Be careful with the thrust bearings on a Centauro MM16 bandsaw

[Richard Coers]

I have the original design guide bearing and thrust bearing on my machine. The sleeve bearing on the thrust bearing had almost froze up. I took it out of the bandsaw, added oil and just about had it in perfect shape when my oily fingers dropped it. Pink, the hardened thrust surface broke off. WHAT????? They make that wheel and stub shaft from some kind of cast steel and the stub shaft snapped right off. It took some work to get the stub shaft out of the mounting shaft. I had to drill a hole from the back side and tap it out with a punch. Bought some original Devcon Epoxy and found the exact pattern in the shattered steel. Put on a dab of epoxy and felt the shaft find home. Let it sit for two days. Reassembled this morning and the epoxy held during the light pressing to get the bronze bushing back into the mounting shaft and made a half dozen cuts. No runout and it held. Fingers crossed!!! So be careful and work over a bench if you ever take yours off!

[Jacques Gagnon]

Richard,

Good information, thanks. The side bearings are also prone to breakage when dropped on a concrete floor.

[Erik Loza]

Crazy… This is the first time I’ve heard of such a failure. Going down memory lane, I recall a customer with an S45N that shared pics of his fence locking lever snapping at the shaft. This was piece was made of bronze (?). Anyhow, the core of the shaft was like metal powder. Like, the smelting process was incomplete but there was enough solidness to cast the part. All the bits and pieces on most machines are just sourced from various OEM suppliers, so I guess you just get a lemon once in a while.

If it was my machine, I might take this as an opportunity to upgrade that thrust bearing to one from Space Age Ceramics.

Erik

[Jim Becker]

I kinda think that Erik is correct.

That said, I think it's a good thing that we are "over protective" of not dropping machine components as we do maintenance or function changovers. Collets are a biggie...in the CNC world, you drop one, you replace it. It doesn't take much to seriously mess up some things when they hit the floor from a few feet up. Using a container when disassembling things is a good way to help with this...a plastic one.

[Richard Coers]

I'm back up and running. The Dev Con epoxy survived pressing the thrust bearing and wheel assembly back into the adjustable mounting shaft and run for about an hour today. I've always set the thrust surface so it just kisses the blade at idle. This is definitely some kind of iron casting since it is incredibly hard and brittle. It did have a really fine particle size and I had to work at finding the exact mating pattern.

[Tom Trees]

I stuck a bearing on mine, as it was absent for a long time,
(tried learning to weld whilst filling the cuts in the face, and the same thing happened)
The upper one was successful(ish) though!

I fitted a bearing onto mine, though not this one from the motor, but a smaller one, so the inner race is against the face of the shaft instead.
This required drilling for a bolt which wasn't easy, and some bit of pipe or whatnot for a bushing.
VFD bandsaw.JPGSAM_7980.jpg

"I got the idea from a magazine" ...well another forum actually,
Have a look at Bob Vaughan's post for some possible inspiration.
https://ncwoodworker.net/forums/inde...and-saw.61462/

All the best
Tom

[Wes Grass]

'Powdered Metal', literally metal powder compacted in a mold and then sintered in a furnace. Lots of things made this way. Nothing inherently wrong with the process... a good chance the connecting rods in your car engine were made this way.