Blade guide bearings

[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.