Outrigger Wave

[YellowHammer]

Occasionally, I have been the subject of periodic waves in my milled wood.  The pattern is very similar but not exactly like, a band resonance wave, with which I am very familiar and can easily adjust out.  Sometimes this particular wave pattern is very bad, it's unpredictable, and it always bothered me that I couldn't pin it down.  I've eliminated cam followers, bandwheel belts, loose blade guide arm, pretty much everything I could.  The good news is that my saw is generally well dialed in, and can cut as flat as a chalkboard, so when these waves would manifest themselves, they were really distinctive and would really puzzle me, as well as light me up.  My mill is an LT70, set under a barn roof, on clay ground.  Its flat, level and probably hasn't moved 2 feet in as many years.

So a couple days ago, the waves magically appeared after days of flat, no wave sawing. Here's a picture of what these waves looked like.  These are in the mid way point of the board, and I could make them occur any time I changed feed speeds, any time I engaged the debarker, etc.    





Since I was sawing walnut, I didn't want these to happen so I stopped and really started going over everything with a fine tooth comb.  I noticed that as the head was traveling, I could actually see the head wobble up and down a little, and tried to repeat the effect.  So I turned everything off, elevated the head as high as it would go, grabbed the outboard side of the head and started forcing it up and dawn with a vengeance, and noticed there was a good deal of frame flex.  This flex was allowing the head to rock up and down, and would take several seconds to dampen out. Then I noticed that the log loader outriggers that appeared to be were very tight to the ground were also flexing.  How could that be?  This made me take a serious think.

All the outriggers were firm enough into the ground that even when I kicked them, they felt solid.  There was no slack that I could see in any of them, as I check them routinely.  Then the lightbulb in my brain went off.  The rain we've been having routinely off and on had moistened the ground under the outriggers, and the outriggers were setting on slightly soft ground, even though the ground appeared hard.  I simply didn't have enough support.

I have the fine adjust outriggers, and proceeded to adjusted every single one down, only 1/2 turn, until I felt them fetch up.  Thats right, only 1/2 turn on each, equally.  I could feel them land on the solid base under where they had been.

So on the exact same log, the very next cut, success! Flat as a pancake.  No waves, anywhere, at any speed.  Amazing.  1/2 turn down on the outriggers went from unacceptable to sweet. 




 

The board (slab) on the right is the "before" picture.  Notice the waves on the face in some areas.  

The board on the left is the "after" picture.  Zero waves, same band, same log, same feed rate, same everything.  Very smooth cut.  This shows how critical even the small things can be to get flat wood.  I sawed the rest of the afternoon, zero issues.   

Ball game.

Maybe this experience will help others.       

[mike_belben]

Good info yh.  Thx for sharing.

[Bruno of NH]

I have the same issues when the frost comes out of the ground in the spring time.
Mud season

[jpassardi]

Nice diagnostic work. An easy long term solution may be to put timbers under the feet to displace the load and vibrations as the clay swells and shrinks back from moisture.

[customsawyer]

Good find.

[YellowHammer]

Big timbers should work in the mean time if it keeps raining every day but what do you mud season guys do?

Looks like a good place for for me to put a heavy concrete pad in this whole area.  Then add a few rubber mats to stand on.  The clay is generally so hard, I already use them at my console.  

What problems can I expect with the mill on concrete?  

[Percy]

Big timbers should work in the mean time if it keeps raining every day but what do you mud season guys do?

Looks like a good place for for me to put a heavy concrete pad in this whole area.  Then add a few rubber mats to stand on.  The clay is generally so hard, I already use them at my console.  

What problems can I expect with the mill on concrete?  

I've had my LT70 with a 6 foot extension mounted on a concrete slab with a steel frame for elevation. After carefully leveling, I bolted it down solid to the built up frame on advice from Woodmizer Salmon Arm. It is one of the best things I've done as all that constant adjusting is a thing of the past.Im hunting for pics.....https://forestryforum.com/board/index.php?topic=85674.msg1313016#msg1313016

[mike_belben]

Mass dampens vibration.  Its why high speed, high precision milling and turning centers are so darn heavy.  They wont produce a good finish if the whole chassis has random resonant frequency vibrations.  They used to be full of extra cast iron.. Now its a lot more epoxy granite. 

[moodnacreek]

With any sawmill not on or in concrete this sort of thing should be expected. That mill must be otherwise in very good shape to do such smooth work.

[csmall61]

YH, you can make out rigger pads just like the ones used on mobile cranes.

Take 1 x 6 hardwood, use a two layered cross pattern to make a 2ft square, and add rope handles and use 1 x 2 to make a box in the center for the foot to set in.

With these under every out rigger, it won't matter how muddy it gets.  I will try to get a picture of mine and post.

[YellowHammer]

Yep, the rig can cut as flat as a pancake.

If it happens more I'll make some of those crane outrigger pads. 

It's amazing how when the clay got moist it had some "give" and as I was rocking the saw head around by hand, it would flex like it was on rubber pads.  The legs were heavily loaded by the the weight of the mill, but the ground was elastic and was just bouncing around.

It makes me wonder how many others have had this problem and tried to readjust their mill until they got fed up when all they had to do was take a half crank down on every outrigger.  

In case anybody is wondering the cuts were made with a 1.5 inch .055 Turbo Silvertip.  It had been sharpened once but not set.  

I only set every other sharpen.  

[woodyone.john]

My standards for finish aren't as high as yours, but on some softer sites I've used 2 X8 or 10 spanning under the mill to land the 2 middle out riggers on them. For me this saved lots of time readjusting especially on heavier logs. Might work for you if a concrete slab is a way off.

[Sixacresand]

I set up at a customer's concrete pad today quickly realized the pad was not flat or all in one plane.  I don't have the fine adjust deals, but attempted to used wood shims make all the mill supports firm.  

I have seen that issue and assumed it just was an out of set blade a splinter stuck to a wheel belt.  

Thanks for sharing,  YH

[Bruno of NH]

I have crane type mats under some and 16"×16"×4" concrete masonary units under others.
I test the frost level with an iron bar daily during mud season.
I have hopes of pouring a pad this summer.

[KenMac]

I don't have a dog in this hunt, but I have noticed on a few YouTube videos this same appearing ripple effect. It seemed to occur at the start of the cut or, as you said, when feed speed slowed. Apparently, the guys just accepted it as normal and let it slide. Thanks for the interesting story YH.

[YellowHammer]

When my mill isn't cutting right, it just bothers me. :D

Not to mention it's embarrassing.

[Tom the Sawyer]

Robert,

I have had it both ways, on dirt and on concrete.  Concrete wins hands down, in my circumstances.  My mill is under cover, the roof of a lean-to on my barn, 10'x60', concrete full length. Slight slope to the concrete away from the barn.  I still offer mobile appointments so I may set the mill up under the lean-to once a week or so.  It is quick to set up and maintains its level (6 crank down 5000 lb Bulldog trailer swivel jacks).  

With the metal building wall and concrete surface, cleaning up the sawdust is easy, usually before setting up after a mobile appointment and, unlike dirt, I can get it clean.  I move it in and out with the skid steer or tractor and have painted the concrete under each wheel and the tongue jack so placement is repeatable.  Under the operators station I have a 4'x6' rubber stall mat that has been there about 10 years with no signs of deterioration, the mill and skid steer go over it every time I move the mill.  With the stall mat and accumulating sawdust, I have not had any foot issues from working on concrete.

[Crossroads]

I m another one who thought it was caused y a tooth or 2 out of set. Thank you for sharing what you found! One more reason for me to order the FAO's

[Gere Flewelling]

YH- This is impressive solution to the previously unexplained occurrence (for me anyway).  I am curious if you think it might affect a 4 post mill in a similar fashion.  I have a portable mill that sets on 6 jacks when set up.  I run into this issue occasionally, but mostly when sawing hemlock and pine.  I first noticed it when I tried a Timber Wolf band for the first time.  I just figured it was a characteristic of that brand of band.  Since I have noticed it from time to time with the Cook's bands I usually use.  I can't honestly say if the ground was soft under the mill when it happens.  I do set the jacks on hardwood boards in my yard when setting it up as in the spring the ground will allow the jacks to settle in to the dirt.   It is set up on turf and not compacted gravel.  Yours or anyone else's opinion on the would be appreciated.  Thanks, GF

[Tin Horse]

YH- This is impressive solution to the previously unexplained occurrence (for me anyway).  I am curious if you think it might affect a 4 post mill in a similar fashion.  I have a portable mill that sets on 6 jacks when set up.  I run into this issue occasionally, but mostly when sawing hemlock and pine.  I first noticed it when I tried a Timber Wolf band for the first time.  I just figured it was a characteristic of that brand of band.  Since I have noticed it from time to time with the Cook's bands I usually use.  I can't honestly say if the ground was soft under the mill when it happens.  I do set the jacks on hardwood boards in my yard when setting it up as in the spring the ground will allow the jacks to settle in to the dirt.   It is set up on turf and not compacted gravel.  Yours or anyone else's opinion on the would be appreciated.  Thanks, GF

On my 4 post Enercraft the frame work is very heavy. It is also supported on 6 outriggers. However when it sat on the ground with large planks under the feet it still moved. Log weight. I noticed when the head was up high and then lowered it would jitter downward. Took a while to figure out why. I always check the rails with a sight level ( transit). There would eventually be some twist or flex in the frame causing this. Problem gone now with mill under a roof and on pads to the bedrock. 8)

[JB Griffin]

Looks to me like you need to feed that pig. Those deep gullet blades have to be fed or they will do just that.
Also those silvertip blades are notorious for unequal and uneven set.
At my last job(running a Baker Dominator) i used nigh on 1000 silvertip blades from WM and at least two weld em up shops and nearly all of them had issues,
uneven set, no set on one side, set more on one side, bad tooth spacing at the weld(too much and too little), cupped(from WM that's pretty much guaranteed), wouldn't cut right outta the box( in particular i remember 8 boxes from WM that all had to be sharpened before they would cut), a visible step at the weld joint where the blade was misaligned, bad camber at weld(this was pretty much every blade), I won't buy them for my mill at all.

[Bruno of NH]

I have great results with the silver tips from a weld them up shop.
Cut great out of the box and perfect at the weld.
The blade life is great as well.

[YellowHammer]

I've also have had much higher cut quality with weld shop silver tips than DH bands.  Sawing quality is paramount to us, and I'm going to use the best band configuration I can.  This isn't about the band, it's about the sawmill.  

The proof is in the photos.  The board on the left was held to the exact same sawing variables as much as I could to the board on the right for this experiment.  The board on the right is wavy, the board on the left was very flat.  The only thing I adjusted was the firmness of the outriggers.  Nothing else.  

I electronically regulated the speed to the same speed.  The band was the very same from one cut to another, and the two boards were successive cuts.  The board on the left is a very clean cut, almost zero marks and the photo tells it all.  If I was having issues with feed rate or band geometry this board would not have been dead flat. 

These boards were fed at a relatively high feed rate, I.e my normal speed, and is the same speed shown on my YouTube videos.  

I'm not saying there aren't other factors that affect smooth cutting, speed, band, etc, but it was not a variable in this specific experiment due to electronic speed control and matching speeds for this experiment.  

These waves were caused by visible head shake and and was fixed by better supporting of the mill feet. 

[John S]

YH, thanks for posting this!

[JB Griffin]

My experience says that what you have done must be a fluke or some sort of issue that I have never seen before.  I have sawn millions of bdft with silvertip turbo 7's and have seen the EXACT washboarding only when feeding too slow. In my experience the turbo 7 profile should be fed at no less than approximately 60 fpm (1 ft per second) depending on width of cut to avoid washboarding. 

[Bruno of NH]

JB
I'm not a fan of your band of choice or their style of sales,
Not all weld them up shops are the same.

[DPatton]

YH,
   You have potentially shed some light on an issue I've been trying to figure out for some time. Our mills are nothing alike but I too on occasion have a similar blade vibration/oscillation issue that I've not yet been able to pin point. 

Unlike you almost all of my sawing is done on a mobile basis. So almost each and every day I saw is a new setup in a new location. I used to travel with 3 OSHA planks that I used for a base under my 3 pairs of outriggers. However In more recent times I have chosen to just carry and utilize a chunk of 5/4" x 12" x12" under each individual outrigger jack for ease of travel and transport. 

Some days I have no issues at all with my 4* Kasco blades from Cutting Edge. Usually I can cut perfect, smooth, lumber all day long. I use 4* Kasco's because of my horsepower limitations. My mill cuts real nice with Woodmizer turbo 7's in 18" and narrower cuts but I cut a lot of wide material and the Kasco 4*'s do well for me. However some days I get that wave. It drives me nuts and in the past I've gone as far as replacing blades, belts, bearings, adjusting belt tension, etc..... to try and make it go away. You may have just answered my problem regarding this issue. 

More to come!

[JB Griffin]

My blade of choice is 1.25x.045 7/35 Kasco for those who are interested.

I've tried turbo7, 7/47 among others that failed my expectations of what a blade should be. The deep gullet blades DEMAND high torque and my 33hp Kubota ain't got it to give, the BP Dominator had plenty, 50 3phase thoroughbreds.

I am a HUGE fan, you don't have to be, plenty of other blades out there.

I haven't found silvertips anywhere cheap enough to justify the inconsistencies. 

Nope, all weld em up shops aren't the same,  but they all get the exact same coil stock.

In my previous post I said that I saw the same things from the weld em up shops AND from WM.

All that to say I don't think it was just an outrigger problem.

[barbender]

I have never ran into inconsistency of any sort with Silvertips, or any WM band for that matter. I'm not saying it doesn't happen, but I've not seen it. My band usage is low enough that I would be more like "random samples"😁

[YellowHammer]

Moral of the story.  It's important to firmly and properly set the outriggers into the ground to fully support the mill to reduce its flex.  Solid ground, base, or pads.  That's what the outriggers are there for, and they make a difference, more so than I thought.  Start with the basics. 

As I mentioned earlier, I did the trouble shooting with the mill not running, and it's a process I'll repeat routinely if I start seeing waves where there were none. 

Grab the idle side wheel cover or whatever, and flex the head hard, up and down, up and down, by hand, and look for frame flexing.  There will be some, but not a lot. See if the outriggers are pumping into the ground. If they are, adjust them down or put a base on them until they are not.  Repeat the process of flexing the head up and down by hand until it is minimized.  If the flex has been reduced, you'll saw flatter boards, no matter what bands are used.  

I think this is so easy, I've overlooked it's importance.  

There are many, many other causes of wavy sawing, this certainly isn't the only one to watch out for. However, making sure my outriggers are solid and secure has been added to my list.  I had never really considered it a potential problem because my mill is stationary, but things happen.
  
I am very familiar with wavy cuts caused by blade resonance issues that look very similar to this, caused by a poor match of band to the wood, slow sawing speed, sawdust under the band wheel belt, etc.  We've all had many discussions on the subject. However, this is not that.  

As far as bands, on this mill alone (my third) I've used DH 055-10's, DH 045-9's, DH 055-9s, DH 055-7's, DH 055 Turbos, DH 055-4's, Kasco 055 7's, Kasco 055 7/40 (basically the WM Turbo), WM carbides, the DH 055 747's and Silvertip 055 Turbos.  I routinely saw maybe two dozen different hardwood species, some very hard, (pecan) and some very soft (basswood). This mill does like pretty much all of the band geometries, it's pretty forgiving, although the carbide and the Turbo style, both in Kasco and WM consistently perform best, with faster and smoother cuts.   I get very good performance and have selected the 055 x 1.5" Turbo Silvertips as my standard band now.  

[ladylake]

YH,
  You have potentially shed some light on an issue I've been trying to figure out for some time. Our mills are nothing alike but I too on occasion have a similar blade vibration/oscillation issue that I've not yet been able to pin point.

Unlike you almost all of my sawing is done on a mobile basis. So almost each and every day I saw is a new setup in a new location. I used to travel with 3 OSHA planks that I used for a base under my 3 pairs of outriggers. However In more recent times I have chosen to just carry and utilize a chunk of 5/4" x 12" x12" under each individual outrigger jack for ease of travel and transport.

Some days I have no issues at all with my 4* Kasco blades from Cutting Edge. Usually I can cut perfect, smooth, lumber all day long. I use 4* Kasco's because of my horsepower limitations. My mill cuts real nice with Woodmizer turbo 7's in 18" and narrower cuts but I cut a lot of wide material and the Kasco 4*'s do well for me. However some days I get that wave. It drives me nuts and in the past I've gone as far as replacing blades, belts, bearings, adjusting belt tension, etc..... to try and make it go away. You may have just answered my problem regarding this issue.

More to come!

Do you have the down pressure set at least 1/4".   Steve

[Bruno of NH]

I pay $16.00 delivered to my mill for WM 1.25 t7's 
I can buy 5 to 50 any quantity and pay the same.
Not 15 blades at once 
Weld em up boys 

[JB Griffin]

I've said my piece, my experience tells me otherwise.
Having sawn millions of bdft with 5 different mills (1 keenerbuilt, 1 WM, 3 Bakers) I have never seen that even when the mill was loose from the ground/concrete even so much that outriggers came off the ground when the log hit the backstops when loading.

[Bruno of NH]

@JB Griffin 
O'Doyle Rules  :D :D

[Gere Flewelling]

YH- The timing of this post is great.  I was at a customers site today sawing large white pine logs and noticed the diagonal waves starting to show up on the cuts.  Went and checked the jacks and found they were not applying enough ground pressure in the center and one on the further end.  I was set up in a sandy gravel driveway that seemed hard enough at first, but rolling 16'x 30" dia. logs slams down pretty hard and apparently hammered out the dirt under the jacks.  When I adjusted the loose jacks, the lines went away.  Hit a couple of nails today,  :embarassed: wish I could find an answer to that issue like for the diagonal waves.  Metal detector didn't catch them.  Thanks for the help.  GF

[YellowHammer]

That is great news.  I'm glad it helped.  8) 8)

[DPatton]

YH,
  You have potentially shed some light on an issue I've been trying to figure out for some time. Our mills are nothing alike but I too on occasion have a similar blade vibration/oscillation issue that I've not yet been able to pin point.

Unlike you almost all of my sawing is done on a mobile basis. So almost each and every day I saw is a new setup in a new location. I used to travel with 3 OSHA planks that I used for a base under my 3 pairs of outriggers. However In more recent times I have chosen to just carry and utilize a chunk of 5/4" x 12" x12" under each individual outrigger jack for ease of travel and transport.

Some days I have no issues at all with my 4* Kasco blades from Cutting Edge. Usually I can cut perfect, smooth, lumber all day long. I use 4* Kasco's because of my horsepower limitations. My mill cuts real nice with Woodmizer turbo 7's in 18" and narrower cuts but I cut a lot of wide material and the Kasco 4*'s do well for me. However some days I get that wave. It drives me nuts and in the past I've gone as far as replacing blades, belts, bearings, adjusting belt tension, etc..... to try and make it go away. You may have just answered my problem regarding this issue.

More to come!

Do you have the down pressure set at least 1/4".   Steve

Yes, I have been running the 1/4" down pressure for several years after reading about it here on the FF. 
However this topic got me to thinking about times that I have seen wave occur at what I can only explain as as certain point of saw head travel down the deck. It wouldn't be reoccurring or repeat itself anywhere else in the cut like it does if it's the blade, or sawdust buildup on or under the belts. I check for buildup or debris on the track and chain rail as well but have never really pinpointed what may have been the cause. Like I said every day I saw is a different setup. Some days it's frozen, some days thawing, some muddy, and some dry and solid under the mill. Sometimes The client bumps the mill around while loading a log onto the lifting arms with support equipment. All of these can change how firmly the jacks are planted and how straight the mill bed stays at any given time.
 I'm happy to say that I ran all day yesterday sawing 4000 bf of walnut slabs without any waves.

[TroyC]

Glad to see this post. Last time I set my EZ40 up I had several washboards like the photo. I'll check the pressure on the jacks next time. Thanks!

[Stephen1]

Interesting for sure and something I will watch for. I get it all the time, on and off of course. I have chalked it up to not sawing fast enough, so I would speed up if I could on the next pass, you mention you slowed down and it appeared. I am going to start checking my outriggers more, in fact I think I will invest in 4 FAOR. I also find I have trouble putting blocking under my outriggers. unless I put the wheels up on the blocking also. The outriggers are too tall and so match the bunks if not a little higher.  I set my mill up every day. I am at different sites, in my yard I set up every day and put my mill away every night. I do not leave my mill out at night as my shop is in a industrial setting and machinery does dissapear. 
I have switched to .55 silvertips 7/39. I just started using them last week. I like them so far, I can now hear the motor work consistently,the govenor kicking in.  1st time really since I bought the mill. I can push the mill now. The cuts were flat. All the sawing I did this week was 26" plus logs, soft and hardwood.  I do have a question on the sawdust left though. Should I widen the set when I sharpen? What set are you using?
This is the 1st log I used the new blades on at a customers, good test, dead and semi dried out big ugly ash. A little trimming and pushing to get the mill through it. 

 

[Satamax]

Yellowhammer. I don't know if this can be of any use. 

But when i set up my saw. A friend of mine dug the ground, into which we set 12 barrels, at approximately the same height. I did check with my laser. He backfilled around, and we filled up those with lean concrete. You can vaguely make the barrels out in the following photos. 

They're about right under the freezing line over here. Which is about a yard down. 



 

 

[YellowHammer]

Satamax, thanks, I'll look into, it.

Stephen1, I don't do much about the set. I just set them to .023, you can see how much sawdust I have on my boards.  They are pretty clean and dry.

[Stephen1]

I have started using the new to me wider thicker blades. 1.5" .55 silvertips 7/39 turbo's.
I also read this post at the same time I started the new blades. 
Here are my observations about this issue.
I called it corduroy, from sawing to slow or what we have been told by a lot of people. 
YH brings up and observes  and names it. " Outrigger Wave" or OW
I set up this week at my shop on uneven pavement as I always do. The 4 inner outriggers have to be shimmed as the pavement is not level under the mill. I do not have the FAOR on the inner 4
I used to leave them loose, give them a kick wiggle loose. I would get the corduroy on and off using the 1.25" blades. 
I observed corduroy this week using the new stronger blades very consistantly. I actually sawed some wedges from the log I was sawing and hammered them under the 4 outriggers. The corduroy or OW dissapeared.
I think the stronger blades, result's in us pushing the mill's to motor's limits. The bigger motors give us more torque? You then need to do what YH says and set your mill up to utilize the design of the mill. make sure the outriggers are solid.  
I will have to buy the FAOR for my mill, especially if I continue to use the stronger blades.  

[John S]

The FAOS make quite a difference in set up, especially for mobile jobs.  Shims are a thing of the past.  I will be making wide pads to place below each one for more stability. This is a welcome thread.

[YellowHammer]

I called it corduroy, from sawing too slow or what we have been told by a lot of people.
YH brings up and observes  and names it. " Outrigger Wave" or OW

I observed corduroy this week using the new stronger blades very consistantly. I actually sawed some wedges from the log I was sawing and hammered them under the 4 outriggers.

The corduroy or OW dissapeared.

That is OUTSTANDING! 8) 8)