CutterComp
Plastic
- Joined
- Jul 5, 2019
I'm nearing the end of a full restoration on a 1985 Winona Van Norman SM-2000 cylinder head and block resurfacer. The table is driven by a rack and pinion setup, with an electric motor transmitting through a right angle gear box. I currently have the gearbox apart to replace the bearings and examine the status of the internals in general. It is a simple unit with a steel worm gear and a brass worm wheel. Now that I would like to reassemble the unit, I need to determine the correct grease for the bearings and gear oil for the gears.
It's relevant that the grease and gear oil share the same area inside the gear box... the splash lubrication of the gear oil must spray the grease covered bearings continuously.
So now to my question, I'm concerned about finding the correct oil and grease that will not damage the bronze worm wheel. I have the owner's manual for the machine (no service manual is available). It states that the gearbox uses SAE 80 gear oil but nothing more specific and of course, no mention of grease for the bearings because they don't expect the user to disassemble the box.
I've read about extreme pressure gear oils having additives that actually form a protective boundary on the teeth of the gears and that boundary is stronger than the brass. Therefore, instead of the boundary layer alone shearing off each with each round of meshing teeth, it actually takes brass with it. I've read that some GL-4 and all GL-5 oils have these additives. Of course, I've also read they NO LONGER have these additives and are now safe for bronze. Hard to know what to believe...
Also need to know if there is a grease that is good for packing the bearings with but safe for the bronze worm wheel because as I said, the grease and gear oil share the same real estate.
Thanks!
It's relevant that the grease and gear oil share the same area inside the gear box... the splash lubrication of the gear oil must spray the grease covered bearings continuously.
So now to my question, I'm concerned about finding the correct oil and grease that will not damage the bronze worm wheel. I have the owner's manual for the machine (no service manual is available). It states that the gearbox uses SAE 80 gear oil but nothing more specific and of course, no mention of grease for the bearings because they don't expect the user to disassemble the box.
I've read about extreme pressure gear oils having additives that actually form a protective boundary on the teeth of the gears and that boundary is stronger than the brass. Therefore, instead of the boundary layer alone shearing off each with each round of meshing teeth, it actually takes brass with it. I've read that some GL-4 and all GL-5 oils have these additives. Of course, I've also read they NO LONGER have these additives and are now safe for bronze. Hard to know what to believe...
Also need to know if there is a grease that is good for packing the bearings with but safe for the bronze worm wheel because as I said, the grease and gear oil share the same real estate.
Thanks!