Grease for Gears in Gearboxes

[trash treasure]

12 hours ago, dikman said:

Don't forget that gearbox oil is generally used in enclosed sealed gearboxes so the gears are essentially running in an oil bath. It doesn't matter if it gets flung off as it is constantly replaced on the gear surfaces. Unlike sewing machine gearboxes.

This is absolutely right - Please do not think to use any kind "gear oil" in a sewing machine gear case - They are NOT sealed like that, and all you will do is make a mess! What works for a bush hog, is NOT what's needed in a sewing machine. Either use some kind light grease, that will stick to the gears, or just take the gear case off, and oil regularly.  One grease I've found that works pretty well, if you go the grease route,  is "Super Lube" synthetic grease - It's a clear grease, with no smell, and it seems to hang on the gears fine :

https://www.amazon.com/Super-Lube-21030-Synthetic-Grease/dp/B000XBH9HI/ref=sr_1_3?crid=102Q4WNC2JWML&keywords=super%2Blube%2Bgrease&qid=1658919014&sprefix=super%2Blube%2Bgrease%2Caps%2C938&sr=8-3&th=1

[Matt S]

On 7/26/2022 at 8:20 PM, sbrownn said:

Why would you use anything else?

That's what it is specifically designed for...lubricating gears.

 

On 7/26/2022 at 11:33 PM, dikman said:

Don't forget that gearbox oil is generally used in enclosed sealed gearboxes so the gears are essentially running in an oil bath. It doesn't matter if it gets flung off as it is constantly replaced on the gear surfaces. Unlike sewing machine gearboxes.

 

22 hours ago, trash treasure said:

This is absolutely right - Please do not think to use any kind "gear oil" in a sewing machine gear case - They are NOT sealed like that, and all you will do is make a mess! What works for a bush hog, is NOT what's needed in a sewing machine. Either use some kind light grease, that will stick to the gears, or just take the gear case off, and oil regularly.  One grease I've found that works pretty well, if you go the grease route,  is "Super Lube" synthetic grease - It's a clear grease, with no smell, and it seems to hang on the gears fine :

https://www.amazon.com/Super-Lube-21030-Synthetic-Grease/dp/B000XBH9HI/ref=sr_1_3?crid=102Q4WNC2JWML&keywords=super%2Blube%2Bgrease&qid=1658919014&sprefix=super%2Blube%2Bgrease%2Caps%2C938&sr=8-3&th=1

In the 4 years since I made that initial suggestion I've stripped a few more machines down and run several million stitches. Some machines have enclosed/sealed oil baths around the pinion gears, complete with watchglasses, gaskets and fill plugs. Others are completely open to the elements, where anything liquid will dribble onto your knees if the drip tray isn't installed. Many run halfway between, with closed (but not sealed) boxes to mostly keep the schmoo in and the crud out. Still others have pumped oil systems, but we don't use those much in leatherwork.

As others have said gearbox oil is designed for cars where the gears, undergoing significant pressure and wear that isn't seen in a sewing machine, are kept wet in a bath. It's relatively high viscosity oil but not, in my humble opinion, high enough to prevent it getting flung off unsealed pinion gears. When I suggested gear oil back in 2018 I was overthinking things. These days my machines with oil baths around the pinion gears get white sewing machine oil, same as the rest of the machine. Unsealed gears get lithium soap grease (and a complete strip and regrease if it looks manky). I like simple.

[dikman]

Simple is good. White lithium grease may work, just a light coating to minimise fling-off, the idea of motorcycle chain oil is good but I've got several different types that I've tried on my bike and all but one tend to throw off and make a mess. The one that works best on the bike is Motul brand, minimal fling.