Last Board Uneven - woodmizer

[Woodslabs]

Hi All,

I have a LT15 wide and have noticed a small issue.  So i will mill a log, once i am close to the clamps i will flip it.  Once i get to the very last board it sometimes does not come out even.  By this i mean that at one end it is 2 inches and the other it is 1 and 7/8 or worse.  I don't think its the rails as the log rests on the supports which are connected to the rails.  I originally thought that there may be a small wave when the blade enters the log but it looks pretty smooth.  Its almost like i need to shim one side a 1/8th after turning the log to get a perfect cut.  Anyone experience this and have any advice?  Since the narrower end is on the far end of the cut i would need to shim the start of the cut 1/8th to get an even cut on the last board?  Also how much do you guys calculate in terms of loss of material due to blade per cut?

[Woodslabs]

I found a similar thread.  I will mill tomorrow and see if its tension in the wood moving it up

[Brucer]

Just what I was about to suggest.

When you flip it, check to see if the cant is sitting flat on all the supports.

[ladylake]

 Plus try and get far end of the cant on a bunk or overhanging just a couple of inches.   Steve

[Sixacresand]

I can't imagine mill alignment causing this.  I'm guessing tension in cant causing it to rise or dip, or a diving or rising dull blade.

[DansSawmill]

if its tension, try to flip the log every few boards, especially as you get close to center

[Woodslabs]

Ok so i noticed something today.  After the cut when running the saw back at the far end the blade is 1/8 above the wood and at the cut start end its flush.  How is that possible.  Its like the blade is pulled down or the wood is pulled up....

[drobertson]

this sounds like a typical stress reaction to me,  not there but if the previous boards are fine relatively speaking, then its' stress, other wise all the boards would show signs of diving or waving or whatever, 

[Woodslabs]

is there any way to minimize this without rotating the log?

[Woodslabs]

One thing i forgot to mention.  So as soon as i turn the log so that it sits flat, i sjin the other side i have a 1/16 or 1/8 size difference.  Can stress happen that early in the cuts?

I usually will skin and mill a log until the blade will hit the breaks on the next pass, i flip it at that point.

[gfadvm]

I'll be following this thread trying to learn something. I have had exactly the same experience with my LT15. It seems to only occur when I cut maximum width (24") oak or hickory. That last board will be flat on one side with a taper the last 3-4" on the other.

[Percy]

I get/got similar issues on my old LT40 and my 12 yearold LT70....havent figured it yet. The best I can come up with is that last cut is only supported by the one bottom board and while  it is nearly finished being cut, very little wood is holding the two boards together and some "unbeknownst to me" force is acting upon them causing the slight deviation. An 8th is nothing to get wigged about but it would be nice to figure it out....

[Jim_Rogers]

Ok so i noticed something today.  After the cut when running the saw back at the far end the blade is 1/8 above the wood and at the cut start end its flush.  How is that possible.  Its like the blade is pulled down or the wood is pulled up....

Normally when the blade dives down into the log like what you are describing it is because the blade is dull on one side.
A truly sharp blade should exit the cut level with the top of the cant.

If it drops down, it is dull. If it rise up it is dull on the other side.
With wide cuts it is easy to get a dull blade quickly.

Jim Rogers

[timberjackrob]

sounds like normal stress in the log to me as mention before bout all you can do is turn the cant more often.

[Woodslabs]

Ok so i used the blade alignment tool and it is off about 1/8 pointing down.  I tried finding how to adjust the pitch in the awful manual but cant find any info.  I need to pitch the blade up a little.  do i adjust something close to the tensioner leaver or is it by the rollers?

[Magicman]

No offense intended, but not understanding the adjustments as outlined in the manual does not make it an "awful manual".   All of the adjustments are outlined in the sequence that they should be done.

The ¼" downward blade deflection should be done first.

Then move to the blade guide vertical tilt adjustment.  Each blade guide has adjustments necessary to properly adjust the blade guides vertical tilt.

Blade guide spacing is next followed by the horizontal tilt adjustment.

[Woodslabs]

No offense intended, but not understanding the adjustments as outlined in the manual does not make it an "awful manual".   All of the adjustments are outlined in the sequence that they should be done.

The ¼" downward blade deflection should be done first.

Then move to the blade guide vertical tilt adjustment.  Each blade guide has adjustments necessary to properly adjust the blade guides vertical tilt.

Blade guide spacing is next followed by the horizontal tilt adjustment.

I may be looking at the wrong manual.  I cant remember if i got 1 or 2.  I have the Equipment manual and it has a very small section about maintenance only outlining when it needs to be done but not how.

[Magicman]

Maybe someone will weigh in that has an LT15 and can point you in the right direction.  Questions are good and you will get the help necessary to get squared away.   

Edit:  @MartyParsons

[Woodslabs]

I found an online manual.  So it looks like i can adjust the angle by adjusting the angle of the rollers.  So i need to take the nuts off and adjust the bolts using an alan key.  I would assume i loosen the bottom and tighten the top?

Sorry for the annoying questions.

[Magicman]

The only annoying or dumb questions are unasked questions.    Also, if you do not have the adjustments in your manual, it was awful.   :D

Yes to your adjustment question, but a little goes a long way so make slight adjustment and check.  You will get the feel of it. 

[Woodslabs]

The only annoying or dumb questions are unasked questions.    Also, if you do not have the adjustments in your manual, it was awful.   :D

Yes to your adjustment question, but a little goes a long way so make slight adjustment and check.  You will get the feel of it.

Awesome.  I found the adjustment steps online and printed them out.  Will let you guys know how i make out tomorrow and if it fixes my "dog board" problem

One more question:  I see you should rotate the  blade wheel belts every 50 hours.  By rotate do they mean flip inside out and reinstall?

[timberjackrob]

I found an online manual.  So it looks like i can adjust the angle by adjusting the angle of the rollers.  So i need to take the nuts off and adjust the bolts using an alan key.  I would assume i loosen the bottom and tighten the top?

Sorry for the annoying questions.

yes that should do the trick just looked it up in my manual it is a lt 28 but I think they had same saw head as 15

[MartyParsons]

Hello,
   Measure from the blade to the bed rail. Take a marker and document this measurement on that rail and every other rail. I do it at 18" but the number is not important. They should all be the same. There should be 1/16" higher on the idle side. You should use a STEEL ruler not a tape measure. Make sure the ruler is not leaned forward or back. It should be the same place on each bed rail. If this measurement is off then we need to adjust. Follow the manual. Remove the deflection check the blade to bed rail again. Check blade guide arm adjustment then raise the saw head 1/4" above the bed rail. 18 1/4 on the drive side and 18 5/16 on the idle side. Install the blade guide rollers. ( New B-57 belts should be used) adjust the rollers so the blade measurement is 18" on the drive side and 18 1/16 on the idle side. Then check the blade tilt with the blade tool. Adjust so that the measurement is the same front to back. Recheck your 18" and 18 1/6" from the blade to the bed. If this measurement changed remove or install more deflection it needs to be 18" and 18 1/16".   Last thing is to check the pointer on the scale adjust after measuring from the bottom set tooth on the drive side to the bed rail.

Sorry this is a crash course. Ask more questions and I will clarify if needed.

Hope this helps. 

Marty

[beenthere]

Ok so i used the blade alignment tool and it is off about 1/8 pointing down.  I tried finding how to adjust the pitch in the awful manual but cant find any info. I need to pitch the blade up a little.  do i adjust something close to the tensioner leaver or is it by the rollers?

Not sure what you mean by "pitch the blade up a little", but think MartyParsons says to use the blade tilt tool so there is no pitch up or down.  Just flat and same.  Maybe I've misunderstood what you were thinking you needed to do to solve a problem.

[drobertson]

Sounds like you are on the right track now, this will be a very valuable learning experience for you.  Pretty sure most folks have dealt with alignments at one time or other, and done some tail chasing ;D  it really is the only way to truly understand your mill.  There will be many more little things that come up along the way in the milling journey.  I say take notes, keep a log book, and above all try to remember some these things you discover and what others have shared. Lots of good help here,

[pineywoods]

I see this happen on my lt40 occasionally, but it's usually because the sawmill grimlins sneak out and raise the toe roller just a smidgin  ;D Seriously, here's something that will bite you. most of us start sawing from the small end. If you cut a log that had a big swelled root flare, boards cut from that flare will most likely bend, no matter what you do. Follow Magicman's advice and flip the cant frequently to minimize the bending...

[bkaimwood]

No doubt with what you've checked and come up with so far indicates your mill needs an alignment regardless, but likely not the solution. No skin off your back, should be done anyway. It happens to me more often than I'd like to admit...I get in production mode, pay less attention to stress, get lazy and don't want to flip the cant...but pay for it on the last board, at the very least... We all need to remember, as much we think we are in charge, we are not...the log or cant is...it tells us what to do next, we just have to follow, and stick to, and respect IT'S plan...

[Magicman]

Exactly.  Reading the log and opening the correct face, then watching and reacting accordingly.  :P

[gfadvm]

Hello,
   Measure from the blade to the bed rail. Take a marker and document this measurement on that rail and every other rail. I do it at 18" but the number is not important. They should all be the same. There should be 1/16" higher on the idle side. You should use a STEEL ruler not a tape measure. Make sure the ruler is not leaned forward or back. It should be the same place on each bed rail. If this measurement is off then we need to adjust. Follow the manual. Remove the deflection check the blade to bed rail again. Check blade guide arm adjustment then raise the saw head 1/4" above the bed rail. 18 1/4 on the drive side and 18 5/16 on the idle side. Install the blade guide rollers. ( New B-57 belts should be used) adjust the rollers so the blade measurement is 18" on the drive side and 18 1/16 on the idle side. Then check the blade tilt with the blade tool. Adjust so that the measurement is the same front to back. Recheck your 18" and 18 1/6" from the blade to the bed. If this measurement changed remove or install more deflection it needs to be 18" and 18 1/16".   Last thing is to check the pointer on the scale adjust after measuring from the bottom set tooth on the drive side to the bed rail.

Sorry this is a crash course. Ask more questions and I will clarify if needed.

Hope this helps. 

Marty

Marty, I learn something every time you post. Thanks.

[Jim_Rogers]

When flipping a large piece with some stress in it, I try as best I can to take even amounts off of each side.
And I try and end up with the bottom piece, the one that may not be 100% correct thickness or shape to have the heart/pith of the tree in it. Usually this piece can/could be one of the lowest quality pieces because of the pith. If it is low quality and it isn't the correct shape or size then it doesn't really matter that much.

Jim Rogers

[bkaimwood]

The most frustrating part of this whole "cant stress" dance to me, it that every flip and counter measure taken, decreases board with by at least 1" in most cases... Therefore decreasing lumber value...in some situations, firewood is of more value than the thinner boards I'm forced to cut as the cant narrows... But crooked boards ain't worth nothin'...

[drobertson]

The real issue here as I read it is even boards, even thicknesses.  Crook will come and go and while some of the issues is easy(relatively)speaking, to handle, other times not so.  Some folks have a general knowledge of what a log will produce, and they hope it will, but not all logs give out the desired return for a given project, and again the logs are not available when things go south. Not meaning south is a bad thing, just saying I've sawn for many with limited logs and a cut list that barely covers the cut list.   Knowing the end use is of the utmost importance in determining the pattern chosen.  It just takes time to figure how logs work and the product that comes from them. And this at best is the best guess, wood is wood, it moves around at times.

[Magicman]

The most frustrating part of this whole "cant stress" dance to me, it that every flip and counter measure taken, decreases board with by at least 1" in most cases...

No.  You flip the cant 180° which does not reduce the width.  That is unless I am misreading your statement. ??

[5quarter]

Have you checked to see if your second to last board is thick at the end? if it's stress, both boards will be uneven. if its an alignment issue, then only the dog board will be affected. Also, does your clamp pull down at all on the cant? if it does, it may be pulling the cant down in the middle slightly which will lift up the end of the cant and cause the dog board to be thin at the end of the cut. Good luck.

[bkaimwood]

Hey MM...not necessary a misread...I saw by far more ugly logs than saw logs...not by choice...taking this into account, I can saw textbook, pith centered, proper opening face on crooked logs, and still end up with this situation... I'm sawing, see a board end or middle start to react, react myself accordingly, and flip 180, and continue sawing...other times, I will see the board on the entry side crook right or left, indicating that a 90 degree flip is in order to releive tension on that side of the cant, and correct the crook or sweep that will be in the boards if you continue without reacting... This is where you the board width is decreased...help me if there's something else I could be doing in this situation...

[Magicman]

If you saw down from either the hump or horn faces, you should not encounter crook.  I said "should" because the log is always boss.   ;D

[bkaimwood]

I always do MM...but sawing sub-par logs does unfortunately create this situation for me...happens on maybe half of my sub par logs, which tend to be more often hardwood... Less often in softwoods... Was hoping u had a MM magical cure I had overlooked, but as discussed, the log is boss...

[Magicman]

If logs are like camels, I like the "Dromedary" logs.

Yup, twisting logs have two humps so maybe they are "Bactrian" logs.    They end up being more of a "sacrifice & salvage" job than a sawing job.  I always point that out to the customer beforehand and let him know not to expect much out of that log.   I remind him that I can not make chicken pie out of chicken mess.   Make light of it, saw it and do the best that you can, and move on to a better log.  ;D

[Woodslabs]

Looks like the blade deflection adjustment fixed the issue

[Brucer]

 And after all, that's what this topic was all about  .