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View Full Version : "Reading a Log" question for experience sawyers



David Mealey
03-07-2017, 2:07 PM
I've posted in the recent past about my steep learning curve on an old hydraulic Mizer LT40. I can report that I took the suggestions provided and took a lesson with the local Mizer dealer. The lesson helped with the mechanics of the mill but unfortunately the guy teaching didn't have much experience with sawing real trees. Good news is I've been getting some experience on cherry and alder logs and getting comfortable with what the mill can and can't do.

My question for you old timers is what do you look for in the log when setting it up for milling? Quarter sawing aside, what should I be looking at when sawing for quantity vs. quality of say, a 5/4 board? I know that getting the log level to the bed relative to the pith is important, but how do you decide on which side of the log to cut first and how do you proceed from there? How do you "read the log"?

Thanks for you input!

David M.

david privett
03-07-2017, 5:23 PM
well I look to see if there is a hook in the log I can work out because they usually will wrap somewhere after being cut as they can be a stressed wood. Large forked places where branches come out can be a issue also for splitting . they might try to be avoided also. But when I cut I have to ask myself do I want the most of what the log will offer or it there a specific board size I am looking for. Usually it is the latter so there is some more waste.

Alex Snyder
03-08-2017, 7:14 AM
Is the log straight? That's the first thing. If it something rare, and you've got to deal with some weird growth, then saw off as much excess as possible with the chainsaw to inspect grain patterns. That might help to better identify the things David is referring to.

Because I mill for myself, and burn firewood, waste isn't a huge concern. Like David I'm usually cutting for a specific project.

As far as where to cut first, I generally start on the side that is least parallel to the opposite side and then repeat the same with a 90 degree turn of the log. It may create 2 or 3 large waste cuts, but it gets you cutting useable boards faster.

Scott T Smith
03-08-2017, 10:32 AM
David, log setup and choice of initial face to mill usually results in different approaches if you are milling for grade, milling for yield, or quartersawing. For the sake of this response, I'll presume that you are interested in milling for grade.

When milling for grade, it's best to position any defects in the log so that they will be at the edges of the board. That way they can be edged off and you can still net a FAS grade board.

Usually when grade milling you open up the best face first, and mill boards from it until the grade starts to drop off. Then you turn the log to the second best face and repeat. This is presuming that you have an edger that makes it easy to edge live edge boards. This technique allows you to yield the greatest quantity of wide, grade lumber from the log. Additionally, typically grade lumber is milled parallel to the bark, as opposed to parallel to the pith. This results in minimal slope of grain on the edges of the board, but leaves you with a wedge shaped discard with the pith in it when you are done milling.

If you don't have an edger, then set up your log so that the defects are located on the corners of the cant, and alternatively grouped together in as few of faces as possible. Then mill the best face until grade drops off and turn to the second best face, etc.

Some logs that have a lot of tension in the sapwood will require you to square up to a cant in order to get rid of the sapwood stresses before milling the boards.

As far as determining defects in the log, look for stain on the ends, bumps on the surface of the log or obvious limb locations, sweep in the log or pith that is more than 15% off center. These are all indicators that the boards from the associated faces will be lower quality.

David Mealey
03-08-2017, 8:19 PM
David, log setup and choice of initial face to mill usually results in different approaches if you are milling for grade, milling for yield, or quartersawing. For the sake of this response, I'll presume that you are interested in milling for grade.

When milling for grade, it's best to position any defects in the log so that they will be at the edges of the board. That way they can be edged off and you can still net a FAS grade board.

Usually when grade milling you open up the best face first, and mill boards from it until the grade starts to drop off. Then you turn the log to the second best face and repeat. This is presuming that you have an edger that makes it easy to edge live edge boards. This technique allows you to yield the greatest quantity of wide, grade lumber from the log. Additionally, typically grade lumber is milled parallel to the bark, as opposed to parallel to the pith. This results in minimal slope of grain on the edges of the board, but leaves you with a wedge shaped discard with the pith in it when you are done milling.

If you don't have an edger, then set up your log so that the defects are located on the corners of the cant, and alternatively grouped together in as few of faces as possible. Then mill the best face until grade drops off and turn to the second best face, etc.

Some logs that have a lot of tension in the sapwood will require you to square up to a cant in order to get rid of the sapwood stresses before milling the boards.

As far as determining defects in the log, look for stain on the ends, bumps on the surface of the log or obvious limb locations, sweep in the log or pith that is more than 15% off center. These are all indicators that the boards from the associated faces will be lower quality.

Thanks for the thoughtful response Scott. What do you mean by "milling parallel to the bark". I'm guessing that means looking at the direction of the grain and positioning the log on the bed to get to get as close to rift sawing or even quarter sawing as much as possible throughout the board?

Took the time to look at your website and was impressed with your operation. Being a small fry "wanna be", I don't have an edger/large planer but I've seen some sawyers turn the boards on their side and create an edge right on the mill. On easy to handle boards have used my 8" jointer to get a straight edge. Will that suffice for "edging"?

DM

Tom Hogard
03-09-2017, 11:17 PM
David,

As you have read, there are different approaches depending on what you, or your client, wants to get from the log. I get frequent requests for 8/4 live-edged planks - destined for benches or tabletops. Last summer I shot a video explaining what I look for, and I mill the log to get it. Here is a link https://youtu.be/uhJnuWPLfKk

Alex Snyder
03-10-2017, 6:28 AM
Here is a link https://youtu.be/uhJnuWPLfKk

You've gained a new subscriber here. Thanks Tom!

David Mealey
03-10-2017, 6:18 PM
David,

As you have read, there are different approaches depending on what you, or your client, wants to get from the log. I get frequent requests for 8/4 live-edged planks - destined for benches or tabletops. Last summer I shot a video explaining what I look for, and I mill the log to get it. Here is a link https://youtu.be/uhJnuWPLfKk

Great video Tom,

You've gained another subscriber. Whats the cutting width on your Timber King? Did you make the 8/4 jig?

Scott T Smith
03-10-2017, 6:52 PM
Thanks for the thoughtful response Scott. What do you mean by "milling parallel to the bark". I'm guessing that means looking at the direction of the grain and positioning the log on the bed to get to get as close to rift sawing or even quarter sawing as much as possible throughout the board?

Took the time to look at your website and was impressed with your operation. Being a small fry "wanna be", I don't have an edger/large planer but I've seen some sawyers turn the boards on their side and create an edge right on the mill. On easy to handle boards have used my 8" jointer to get a straight edge. Will that suffice for "edging"?

DM


David, the term "milling parallel to the bark" means that you raise the narrow end of the log until the top of the log is parallel to the blade path on your mill. The initial slab off-cuts will be the same thickness end to end, instead of tapered when you set up parallel to the pith.

Let's say that you are milling a log that has a large end diameter of 18", and a small end diameter of 16" (2" taper). To mill "parallel to the bark" you would use your toeboard to raise the small end of the log 2", so that the top side of the log is parallel to the blade path and bed of the mill.

Typically if a sawyer does not have an edger they will edge on the mill. It's effective - just time consuming. You don't want to use your jointer to edge with because bark is hard on blades and knives and if you run a bark edge across a jointer it will significantly accelerate the dulling of your knives or cutters.

Tom Hogard
03-12-2017, 12:49 AM
My Timberking B-20 has a max cut width of about 23.5" (the newer models go to 33" or so). That is why I try to find the best book-match when milling for tabletops. I made several of the jigs. When cutting for myself I get me start heights from a phone app and do the heart-centered part in my head but when working with a client, the jigs are quite helpful in showing what, and why, I am making a cut at a certain location. I have them for 6/4, 8/4, 9/4, and 10/4 - the most common thicknesses I get requests for. Each jig has a different thickness on each side, made out of Plexiglas.