Blade guide bearings

[Bruno of NH]

How long should they last.
Mine went out today on the adjustable guide arm side with 234 hours.
I ordered some more today. 
My friend that mills 3 towns over is giving me some till mine come in.
I will replace his , when mine get here. 
I wish Woodmizer would have told me when I got the mill to have extra on hand. 

[Magicman]

It seems that you can get good ones and bad ones so I can't say how long they will last.  I have had a few that only went a few hundred hours like yours, but then again, I have had some to last thousands of hours.  I just replaced my blade guides last month and they had gone 4 years.
 
Tail gate repairs

[donbj]

How long should they last.
Mine went out today on the adjustable guide arm side with 234 hours.
I ordered some more today.
My friend that mills 3 towns over is giving me some till mine come in.
I will replace his , when mine get here.
I wish Woodmizer would have told me when I got the mill to have extra on hand.

Were they the greaseable type?

[Bruno of NH]

Not greaseable 

[Bruno of NH]

Can you get greaseable ones ?

[donbj]

I replaced mine at 1000 hrs and they were still good actually. They were greaseable. Your shaft they mount on has to have the grease zerk on the end to grease them though. The replacement bearings WM sent were the non greaseable sealed bearings. The only difference between the two is the greaseable ones have one side with no seal on it and there is a small notch on the end of the inner race to let grease pass through to the bearing when it's greased. All I did was take my dremel with a cutting wheel and make a notch like the original, remove the seal and install. Open sides of the bearings face each other in the roller guide.

If your shafts don't have provision to grease the guides you can carefully remove one seal and make sure the new bearings have sufficient grease. It's surprising how little are in them sometimes. I would take a seal out, fill it with grease and put the seal back in and install. It should make quite a difference in longevity. The seals are easy to remove and reinstall if they are the rubber/plastic ones, just be careful.

[Silverfoxfintry]

Bearings are a consumable item and all require replacement at some time.
Beware of over greasing bearings. It makes them run hot until the excess has worked out of the bearing.
I suspect that you are paying a premium ordering bearings from the mill manufacturer.
Measure the bearings in your guides and go to your local bearing shop.
Or look online. 
DONT purchase generic, unbranded bearings. SKF, RHP, KOYO, ETC.
Are all good and if you get bearings with rubber seals will last a long time as long as you don't pressure wash them.
I keep a complete set of bearings for my sons mill and if one fails it's a quick job to change one out. Minimum down time! No rushing about trying to find replacements.

[Bruno of NH]

I had my other mill 5 or 6 years and never had a issue with them.
I know bearings need to be replaced but I thought they would last at least 500 hrs.
I have a complete new guide coming and 10 bearings from Amazon. Name brand.

[YellowHammer]

They are not greasable, but if you give them a shot or ATF on either side with a hand sprayer before sawing, it seems to help them last longer.  I don't know if they are truly sealed well, and that lets the water lube system slowly gets past the seals.

I have the same experience as MM, some last a long time, some not so much.    

[Bruno of NH]

Mr.Yellowhamer 
I will start doing that
I have used lots of washer fluid this year as I have sawn 6 days a week all winter.

[Magicman]

Don't fret over it Jim.  Yours was just a fluke/defective bearing and not the normal.  Also, forget the idea of greasing.  Yes it can be done and some do, but you have better things to do.

[WDH]

you have better things to do.

Terri Clark - Better Things To Do (Official Video) - YouTube

[Brad_bb]

My first set lasted about 250 hours.  I say about because my mill didn't come with an hour meter and I didn't put one on until after I put the new guides on. When I ordered the replacements, the woodmizer salesman I talked to on the phone sounded like 200-250 hours was about normal.  Not sure if they really know. The first one failed(on the adjustable guide arm), so I just replaced that one. The other one failed not long thereafter- maybe 20 hours.  They failed by just no longer rotating.  Now I keep a new set on hand.

[Bruno of NH]

I'm back up and running thanks to Rick at Wrightway Sawmill for giving me some bearings.
I will change them out at 200 hrs from now on.
Please suggest any other parts I should keep on hand.
I have the loader valves and spare wheel belts.
I will have bearings when they come in.

[Magicman]

Personally, I never replace the bearings unless they go bad.  Most times they well go thousands of hours.

[GAB]

I'm back up and running thanks to Rick at Wrightway Sawmill for giving me some bearings.
I will change them out at 200 hrs from now on.
Please suggest any other parts I should keep on hand.
I have the loader valves and spare wheel belts.
I will have bearings when they come in.

To your comment: "Please suggest any other parts I should keep on hand." I offer the following:
A complete set of spare belts: up/down motor belt, Feed motor belt, and drive belt.
Enough fuses to be able to replace those that give up the ghost.
Hydraulic fluid and both log loader velocity fuses.
A seal kit for the blade tensioner.
I'd have to check my sawmill toolbox to see what all else I have in there.

As an aside I destroyed a velocity fuse trying to scoot a log over with a peavey while on the loading arms.  I then added a piece of 1" pipe (home made bushing)(I can't recall the exact length) on both sides of the log loader cylinder when the log loader is down.
I removed the small bolt slid out the 1" diameter pin then put pin back in with new bushings on both sides of the cylinder mount then put the small bolt back in.  Have not broken another velocity fuse yet.
Gerald

[Bruno of NH]

Gerald 
Do you have pictures ?

[GAB]

Gerald
Do you have pictures ?

Jim:
Yes I do somewheres.
I have never posted a picture on this site so it would be a major learning curve for me.
Me and putters do not get along very well.  They do not work as my dad blame mechanical mind thinks they should.
The pictures of RAY with his box of grits which my wife took were posted by Mr. Davis.
Gerald

[WDH]

If the pics are downloaded to your computer, it is easy.  I can walk you through it. 

[ladylake]

Personally, I never replace the bearings unless they go bad.  Most times they well go thousands of hours.

Same here, give them a spin, if noisy replace them. No sense in wasting money replacing good bearings.   Steve

[Magicman]

Please suggest any other parts I should keep on hand.

Jim, go easy on stocking up with a bunch of spare parts that you may never need.  Even though you have a new sawmill you may still have an odd failure (such as you just had) from time to time but Wood-Mizer ships plenty fast so you will never be down for any appreciable length of time.

[YellowHammer]

I keep at least one spare guide roller on hand, as well.  So if a bearing goes bad, it will sometimes partially lock up and not roll freely, and the band will slide against the guide roller, and put little notches in the shoulder, or a flat spot the surface.  Even if the bearings are replaced with the existing roller, the notched rollers will damage the bands and prematurely break them.  So a new spare guide roller instead of a couple of prematurely broken bands is part of my inspection checklist.

In the grand scheme of things, a set of bearings and a spare guider roller don't cost much, and can be changed in a few minutes, and I can be back top and sawing in a hurry.  While doing the repair, I'll call up WM and order a new set.  

[donbj]

Yours was just a fluke/defective bearing and not the normal.  Also, forget the idea of greasing.

Due respect, how do you know that it was a fluke/defective? Gotta be careful making a claim like that. New sealed bearings failing in short order is not always a defective bearing. How does one know if they have sufficient grease in them? It takes 5 minutes to do a couple bearings when purchased.

[Larry]

The bearings fail because the grease is washed out by the lube.

Use just a little water and they last a long time.

Use more water and they don't last as long.

Use lots of soap with lots of water and the life span gets shorter.

Add in windshield washer fluid and the mix becomes lethal.

I think I get the best bearing life with very little water flow and a big glug of cotton spindle lube.  No soap.  In the winter I do use windshield fluid, but not much.

[Magicman]

how do you know

How do I know?  I am not some kind of expert but I do have over 18 years of sawing under my belt and I certainly know that a blade guide bearing "going bad" is not normal.  If it failed in 200 hours, it was a fluke, defective, or whatever else it might be called.  Bearing failure does not have to be a roller, ball, or a race failure, but it could be.  The bearing is a unit and if it came from the manufacturer mechanically perfect but with not enough or improperly greased it was defective.

[donbj]

but with not enough or improperly greased it was defective.

That's my point. A quick 5 minute check on a new bearing and it's fixed

[Magicman]

Correct, you have fixed a defect.  

As I said somewhere else today: "there are two sides to every coin, but it is still the same coin"  :

[donbj]

Correct, you have fixed a defect.

Yes, and would you rather install a bearing with a defect or one with the defect fixed and hopefully avoid having to change it out in another 200 hours?

Anyway, each his own.

[btulloh]

New sealed bearings failing in short order is not always a defective bearing. How does one know if they have sufficient grease in them? It takes 5 minutes to do a couple bearings when purchased.

I'm learning something here . . . you can grease sealed bearings?

[dirtmotor]

You can , just carefully remove seal and grease and replace , but like someone else said you can over grease and cause bearings to overheat .

[Magicman]

Most assuredly I will not be opening new sealed bearing and squirting grease on the odd chance that they might not be properly greased from the manufacturer.

I just had a Wood-Mizer Field Service done and Bob replaced my blade guides (with new ones that I already had) that had been on the sawmill since my last Field Service which was done 4 years ago.  Of course I kept the old guides and I also have a couple of bearing kits for a quick replacement if I have a bearing failure.

[21incher]

Wondering if it may have something to do with the fact windshield wash fluid  contains alcohol and alcohol can work through seals that will hold grease dissolving and contaminating the sealed in lubricant . I use alchohol as a degreaser.

[YellowHammer]

As people know, I'm a big fan of Spindle Cleaner, or any other water/oil emulsion additive.    Just as it keeps the bands oiled, nice and shiny, it lubricates the shoulders of the band rollers to help prevent "scrubbing" when sawing hard, and I'm convinced it also contributes to the longevity of the rollers and bearings, much like @Larry mentions.





  

[John S]

My first LT40 had about 670 hours and my current LT40 Wide has just over 350 on it. no issues with blade guide bearings.

[Weekend_Sawyer]

I had my second bearing failure in 18 years recently.
My guide rollers have 2 stacked bearings in them.
Both failures were the inner bearing on the exit side of the mill.

I have one spare roller with bearings ready to put on so after replacing I  knocked the bearings out and replaced the bad one and put that roller on the shelf as the spare. Works for me.

Jon

[GAB]

Jim:
Per your request.
This is the velocity fuse I broke.



This is the broken piece with the extraction tool.



New extractors I purchased to remove the broken piece from the cylinder.
The one that fits for the velocity fuses is in the sawmill tool box.



The next two pictures show the two 1" pipe spacers I added to keep the hydraulic 
cylinder centered so that the velocity fuse will not hit the side of the opening for it.

[donbj]

Most assuredly I will not be opening new sealed bearing

Oh come on, I bet you went out and checked one out.;D Just kidding. I enjoy following your adventures.

[Bandmill Bandit]

There is a reason I ONLY buy SKF and NTN bearings. You NEVER need to even think about opening one of those up to ADD grease. 

Cheap bearings indicate of a chincy operation!

[teakwood]

Most assuredly I will not be opening new sealed bearing and squirting grease on the odd chance that they might not be properly greased from the manufacturer.

I'm with Magicman on this one, the bearing company probably knows better than the average Joe how much grease is adequate for perfect roller functions. I think they do their homework  

[Bandmill Bandit]

I do own a grease needle to add grease to sealed bearings where the seals are compromised as a result of wear and tear from use. It is a bandaid solution to extend the life of the bearing to get through a job and then repalce the bearing.

If a new bearing requires grease BEFORE it is installed it isnt worth the powder to blow it out the shop door. OVER greasing bearings with cheap grease is a far more costly method of damaging bearings long before they are designed to fail, than under greasing will ever do. Good sealed bearings last a long time. 

There are people that will disagree with me, BUT for bearings I buy a high grade best quality silicone Marine grade of grease in a case lot 12 tubes that runs about $150 bucks for the case. I use a max of tube and a half a year on my saw mill. I only grease till I HEAR the grease"squeak"! NEVER more that.  

I do not want to see copious amounts of grease squeezing out all over the machine. It attracts dirt like glue and causes premature wear! IF I do over grease I clean with brake clean to stop dirt attraction before it starts.  
 
For bushings I use a regular marine grease that runs about 4 bucks a tube and I grease the same way; till I hear the grease "squeak".          

[terrifictimbersllc]

Regarding taking bearings out and putting them back in....

I wouldnt know how to knock out a bearing from the guide roller without probably damaging it.  

Putting a new one in, I use the right size socket which contacts only the bearing outer rim.  

Knocking one out, because the roller opening is smaller on that side, I am punching on the seal/ball bearings themselves.