Minimax MM20 upper bearings

[Tom M King]

This is the best money I've spent on cheap, Chinese tools. I'd be rigging up a way to use a press, but have been known to use a big hammer with one of these dies, and the handle that can fit in it.

https://www.amazon.com/ABN-Bearing-D...NsaWNrPXRydWU=

I have used a hydraulic jack, under an 18,000 pound tractor, for something that wouldn't fit in the press.

edited to add: With that press die set, you can even put two on the handle. One that fits the bearing ID, and another for the pressing of the OD.

[Bill Dufour]

I bought the channlelock snap ring pliers with replaceable tips. Not noticeably less solid then a one piece pair for the size. Nice when i can grind a tip to fit and still use them with stock tips.
I have to play with them every time I use them to remember how to switch from expand and contract when squeezed.
Bill D.

https://channellock.com/product/rt-3/

[Tom Trees]

Not that I'm that fimiliar with the Centauro's, but I have studied them as good as I could find on Google searches,
seeing if I could match the design when rebuilding my saw.
It appears the design is similar.
I don't think you need to go near the plate which the bowden tension cable is attached to,
nor need remove the screw or anything like that, TBH I was unaware that there was a spring for a long time!

(someone before me was at this saw, the parts weren't in the correct order, and it had a big fall at some point too, I learned a real hard lesson about removing a split pin that
was damaged, don't ever try to get them out without a proper tool, made a rough punch with locating pin but it didn't cut the mustard, couldn't get it out after a lotta wallops with a big hammer.
Testament to the casting that it didn't break!
The other pin came out fine... for a split pin.
Just fair warning if wanting to delve further!

Back to your query
Should be a simple procedure.
Still unaware of the best way to remove the bearings with a tool that will fit inside the inner race.
Would love to get a term to search or link for the procedure.

Tom

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[Dave Cav]

Regarding heating bearings, my go to method for years has been to put them on top of a 60 watt incandescent light bulb for a couple of minutes on each side, until they are just too hot to handle.

I'll be watching this thread because I have a 4 year old MM20 with a 1" Woodmaster CT that I never de-tension......I hope Brian takes lots of pictures.

[Edwin Santos]

The number is 6207-2RS i
decided to get the Abec 3 version which is rated for higher stress since I run a carbide blade all the time. The current set lasted about five years, which seems a bit low to me.

Do you keep your blade under tension all the time, or most of the time?

[Brian Holcombe]

Thanks Tom, sounds like the upper wheel mount can be spun off and removed from the top. It looks to be the case on mine, I’ll find out soon.
E
My saw’s wheels have no access points for a standard puller so I have assumed there to be another method of removal.

Seems you all are bound and determined to discuss snap ring pliers, so here:

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[Brian Holcombe]

I never de-tension, I assume the bearings have died because of the level of tension rather than the fact that it is constant.

[Tom M King]

Your relative percentages of Knipex, and Klein, look very similar to mine.

I have used a slide hammer for bearings that can only be pulled from the inside. Search Pilot bearing puller .

Speaking of retaining ring pliers, I had to get a pair of these to get the external retaining ring off the King Pin in one of the tractors front ends: https://www.ebay.com/itm/25470971931...IAAOSwaS9fUp-C

[Tom Trees]

Thanks Tom, good to know the tool for the job

[Edwin Santos]

I never de-tension, I assume the bearings have died because of the level of tension rather than the fact that it is constant.

Thank you! I'm interested because I own the same saw, about 3 1//2 years old.
Looking forward to hearing how the replacement operation goes. Wishing you smooth sailing.

[Erik Loza]

E, My saw’s wheels have no access points for a standard puller so I have assumed there to be another method of removal…

Brian, I am sure that I used a large 3-jaw puller to remove those flywheels. It was a large puller and you inverted the jaws to go through the cutouts in the flywheel.

Erik

[Rod Sheridan]

If my slide hammer puller is too big, I drive them out with a punch, they’re going in the garbage...Rod

[Tom Trees]

On closer inspection with problem in mind referring to my comment about the SKF bearings, it appears that it does seem a bit loose on the shaft!
I'm thinking I might see if a pair of the original Koyo's might be put back to use.

With this in mind that they might be toast, I am eager to know if Erik can remember which brand bearings were a tight fit to get onto the shaft?

So glad I read this, Brian, I'd see if your wheel slides off easily without need for taking the carriage assembly off, or spin the wheel without a blade
and listen for anything.
If so, might be worth seeing if Erik can recall a good brand.

Thanks
Tom

[Erik Loza]

On closer inspection with problem in mind referring to my comment about the SKF bearings, it appears that it does seem a bit loose on the shaft!
I'm thinking I might see if a pair of the original Koyo's might be put back to use.

With this in mind that they might be toast, I am eager to know if Erik can remember which brand bearings were a tight fit to get onto the shaft?

So glad I read this, Brian, I'd see if your wheel slides off easily without need for taking the carriage assembly off, or spin the wheel without a blade
and listen for anything.
If so, might be worth seeing if Erik can recall a good brand.

Thanks
Tom

Tom, I honestly never checked. One time I looked (brand new machine) and the bearings were made in Korea! I’m sure Centauro sourced out bearings from any number of different vendors over the life of those machines.

Erik

[Brian Holcombe]

The original bearings are not impressing me much, they look
like a low cost choice. One was crunchy was just plain worn and spins loose.

I sourced SKF explorer, to replace them.

I had suspected the wheel assembly could be removed, I was correct about this. I drifted out the pin holding on the hand wheel along with a few bolts in the upper part of the assembly. After this I was able to lift out the wheel.

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Pressed out the old bearings. Pressed in the new.

I plan to clean and reapply grease. One thing I think SCM could really improve upon here is the dust collection. This saw is constantly loaded with dust after any resawing.

I think I’ll do the bottom wheel also given the quality of the original bearings leaves much to be desired in my opinion. This is a higher quality saw and they can’t spare $20 for higher quality bearings? The Ulmia, Maka, Wadkin and Omga machines I have are all top quality parts soup to nuts.