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plunger
05-01-2019, 11:00 AM
I am refurbishing an old 4x6 bandsaw to a permanent vertical bandsaw. Problem is it is in a million pieces and I am trying to figure it out.

On the shaft for the worm and wheel I see it has 6202 bearings as well as an oil seal. Do the bearings need to be oil by the gearbox oil via splashing. Or could they be sealed bearings and then there would be no need for the oil seal. I would think there is a chance of the bearing being damaged by grit from wear from the wheel and worm or is this unlikely.

Rich Carlstedt
05-01-2019, 01:01 PM
Well, The worm needs oil or lube and non-sealed bearings are cheaper for the manufacturer.
I have no problem with using a sealed bearing in your position as it s a low RPM situation.
The seal on the bearing should suffice to retain the lube "IF" the lube is thick or stiff ( high viscosity ) IMHO

Rich

nc5a
05-01-2019, 01:16 PM
Plunger,

I have an old 4X6 bandsaw that I recently repaired with a new worm and wheel. I can say based on observation that there isn't a lot of splash going on in the gear box at medium speed which is where I run my saw. Also, my saw has 2 sealed bearings for the worm along with an oil seal and a spacer. And sealed bearings for the wheel and no oil seal. If you can, install a seal on the wheel shaft. I didn't on mine and it weeps a little bit.

Duffy
05-01-2019, 05:08 PM
Since the worm-wheel system is low speed, why not abandon the idea of oil bath lubrication and apply a coating of extreme pressure grease?

plunger
05-01-2019, 05:37 PM
I dont mind filling the gearbox with oil,I just was wondering if the oil would dissapear past two sealed bearings so dont see a need for it. It looks like these seals are about ten dollars each so by the time Ive bought the ten bearings to replace all the existing bearings it becomes an expensive refurb.I dont want the oil to escape and cause the worm and wheel to seize.

nc5a
05-02-2019, 12:44 AM
Plunger the answer to your question is yes, the oil can and will leak past cheap seals and sealed bearings. It took my worm and wheel 39 years to seize up which prompted me to have a look see. So it took a long time to get to look like they do in the photos. Also, I had no indication there was a problem until the band saw seized up during a heavy cut.

https://i.imgur.com/sBqz8AB.jpg

https://i.imgur.com/skxRxIm.jpg

https://i.imgur.com/XY7mzNP.jpg

https://i.imgur.com/uQYREpA.jpg

vpt
05-02-2019, 07:40 AM
I had to replace the bearings in my 7x12 because of the oil leaking out of the gear box. I think it was something like $24 for the bearings.

https://i.imgur.com/6dQJfmY.jpg

https://i.imgur.com/9Q75qUM.jpg

My bronze gear looked about the same shape as nc5a's. I stuck it back in and ran it. Still going to this day.

https://i.imgur.com/QjFvtxo.jpg