Delta 31-780 B.O.S.S.

[Ray Newman]

Gents: I have a (probably 20 year old) Delta 31-780 Bench Operating Spindle Sander. Do not use it very often, but when I do it does work well.

Manual says to repack/change the bearing grease every 100 hours, but does not specify type of grease. Anyone have any idea as to what type of grease to use?

Thanks in advance....

[Jim Becker]

I just used mine today...my use is also infrequently, but when it's the right tool...it's the right tool. :) I honestly didn't know about the maintenance you mentioned as I bought mine used and don't have a manual. 'Looking forward to any advise you receive accordingly.

[Ray Newman]

Jim Becker: Delta 31-780 on-line manual -- https://www.manualslib.com/manual/725746/Boss-31-780.html#manual

[Ray Newman]

Jim Becker: Took off the plastic gear cover and found that the motor shaft worm gear is metal, the spindle gear appears to be Nylon with very little lube remaining. Local auto shops and response on another woodworking site advised applying a silicone grease for the Nylon.

I purchased NAPA "Sil Glyde" grease, part # 765-1351, 4 oz. for US $7.95.

The screws holding the plastic gear cover are #6-32 x 1/2" and are easy to misplace. Luckily, I had a magnetic tray to catch them! if you loose one or both, drop me a PM here as I have some in my machine screw cache.

[Bruce Page]

Thanks Ray. I'll check mine the next time I pull it out.

[Jim Wiskus]

Jim Becker: Took off the plastic gear cover and found that the motor shaft worm gear is metal, the spindle gear appears to be Nylon with very little lube remaining. Local auto shops and response on another woodworking site advised applying a silicone grease for the Nylon.

I purchased NAPA "Sil Glyde" grease, part # 765-1351, 4 oz. for US $7.95.

The screws holding the plastic gear cover are #6-32 x 1/2" and are easy to misplace. Luckily, I had a magnetic tray to catch them! if you loose one or both, drop me a PM here as I have some in my machine screw cache.

Hi Ray & Merry Christmas! I too picked up some of the Sil Glyde yesterday. Is there any rule of thumb as to how of the Sil Glyde to put in the gear box? I did coat both gears and left a couple dabs on the inside of the black cover. Also, I would like to mount the sander on a stand. Delta's 50-780 is no longer available as an assembly, and piece by piece would cost prohibitive. Any thoughts on another? I understand too that I will most likely need to cut the horizontal supports and drill new holes. I am just trying to find one that will involve the least amount of modification. Thanks so much! Jim Wiskus (Council Bluffs, IA)