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Let's Talk Sawing!!

Started by Randy, February 27, 2005, 08:54:28 PM

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Randy

Since I got my trailer set-up to haul logs, I have picked-up around 30 pine logs. My question to All Of You PRO"s is this---If I am sawing these for myself to air dry till I decide what size boards I want to cut out of them------------What size should I cut them.  OK---------If I lost you----I read from alot of post on here that after the boards dry, some of you restack them back on the mill and re-cut them to the size you want and/ or also to get the bow out of them.  So I am thinking ???, for my 2x---------instead of cutting 2x4's why not cut 2x8's or 2x12's then when they dry, put them back on the mill and cut them into 2x4's or 2x6's if that is what I need----------how about cutting into 3x or 4x then resaw into 1x or 2x after they dry(I realize it will take longer to dry the thicker boards. I am new at sawing as you know so I would like to hear from you all on this. I sawed some 2x10's about 3 months ago and some 2x4's at the same time. The 2x10 dried so straight that I was shocked, about a third of the 2x4's bowed, some so bad I might could get into the Bow making business, but they were cut from 2 different tree's.(Had alot of weight on each pile) I cut some 2x6's and most of they dried fairly straight. I resawed some of the 2x6's into 1x6's and they turned out good. OK--FEED-BACK-Tell me what you Pro's do!! Randy

Tom

Randy,
In most instances you are better off to cut what you want the first pass.  If you later need a 2x4 and happen to have a 2x12 laying around that you don't need, then one of the three 2x4's that you get might be alright. 

Your 2x10 was probably straight because you had the heart centered by default and the tension was equalized on either side which stopped the crook.  It may have been cut from closer to the center of the log which would minimize the bow.

Your crooked 2x4's were probably cut from one side of the heart, in effect, imitating the same thing as splitting a 2x8.   

There are times when you can't help creating a board or piece of lumber with the grain not being optimal, but why put yourself in a position of creating secondary grain orientation when a little planning will allow you to keep your lumber prime?

A second reason to "not" resaw later is that dry wood cuts much harder on a sawmill then the green lumber the mill was designed to cut.   The second time around will be a much more difficult job than if you had taken care of it when the cant was green.

If you decide to resaw 2" into 1" boards, etc., think about getting a resaw.  They are designed to keep pressure on the board so that the blade remains in the middle.  You will not be so lucky as to have all of your boards dry as straight as the 2x10 you mention, yet, your sawmill will be cutting in a straight line.   I don't think you will be pleased overall.

If you are determined, then, a 4x12 cut from the center of a log will probably produce better 2x4's than a split 2x8, cut from anywhere in the log, will produce.

Randy

Thanks Tom, but let me ask this--------If I am air stacking 2x4's and notice they already have a bow in them right after cutting, if I stacked them on their edge, bow up, and weighted them down, Would this HELP in them drying straighter than flat air stacking them?? Thanks Randy

Tom

Yes it probably would.  I have customer that stack 2x4 studs on their 2" side to make them be straighter.   

Here is a hint that might work too.  Rather than turn the bow up, turn the bow down.  Let the ends of the lumber lift off of the stack and it will be easier to straighten the board.  If the bow is turned up it forms a bridge and that arch is a strong.

In this case we are probably talking more accurately of "crook" (side bend)

Dan_Shade

What's the normal method for taking off slabs to make a cant?

just get the biggest square you can get out of the log and throw away the rest or saw down as in through and through until you get to the square part?

Woodmizer LT40HDG25 / Stihl 066 alaskan
lots of dull bands and chains

There's a fine line between turning firewood into beautiful things and beautiful things into firewood.

Tom

There are as many ways of opening a log as there are sawyers. :D

I think that one should have in mind what he wants from the log before he starts.  That can change as you discover what is inside.  Procedures can be different depending on what you are looking for, too.

Here is one way for a bandsaw:

put the log on the mill so that the saw enters the little end.
Turn the log so that the heart crack is vertical.
level the center of the log to the bed
Open a "face" on the top of the log that is the width of the board you wish to produce.
Drop down and remove that flitch which will become that first board.
Spotting a target depth, continue to remove flitches until you reach it. (you are aiming to keep the pith in the center of cant, which will keep the grain centered in the boards)
Turn the cant 180 degrees and put the flat side down on the bed.
Do the same thing to the other side until you reach your target.  (having reached your target on both sides will leave you with a cant that is the width of the boards you wish to remove.)

Turn the cant 90 degrees and put the  cant flat against the squaring dogs.
level the center of the cant to the bed.
open a face on the cant.
remove the flitch.
continue cutting until the cant bows or you approach the pith

Turn the cant 180 degrees and put the flat face down on the mill It will be more stable now.
begin cutting from the top down until you have turned the entire cant into boards.

Pay attention to the air gap beneath the cant.  If the cant is bowing because of tension, the gap will widen and the  cant can be turned 180 to relieve the tension.

----------------------------------
That's one way. 
sawing for grade may have you leveling the top of the log rather than the pith and taking the leveling cut out of the center of the log.

Quarter sawing may lead you to cut a log into thirds or more and then cut these large flitches to get boards.

You may modify your approach depending on the size of the boards or timbers you are removing.
You may modify your approach depending on whether you are grade sawing or cutting construction wood.

You may vary your approach in mid stream if you find knots, rot or figure.

What it really boils down to is that you should learn as many reasons for turning a cant, opening a log or removing a board as you can so that you know, when the time comes, how to treat each individual log.

In my estimation, squaring a cant with 4 cuts will waste wood.  There are reasons to do so. Perhaps the log is small.   Perhaps the customer has requested it to save time (if you charge by the hour).  I resist the temptation to square with four cuts and prefer to test myself in getting the most from the log.

Rockn H

Randy, I think Tom gave some good advice as usual.  I just wanted to mention that some trees have alot more tension than others of the same species.  I sometimes notice the first slab bowing before I even finish the cut.

Randy

Thanks Again Tom!!!!!

Rockn H---I have noticed that. I cut a Oak today and every board bowed up on the end before I finshed the cut. It was a straight tree also. I cut another oak a few days back and it layed flat no matter which side I cut from. Randy

Rockn H

Randy, The other guys around here I'm sure can explain better, but I find if my first cut shows stress I can start taking cuts off of log on the side away from the direction that the first slab tried to bow.  It goes back to the heart being off center can make a board bow, if your board is already bowing use one bow to cancel out the other.  It is really one log at a time for me.  I can show you alot better than I can tell you.  Unfortunately I can't get a picture on here if I had to.

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