand for as long as you can before insects attack it to much and let gravity help drain the fluids out of the tree. When I can I saw recent standing dead trees and it makes things easier on several ways.

Kinda like that, but my method is wait till spring until the buds have opened

Then cut the tree. The leaves will continue to bloom drawing moisture. You have to wait until they are just recognizable as leaves, too soon and the will not continue. You can either girdle the tree or cut it but do not cut the tops off until the leaves have bloomed, dried up and blown away.

Marc Lapointe
12-04-2017, 2:33 PM
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Kinda like that, but my method is wait till spring until the buds have opened Then cut the tree. The leaves will continue to bloom drawing moisture. You have to wait until they are just recognizable as leaves, too soon and the will not continue. You can either girdle the tree or cut it but do not cut the tops off until the leaves have bloomed, dried up and blown away.</p>
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Larry, Do you thinki it is a big benefit in drying time to do this?&nbsp; I&#39;m not really in any hurry to use the wood. Even though it is on family property, it is far enough away from us yet close to bordering property that I would hate to see it disappear. Id rather cut it up now and let it dry for 2 or 3 years. Speaking of cutting it up, I took some more pictures and measured it. 30in across and probably 20in from front to where it stops wrapping around the trunk. Welcome any thoughts on how to go about cutting it given these added views. My plan right now is to set it up on the mill with the burl on the bottom and the trunk on top and make a cut an inch or so below where the burl wraps around so I can see what it looks like. Two options at this point. If it looks reall good, start taking 2in-2 1/2in cuts until I am through or if its not that great looking, make the next cut at the bottom of the trunk and cut the side lobes, for lack of a better term, as one piece on each side. They would end up 10 x 6 x 6 or so. Thanks Marc PS if there is a better forum topic where I ccould ask these questions, let me know. Seemed like this was the best WRT the drying</p>

Scott T Smith
12-07-2017, 12:29 AM
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</p>
<p>
Larry, Do you thinki it is a big benefit in drying time to do this?&nbsp; I&#39;m not really in any hurry to use the wood. Even though it is on family property, it is far enough away from us yet close to bordering property that I would hate to see it disappear. Id rather cut it up now and let it dry for 2 or 3 years. Speaking of cutting it up, I took some more pictures and measured it. 30in across and probably 20in from front to where it stops wrapping around the trunk. Welcome any thoughts on how to go about cutting it given these added views. My plan right now is to set it up on the mill with the burl on the bottom and the trunk on top and make a cut an inch or so below where the burl wraps around so I can see what it looks like. Two options at this point. If it looks reall good, start taking 2in-2 1/2in cuts until I am through or if its not that great looking, make the next cut at the bottom of the trunk and cut the side lobes, for lack of a better term, as one piece on each side. They would end up 10 x 6 x 6 or so. Thanks Marc PS if there is a better forum topic where I ccould ask these questions, let me know. Seemed like this was the best WRT the drying</p>

Larry, your milling concept won’t work because you cannot support the log with the burl on the bottom, nor would the sawmill head clear the log.

Your best bet is to clamp the log on the mill with the burl on the upper side, and then start slicing from the outside in. You will get some movement in the slices as they dry, so be sure to mill about 1/2” thicker than your desired finished thickness (presuming 8/4). I would leave them live edge on the outside. Personally I would not apply anchorseal to the burl slices, but I would stack, sticker, weight and cover outdoors for at least 2 -3 years for 8/4 oak burl slabs. Drying under an open sided shelter outdoors is best. After 3 years you can sterilize the slabs in a kiln.

Marc Lapointe
12-07-2017, 9:19 AM
Scott,

Larry suggested waiting til spring. I'm the one who detailed my plans for cutting the burl from trunk down rather than what you suggest. I pictured setting up some sort of craddle for it but need tot talk to the guy with the mill before any final plan is set. Also, I have no access to a kiln. I was thinking of putting it in my basement for 2-3 years. Not much airflow but controlled temps in the 60s. It's cut down as of yesterday so just need to get it cut up and stored away somewhere for drying

Scott T Smith
12-07-2017, 10:15 AM
Scott,

Larry suggested waiting til spring. I'm the one who detailed my plans for cutting the burl from trunk down rather than what you suggest. I pictured setting up some sort of craddle for it but need tot talk to the guy with the mill before any final plan is set. Also, I have no access to a kiln. I was thinking of putting it in my basement for 2-3 years. Not much airflow but controlled temps in the 60s. It's cut down as of yesterday so just need to get it cut up and stored away somewhere for drying

Personally I would not wait.

Wood dries best in lumber form - not in log form. While Larry's method to girdle a tree is a very good one, as he stated it's best to do so in the early spring when the capillary action from the canopy is best. The drawback to this timing is that the sugars are higher in the sap during the spring, and while you're waiting for the moisture content to drop you may encourage insect attacks or stain due to the high sugar.

Lumber weighs the same year round, but the sugar content in the sap is lower in the winter. Sugar contents are directly linked to the decay rate of the wood, so there are benefits to harvesting some stain prone or high value logs in the winter as opposed to the summer.

In general, the decay rate is much greater in the log than in the board. Decay is not just from insects and rot, but also because the log will dry from the outside in and you will experience shrinkage as it dries. When the shell dries faster than the core, surface checks are a result. Thus by waiting to mill you gain little and risk much.

Burled wood should be dried at a slower rate than normal because of the varying grain direction. The problem with putting it in your basement is that you risk mold and stain developing on the lumber due to lack of airflow. Drying involves three events - control of temperature, relative humidity and airflow. You would be better off to sticker it out doors but under cover for at least 6 months so as to allow the shell of the lumber to start to dry. Once the shell has dried down a bit you can move it into the basement and not have to worry as much about mold. If you have not option other than basement drying, I would suggest a box fan on low placed about 10' away from the stack to provide a steady but very slow airflow across the stacked lumber. Be sure that your stacked lumber is far enough away from a wall to allow air through the stack to escape. You may have a problem with RH% increasing in the rest of the basement though.

There is another benefit from milling now and not waiting. Drying outdoors occurs at a much slower rate in the winter versus the summer. If you wait you will be starting the drying process at a time when it's naturally faster, which is not the best choice for a burl.

Logs encounter a lot of force from the blade cutting action trying to move or deflect them. They also have a fixed amount of height that the head will rise (typically 24" - 28" maximum blade height above the bed depending upon the mill), and a fixed amount of space above the blade for the log. I can see no benefit from placing the burl down and a lot of drawback - especially when considering that the lumber produced would be the exact same burl down or burl up.

If your burl is white oak, below is an example of what the slices may look like. These are some that I dried and sold a few years back. The surface was sprayed with mineral spirits in order to show the grain.

Best of success to you.


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Marc Lapointe
12-07-2017, 10:31 AM
Thanks Scott. I hope to get it milled in the next week at the most and I will get it set up outside.
This is red oak. Pic is after it was cut

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Scott T Smith
12-07-2017, 10:36 AM
Thanks Scott. I hope to get it milled in the next week at the most and I will get it set up outside.
This is red oak. Pic is after it was cut

373148

Ought to be interesting inside. What are you planning to make from the lumber?

Marc Lapointe
12-07-2017, 11:26 AM
Ought to be interesting inside. What are you planning to make from the lumber?

All depends on what it looks like inside of course but I'm hoping to get a couple round end tables, some cribbage boards with the side parts of the the burl and although I don't have a lot of experience in turning , maybe a couple bowls

Scott T Smith
12-08-2017, 10:37 PM
All depends on what it looks like inside of course but I'm hoping to get a couple round end tables, some cribbage boards with the side parts of the the burl and although I don't have a lot of experience in turning , maybe a couple bowls

Whichever lumber you wish to use for turning blanks, coat all sides with 2-3 coats of Anchorseal Classic.

Marc Lapointe
12-17-2017, 9:19 PM
Finally got this cut into slabs. As we got close to the trunk it was pretty nice still so we made a couple more cuts and the entire thing is in slabs now.

I have it in my basement and will put some anchorseal on it in the next couple days and then stack and sticker outside. Here's a few pictures

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Scott T Smith
12-19-2017, 12:56 AM
Unfortunately that does not show grain pattern that is reminiscent of a burl. More likely a scarred over section where a limb was.

I’ve encountered similar situations many times when milling.

Marc Lapointe
12-19-2017, 8:37 AM
Unfortunately that does not show grain pattern that is reminiscent of a burl. More likely a scarred over section where a limb was.

IÂ’ve encountered similar situations many times when milling.

It definitely looks like an over zealous repair job based on the knot in the last picture that looks to be the center of it all. Still pretty unique grain pattern and I'll make something out of it when the time comes.