Woodmizer vibration in band and the mill is buzzing, help! -- Update

[RPowers]

There is something off-kilter in my mill and I can't isolate it. I parked it at my house after the last away job, used it to cut a mbf or so, then tarped it and haven't used it for about a month due to other projects and bad weather. I uncovered it and started checking everything a couple days ago in preparation for an upcoming job, and now it is making a loud buzz/hum when the blade is running. It was somewhat of an oscillating noise, and I could see the band flutter with every peak, so I suspected sawdust buildup or guide roller misalignment. So I cleaned the belts, put on a new band, and it still was doing it.

Before this the noisiest thing when the mill was cutting was the engine at high rpms, and that "shick-shick" sound of the guide rollers spinning, now this aweful buzz is the loudest thing. It sounds very similar to those big tree service chippers, and when I throw the clutch lever to shut it off you can hear that buzz "spool down" for lack of a better term. It is in the area of the main drive wheel. I've checked all bearings for play and none seem hot or loose. I did a routine alignment and got everything spot-on to within 1/32". Now the band runs straight as a string except when the outer guide roller is all the way in, then it flutters nonstop. Do I need to put more down-pressure at that position to fix this, or less down-pressure? It is frustrating to throw the guide arm half-to-all the way out and see the band so straight it looks still, and then pull it in and the thing is oscillating.  If the drive belt tension is too high what will that cause? And that darned buzz is still there and I can't find it. It actually vibrated a bolt out yesterday, I keep waiting for something to come apart so I can find the source... but I'd rather locate and adjust it before that. The oscillation is bad enough to leave tooth waves on my boards, not wavy cuts, just 1/2" apart chatters about 1/32" deep. The mill was cutting smooth a few weeks ago, and has not been moved at all.

I know with the tens of thousands of combined hours you all have on Woodmizers someone has seen something like this before. Help!  :-\

I'm posting this in the WM forum as well for anyone who goes there more often.

[JustinW_NZ]

Main drive bearing if going to do all sorts of very odd things like you say.

Its not old?

Cheers
Justin

[backwoods sawyer]

 Hope it is not something serious!
However it sounds like a flat spot on a guide roller, ice and crud could have stopped the bearing while milling on your last job and now that it has warmed up it can now spin. A flat spot on the guide roller will buzzzzz, you should be able to see and feel a flat spot, 

[Peter Drouin]

Check the measurement of the guide arm to the bed should be the same all the way out or in. then when you have the mill runing put your hand on the blade covers and the cover on the side . theres a lot vibration the covers will buzz some. your hand will stop it.Maybe this will help?

[drobertson]

Not sure about the buzzing sound, but the blade guide roller is an easy one, it sounds like your adjustment bolt on one of the v-guide bearings needs tightened back.  Mine takes a 15/16" and a 1-1/8, then you will need to ensure the height is right to the bed while moving it in and out.   david

[Chuck White]

A loose nut on one of the blade covers will make a loud vibration noise!

Might check the center throat bolt!

[Magicman]

Check to be sure that there is not a piece of bark tightly wedged into a groove on one of the guide rollers.

[Jim_Rogers]

Check for sawdust build up under the blade v-belts for vibration issues.

Jim Rogers

[isawlogs]

 I have a stethoscpe for mechanic work, it has a rod at the end where a DR would have the cup. Get one or use a hardwoos dowel and poke around with it till you find the loudest spot, that will be where the issue is.

  Take the blade off your mill and first eleminate the idler wheel bearing, and also you will eleminate the sawdust behind the drive wheel v-belts. Now once the blade is off and you still have the noise, poke around with dowel to your good ear  ;)  and locate where the noise is coming from .

  Vome back and let us know what is the issue .  :P

[Ga Mtn Man]

The one time I've heard a noise similar to what you're describing was when re-installing the blade cover, I missed one of the "shoulders" that the cover rests on and the blade was try cut it's way through it  .

Have you tried a different blade?

Raise the roller guides above the blade and see if the noise goes away.

[RPowers]

Thanks so much for all the ideas! I have alot of things to check now. I have already pushed on everything that could be loose while the mill was running to see if a cover or something was the source, but it wasn't any of those. I felt around with the blade running and the vibration feels the strongest around the inboard guide roller area. I'll check that for flat spots and re-check everything for bark or dust stuck somewhere. I think I've checked everything at least once already, but I can miss things the more frustrated I get. I'll keep everyone posted on any changes, if just so that others might be able to diagnose the same problem in the future.
Thanks,
RP

[Peter Drouin]

I did have a new b57 belt have a lump in it would not run right. I put the old one back on and it worked fine.

[Brucer]

Try Marcel's suggestion and run it without the blade. If the problem persists, it will have something to do with the drive or the drive side bandwheel. If it doesn't, it could be one of the blade guides or the outboard bandwheel. Or it could be something under one of the bandwheel belts (most likely the drive side). Magicman mentioned something wedged under a belt. The other thing I've had a couple of times on both my mills (usually when sawing in the snow) is sawdust buildup in the balancing holes on one of the bandwheels.

If you remove the blade and feel around under the belt, you will find small holes drilled into the bottom of the grove on the bandwheel. They will be scattered around the wheel, and they may occur in clusters. If you feel the hole, no problem. If you feel a lump sticking up above the bottom of the grove, then you've got buildup. I use a cat's paw and a flat bladed screwdriver to scrape and pry it out. When I get down near the surface of the wheel, the stuff caught in the balancing hole usually pops out. If not, I use an awl to dig it out.

While I'm poking around, I have a paint marker handy and I paint a little line on the edge of the bandwheel right next to every balancing hole. That makes it easy to check for the same problem in the future.

The vibration from this buildup is quite serious because you are constantly changing the stresses on the blade, the sawhead, the bandwheels, and the bearings.

[bandmiller2]

Not saying this is bro Powers problem but a tooth or two really set too much can setup vibrations and give you a washboard finish. Frank C.

[Magicman]

I always remove the blade at the end of a days sawing.  Without doing so even a loosened blade will trap sawdust between it and the B57 which is hard to remove.

I thoroughly clean the B57 belts after removing a blade.  There could also be sawdust under the B57 causing it to bump.  I have never had that happen, but it is a possibility.

[RPowers]

Took off the band and ran the mill with only the drive side spinning... ran perfect, smooth, and  quiet. Put the band back on and retensioned and the noise returned with the vibration being strongest on the bolt that holds the inner guide roller on. Took off the band, started checking that roller for flat spots and found that it was not turning true. When I look at it from the side and turn it by hand it is wobbling like a bent car rim. The nut is tight and the bearing feels solid, so I took off the roller and set it on a flat surface to check for warp.... nope, sits nice and flat all around. So now I'm going to check the axle bolt for bends and if that is straight I'm changing out the rollers to see if this one runs out on the other side. What a pain.....!

[jcbrotz]

Have you checked your idler wheel bearings? I have lost it twice and it sounds like its coming unglued when its bad. You can also run it with the guide roller off to check if its the bearing in it. If you do swap them from side to side you will probably need to do an alignment due to uneven wear on the rollers.

[Bandmill Bandit]

From experience with my mill you need a set of bearings in the roller on the blade guide arm. with the band off turn the roller slowly in both directions. you will likely feel a rough spot or a more resistance in a spot or 2. It wont seem like much but it is all it takes to get the harmonics going that you describe.

I replaced mine with an EBC R8 2RS with corrosive resistant seals. They are about 12 bucks each from BC Bearing   

[RPowers]

The wobble problem followed that inboard roller. Both bearings on the guide rollers are tight, but the inside roller does not free spin as smoothly as the outside one, so something in the bearing is dragging. It is like the bearing is tilted inside the roller, causing the roller to spin on an eccentric to the bearing axle. But the bearing is still tight, so I don't know what happened. any one know what size bearing it is, and if and auto parts store might have one so I don't have to wait on WM shipping?

[Peter Drouin]

I would get the parts from WM, That way you know there fit right and when you order the them get 3, One to replace the bad one and two spares. Good luck 

[isawlogs]

 If you are talking about the rollers that the blade rides on\under, then yes you can get them at the auto parts or any bearing shop. Take one out and bring it with you they will match the numbers on it.

[Bandmill Bandit]

check my previous post.

Gives brand name and part number.

A bit priceyer but bett seals

EBC R8 2RS

[Ga Mtn Man]

Hey BB, can you post a link for those bearings.  Having trouble finding them using google.

[Bandmill Bandit]

See what I can do. I picked em up at BC bearing. Not sure you have them down there but see what I can come up with.

under the bar code on the box are 2 other numbers as follows.

4 51234 678845

DC:20120608

exact copy from the box
searching now

If you put EBC R8 2RS Bearing in the google search line it should show you local suppliers besides ebay and others.

[RPowers]

Alrighty,

update.

I got the bearing ## from WM, went to the nearest specialty bearing store and got 2, which is  a good thing because there are !!!!!----->2 <----- !!!! bearings inside this roller guide, not one. So an FYI, if you buy bearings, get 2. Glad I bought an extra because my mood would really have gone south had I bought one and come all the way home.

Removed the original bearings, cleaned the race, installed new bearings, reinstalled roller. Guess what, still wobbles, not from being loose but from the roller rotating in a different plane than the bearing axle. So I checked the other roller again, still fine. I thought I'd double check again (quadruple check?) by moving switching only the roller guides and none of the other hardware in order to make sure the problem actually follows this roller. It does. If I start to engage the clutch and watch the band start turning that roller I can see that it not only wobbles front to back in reference the mill bed, but also up and down, causing the band flutter I've been seeing.

Question. Does anyone know how a heavy piece of steel can be this deformed spontaneously between uses? I'm starting to think a supernatural curse or something. Everything on the mill is in perfect alignment and tension, but this one roller is somehow out of plane with its bearing race, yet wasn't a few weeks ago when I last used the mill. I'm stumped. If I knew anyone close with a mill I would suspect a practical joke sabotage roller-switch.

[Bandmill Bandit]

Rpowers I am sorry I Didnt mention that there were 2 bearing in the roller.

FYI i did find a wide race single bearing with 3 sets of rollers in it that will replace the 2 bearings but it is not cheap and is designed to run submerged.

if you put the roller on a half inch bolt and then put bolt in a vise so you can turn it freely, with a magnetic dial gauge mounted and set to measure the deflection it will tell you if that roller was out of whack right from factory (my guess). The failing bearing just exacerbated it enough to amplify the harmonics. replace the roller is my advice. 

[drobertson]

It does sound like something got bent.  Or just came loose, pull the blade roller off again and check the 1/2" bolt that it mounts on,  see if it is bent, clean the housing and re-seat it, and go through it again, what a pain indeed,

[Peter Drouin]

WM has a new one in stock that would fix the thing. I buy the things 4 or 6 at a time. My problem is the back edge where the blade hits when the blade gets push back when I'm cutting. [Gets out of the square] I give the thing to a machinist to redress, And get a little more out of it. But a bearing, I toss them.
Good luck with your search.

[RPowers]

It does sound like something got bent.  Or just came loose, pull the blade roller off again and check the 1/2" bolt that it mounts on,  see if it is bent, clean the housing and re-seat it, and go through it again, what a pain indeed,

The first WM rep I talked with suggested checking for a bent axle bolt as well. I isolated the roller as the problem by switching the two rollers, and the problem followed the roller rather than staying with the axle bolt on the inside. I think BMB has the best idea, that the roller was whack from the start, but somehow either the roller has prematurely caused the bearing to start failing or there has been a dust buildup forcing the roller and bearing out of alignment. Either way the problem took a while to show up from when I got the mill. It has maybe 130ish hours on it.

[drobertson]

Good deal, just knowing is a relief,  it's amazing how things go good then take the dive,  hard to figure how products get sent out, out of spec, but it happens,,   

[RPowers]

So, new question. What is the best way to press bearings in without damaging them? I do'nt have a press, but I was using a tight-fit socket and deadblow hammer. Good enough?

[Magicman]

 

 
I have replaced them on the tailgate with a socket and without a deadblow hammer.   ;D

[RPowers]

Good to know, MM, thanks! I think that as time goes one there will be an inventory of certain tools and parts I will keep on hand for stuff like this. I hate to expect failure, but it happens and I'd rather be able to fix stuff "right now" and not wait on the parts dept to ship things out.

[VictorH]

If you are at home and have a drill press it can be used to press some things fairly well.  If the table on it tilts just make sure to square it up to the chuck first.

[backwoods sawyer]

I like to keep a pair of new guides in the truck as well as enough bearings to rebuild in the feild, I treat guides like saws, they do wear... 

[Red Good]

When your instaling bearings like those , make sure you push from the side with all the numbers on it , that side is heavier to acomodate the pressure of installation . Also a vise generally offers you 2 square faces . Just go slow and watch the alignment and crank away . Good luck .Red

[bandmiller2]

Everyone that messes with machinery should have a good bench vice. A vice and sockets are just the ticket for pressing bearings in and out. Bro Powers probably that guide roller wasen't turning for a wile and got worn on one side. When a mill is running sometimes its hard to tell if a guide is turning, take a black majic marker and put a mark on the back of the roller. Frank C.

[SawyerBrown]

I guess I'm just surprised this problem didn't show up right from Day1, especially since it ran smooth for so many hours. I'm thinking alien pranksters...

Another related question: how best to clean the B57 belts?  Solvent?  Physical abrasion?  I had some pretty nasty white pine tar buildup one time, used some "goo-gone" and a putty knife, but it still seemed to rough up the surface more than I would have liked. Belts still running fine at this point.

[pineywoods]

My guess is the bearings were seized for quite a while and the roller wore off flat on one side. They normally wear off more on the tooth side of the roller. It's a wonder those bearings last as well as they do. Look at it this way..The rollers ride on a blade that's traveling close to 50 mph. A 2 inch roller traveling that fast turns up some serious rpms. Then factor in water, sawdust and grit off the log.

[Magicman]

Another related question: how best to clean the B57 belts?

 
I clean mine with the wire brushes shown above.  I spin the idle side and take the belt off of the drive side.  The scraper works well if there is serious buildup.  The only source that I have found for these brushes is the Wal-Mart paint department..

[Peter Drouin]

My guess is the bearings were seized for quite a while and the roller wore off flat on one side. They normally wear off more on the tooth side of the roller. It's a wonder those bearings last as well as they do. Look at it this way..The rollers ride on a blade that's traveling close to 50 mph. A 2 inch roller traveling that fast turns up some serious rpms. Then factor in water, sawdust and grit off the log.

Or the bearing stop working race and all and the roller would still spin .
The roller gets hog out on the inside and with the band pushing up it gets cockeyed. So you get the same thing [problem] with a new bearing.

[RPowers]

The problem with a flat spot idea is that the original bearings aren't seized or trashed, and I cant find a flat however minute, and that entire roller is turning on a tilted wobble in on the bearing axle.

[drobertson]

Are you getting a new part?  I wish I could see this, but, get a new axle and see how if this one runs out. a Vise an indicator would sure be handy before you do all the adjustments on installation.  Bonifed head scratcher on this end,    david

[drobertson]

If I remember, you mentioned the blade guide is  vibrating.  Resulting in a choppy cut pattern. I had this not long ago,  If this is still the case you will need to make adjustments on the v-bearing rollers by aligning the eccentric mounting bolts, and in the process make sure it moves in and out parallel to the bed rail.  Not a bad fix, just a lil tweaking.  It will have to be done with the blade installed and tightened.

[caveman]

When I replaced the arbor bearings on my table saw last year, I put the shaft in the freezer for about an hour and the bearings in the oven at about 200° for the same time.  The bearings slid right on without force.  When the temperature equalized, the bearings fit just right.  Good luck on the repair.
Caveman

[Brucer]

Let's see, stationary shaft, guide roller wobbles. Problem goes where the roller goes.

That accounts for the vibration. Can't be the shaft. Could be the bearings. Might be a roller that's been bored off center.

Is the mill still under warranty?

[Bandmill Bandit]

I use a socket that fit the outer race of the bearing, a half inch thick 2x2 block of oak and a large C clamp in the field. In the shop I use my press.

Seized bearing don't turn and Mr powers ist the type of operator to let some thing like that slip.

Now that you have determined that the problem follows the roller I am willing  to bet that it is bored off centre just a few thou of an inch. Like maybe 30 to 50 on the minimum side. This is the reason for the dial guage test. Results are definitive.

Change the Roller. 

[Peter Drouin]

I use a socket that fit the outer race of the bearing, a half inch thick 2x2 block of oak and a large C clamp in the field. In the shop I use my press.

Seized bearing don't turn and Mr powers ist the type of operator to let some thing like that slip.

Now that you have determined that the problem follows the roller I am willing  to bet that it is bored off centre just a few thou of an inch. Like maybe 30 to 50 on the minimum side. This is the reason for the dial guage test. Results are definitive.

Change the Roller. 

One time I had an old truck, One day the front tire stop turning I was doing about 25 mi an hour, And when I took it apart I found the race had welded itself to the spindle. See the bearing seized so it spun on the shaft and welded , But that was a truck and not a Roller.

[RPowers]

Guys I really appreciate yalls input and help. I am sure that something is wrong with that roller. How things got this far down the hours on the mill without the problem becoming obvious I don't know. WM is sending another roller, and an RMA label so they can examine mine. If I can find out what exactly the problem is with it I'll let yall know. Hopefully the new part will be here in a couple of days and everything will be back to smooooth running. I have a couple jobs coming up and will be glad to have the mill cutting right again. I have this OCD thing with noise, so the buzz was driving me nuts!

RP

[RPowers]

One time I had an old truck, One day the front tire stop turning I was doing about 25 mi an hour, And when I took it apart I found the race had welded itself to the spindle. See the bearing seized so it spun on the shaft and welded , But that was a truck and not a Roller.

I'll bet that was a shock, 

[Peter Drouin]

Yes it pulled a little to the right when it happing 

[backwoods sawyer]

Where the guide had been on the mill for a good number of hours and the vibration is new, it lends its self to being a wear issue rather then a manufacture issue.

[Magicman]

This has been a very strange occurrence to say the least.   smiley_dizzy

I hope that the final answer is shared here.

[Bandmill Bandit]

it would be very interesting to know how much the measurement is out of whack and if it is a straight off centre line bore error or if it is a case of the bore being at a slight angle where the centre of the roll is in line but the one end is up slightly and the other down slightly. CNC machines are great machines but last piece cut out of a piece of roll stock can get off centre because of filings. Have seen it more than once. The CNC machine I baby sit on occasion will throw an off centre stem joint about every 4th or 5th 20ft stock piece and it is always the last piece off the stock shaft. 

[Peter Drouin]

This has been a very strange occurrence to say the least.   smiley_dizzy

I hope that the final answer is shared here.

:D :D :D :D :D :D :D smiley_dizzy

[RPowers]

After conversing via PM with Marty (Thanks Marty!), he had a new roller assy sent out last week which I received on Friday and installed Sat. The difference in how it spins on the axle is night/day. The old roller wobbled front-to-back and up-down at lease 3/32" if not 1/8" which was setting the blade into severe oscillation. The replacement spins true in all planes like a precision-machined part. So, after comparing the new roller to the remaining "old" roller it is obvious that the other one is turning out of round as well and needs replaced. It was not half as bad as the other one, but it absolutely doesn't turn true like this new one. So another part (thanks again to Marty's quick response even over the weekend) is on the way. I hope to get the second roller in by tomorrow so I can re-align everything and run some test cuts. I'll post back on that.

Thanks again for everyone's help and suggestions, and thanks to W-M for their outstanding response and support!

RP

[drobertson]

Glad to hear!  And Marty is a trooper for sure!  Nothing like finding the problem and getting it fixed. 

[LeeB]

The good folks over at wood-mizer might drop the ball every now and then, but they always pick it up running. It's just downright hard to find better customer service.

[Magicman]

Thanks for the update RP.  This is a situation where not only was the problem identified, there was also every suggestion imaginable concerning possible problems and solutions.  Everyone learns.