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Woodmizer Alignment issues???

Started by nstringer04, February 04, 2015, 06:44:04 PM

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nstringer04

I have been sawing 8x and 12x mat timbers for awhile now and have noticed that my timbers are tapered. Sometimes it's as bad as 1". What are the common causes for this? The logs I cut are 16', 18', and 20' in length. All hardwood. On the entry end of the timber it's usually a little smaller than what it should be and on the exit end it is larger than its supposed to be.
A ship is safe in harbor, but that's not what ships are for.

slider

I would do a full alignment first then go from there.Tension can cause problems but not on the first entry in to the cut.al
al glenn

POSTON WIDEHEAD

I agree Slider.....a little out of alignment can be a lot at 20 foot.  :)
The older I get I wish my body could Re-Gen.

uler3161

An inch? Wow.

I think I'd look at a few things before doing an alignment...

1. Check how well you're supporting the ends of the logs, especially those 20 footers.

2. Watch as you cut to see if the log is bowing. This may be more noticeable when you have a flat edge down on the bed rails since at that point, the log should be sitting on all the rails. I'm not as well versed on how hardwood will act, but on softwood sometimes I'll get part way into my first cut and the slab will start moving all over the place. At that point I know to expect some issues with bowing.

3. Make sure you don't have anything between the log and any of the rails. It's usually bark or if you forget to lower a toe board.

4. Measure from your blade down to each rail including the swinging ones. Make sure those are all consistent. If not, it's time for alignment. You didn't say what WM you have, but if you have an LT40 or similar, I'd also suggest opening your blade guide all the way and measuring both on the drive side and the idle side to make sure there's not a serious difference in height. As I recall, there should be a small difference to account for the cantilever. If you have a smaller WM that might not be the case.

Sometimes I'll have a dull blade and/or some strange stress in the log and if I push the mill too hard my blade will ride up. Not as noticeable until I get through my cut and see the blade drop. I think I've had it do that close to 1/2 an inch, but I've never seen a whole inch.



1989 LT40HD, WoodMaster 718

Dan

nstringer04

1" is a slight exaggeration. It's usually between 1/2-3/4 at its worst. 1/2 is usually the norm. However I did have one today that hit the 7/8 mark. I do see the blade drop even with a new one slowed down. Gonna do a full alignment in a few days. Maybe that will fix it.
A ship is safe in harbor, but that's not what ships are for.

uler3161

An alignment is a good idea, but I think you should check the alignment by measuring things before taking anything apart. Though I think blade drop is going to be an alignment issue, but I don't think it's your only issue.

I'm actually a bit skeptical about the alignment being the main problem because if I'm visualizing it correctly, either that blade is dropping a huge amount when you come out of your cut, or the bed rail closest to the end of your cut is WAY low (along with all the other rails, though not as much).

If the blade was dropping 7/8 it'd be pretty obvious. The rail being too low might not be as obvious, but those things don't get out of alignment that far unless you take some of the adjustment bolts out. I think with bed rails being out of adjustment, you'd also be seeing it consistently off. As in, all 20 footers would be 7/8 off and I get the feeling it's not that consistent.
1989 LT40HD, WoodMaster 718

Dan

Peter Drouin

Just because you have a new blade don't make it a sharp one. To me It sounds like a dull blade and cutting to slow. Do you have a alignment tool to see if the blade is level to the bed? [Front to back]
A&P saw Mill LLC.
45' of Wood Mizer, cutting since 1987.
License NH softwood grader.

MartyParsons

Hello,
Here are some things to think about.
If every can't is the same then I would say it would be an alignment issue. 
The front leg and rear leg must be supported on the long cuts , over 10'.
Alignment should be from blade to bed. Best way is to check every bed rail and document the measurement on the bed rail with a marker. Don't adjust until you check each bed rail. Most times they will all be the same. Movable bed rails can get grease and sawdust between the nut and the mount. Check before you make the adjustment.
I like to use 18" but the height you use is not important. Long steel rule 24" works well. Tape measures are not as accurate.
Hope this helps.
Marty
"A pessimist sees difficulty in every opportunity; an optimist sees opportunity in every difficulty." -Winston Churchill

Percy

Quote from: MartyParsons on February 04, 2015, 09:40:11 PM

The front leg and rear leg must be supported on the long cuts , over 10'.

Marty
When I had the same problem, this was the culprit. In my case, a structural wooden beam on my floor had given out and when the head was at that end, the frame, being unsupported with the weight of the whole head on it would flex about 1/4 inch. Flip the beam and make another cut and you have 1/2 inch total undersized deviation. It was an easy fix...:D
GOLDEN RULE : The guy with the gold, makes the rules.

terrifictimbersllc

Assuming you mean timbers, 8x and 12x being inches.  These will be stiff and not sag over very long length like 8/4 or 12/4 will.

Main rail of mill must be straight (a setup issue, front or back supports as Marty said most critical) to cut uniform thickness timbers.  Put the head at the front, and sight the rail from the back end. With practice it's easy to see whether its straight, and with shims or fine adjust outriggers to get it so that timbers are within a sixteenth of thickness throughout.  Put the head at the front, the weight is setting on the three front outriggers, and you can see the rail flex when jacking up or removing support of the back outrigger.  Unless you're on concrete or other very hard surface,  this straight setup will change during a milling day, it requires attention.

With practice, one can also sight along the cut timber especially at a square edge and see whether the cut is straight or curved.  It would help to know which you are experiencing.
DJ Hoover, Terrific Timbers LLC,  Mystic CT Woodmizer Million Board Foot Club member. 2019 LT70 Super Wide 55 Yanmar,  LogRite fetching arch, WM BMS250 sharpener/BMT250 setter.  2001 F350 7.3L PSD 6 spd manual ZF 4x4 Crew Cab Long Bed

nstringer04

Checked the legs out. A couple were not stable. Fixed that problem and now it cuts better. Still have about a half inch taper on most if not all timbers. I'm waiting on some 7 degree turbo blades and someone that is supposed to come help me do an alignment soon. Thanks for the help on here guys. I don't have anyone local right now. Perkinston Woodmizer was my closest parts and service.
A ship is safe in harbor, but that's not what ships are for.

mikeb1079

i'll bet your band is slightly out of parallel to your bunks causing your bands to raise ever so slightly in the cut
that's why you must play di drum...to blow the big guys mind!
homebuilt 16hp mill
99 wm superhydraulic w/42hp kubota

reubenT

Blade maintenance is the no. 1 issue with the band mill.      Get it sharp and set right.   The alignment checked.  And then watch the cant bow up or down as you take a board off. The thicker the board the worse it is.  I've had em a good inch off when the cant end was hanging out too far beyond the last support.     Most will bow up in the middle and down on the ends with board rising on the entry end,  making a board with thick center and thin end.   a few may bow the opposite way.  May be sitting strait when entering and be way off at the other end.  A low tech not too accurate solution is to watch the thickness and roll the up/down pulley by hand to adjust for the bow.   More accurate to make sure the cant is well supported both ends and lock the middle down with the dog.   But on the occasional reverse stressed log that will have no effect.  It's those reverse stress logs that cause a problem on a circle mill, slab or board digging into back side of blade. I've heard of them throwing a slab violently.  When I get it put together I'll put a guard on mine to block it from throwing things at me.

prittgers

I have experienced this problem.  In my case, the torsion tube was stressed due to the frost going out from under the end where I parked the head.  It happened daily around late morning.  Installing the Fine Adjust Outriggers on front and back made the problem easily correctable.  You can phone me for particulars.  907.360.2497.  Parker
Parker Rittgers
Professional Sawyer, Retired, well, not really !
WoodMizer Alaska | 907.360.2497 cell 336.5143 office BevelSider.com ? Everything BevelSider
907.336.5143
prittgers@aksamill.com

learner

Other than the basic alignments be sure to check the wear pad gap.  If it gets too loose your blade can flex and move up and down.  I keep mine at .010 and check it every 3 blades.  There is NO truly vibration proof piece of equipment and even normal wear and tear can change some of the finer adjustments.  It only takes about five minutes if you have to readjust it and it saves in the long run on bad cuts.  Also, if you enter the cut slowly and let the blade settle to its comfortable level you shouldn't loose more than a couple of inches of usable wood on the opening cut.  Also check your cant when you clamp it and if the center is up off the bunks, just push the down lever on the hydraulics and the clamp should pull the center of the cant down against the bunks.  If your using the LT40, drop your side supports a hair too, to make sure the inner side of your cant is down against the bunks.  Be prepared for the stress in any log to cause your last board to be off on the entry and exit cuts due to the cant extending past the last bunks on each end.  This is why we buck all our logs to 8'6", 10'6" etc..  It allows us to cut 3" off each end if the cut is off or the ends have cracks.  Best of luck with everything.
WoodMizer LT40 Super Hydraulic, MF-300 FEL, Nissan Enduro 60 forklift, 2 Monkey Wards Power Kraft Radial arm saws, Rockwell series 22-200 planer, Prentiss 210 loader

learner

Sorry, I almost forgot!  Watch your feed speed too because those knots just LOVE to cause your blade to wave up and down throughout the log.
WoodMizer LT40 Super Hydraulic, MF-300 FEL, Nissan Enduro 60 forklift, 2 Monkey Wards Power Kraft Radial arm saws, Rockwell series 22-200 planer, Prentiss 210 loader

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