When and which LUBE to use for MK3?  

Re: When and which LUBE to use for MK3?

Here’s an excellent write up on how to properly care for your rods and bearings: https://prusacommunity.com/set-your-bearing-straight/

Re: When and which LUBE to use for MK3?

Personally I recommend Singer sewing machine oil for the rods and bearings a drop or two once in a while (Over 40 hours or more or if it has not been used for a while), and a wipe with a clean lint free cloth to remove excess and the build up of dust. I use a precision oiler, press the button and one drop of oil is dispensed.

Why oil?. Basic grease is basically oil in a carrier substance or soap emulsified with oil. The oil is released from this mixture due to heat which is produced by the bearings running along the rods.
Now when was the last time you felt heat from the bearings on a 3d printer?.
Different grades of grease are more or less liquid in state but all suffer with high viscosity which you don't really want on a 3d printer.
https://en.wikipedia.org/wiki/Grease_(lubricant)

Hope this is informative in your decisions going forwards.

Re: When and which LUBE to use for MK3?

Now when was the last time you felt heat from the bearings on a 3d printer?.

I don't know. I truly never felt my bearings while the printer was operating.

Re: When and which LUBE to use for MK3?

Just to add, the linear bearings are known as recirculating bearings, as the balls roll to the end and return round a loop and come back to the beginning.
If the grease is too thick, they can't roll freely and this causes the bearings in contact with the rod to slide rather than roll, also there should be no additives in grease like molybdium disulfide or PTFE as this can build up on bearing and rod surfaces and whilst it will act as a lubricant, it can also cause varying stiction along the length of the rods, not a problem on relatively slow moving highly loaded surfaces, exactly what a 3d printer is not, the printer is a light load high speed mechanism which is more suitable for oil lubrication, but will require a maintenance regime, if your the sort of person who prefers to fit and forget, then get a light lithium grease and don't go overboard with it, too much grease is as bad as none at all.

Re: When and which LUBE to use for MK3?

Personally I recommend Singer sewing machine oil for the rods and bearings a drop or two once in a while (Over 40 hours or more or if it has not been used for a while), and a wipe with a clean lint free cloth to remove excess and the build up of dust. I use a precision oiler, press the button and one drop of oil is dispensed.

Why oil?. Basic grease is basically oil in a carrier substance or soap emulsified with oil. The oil is released from this mixture due to heat which is produced by the bearings running along the rods.
Now when was the last time you felt heat from the bearings on a 3d printer?.
Different grades of grease are more or less liquid in state but all suffer with high viscosity which you don't really want on a 3d printer.
https://en.wikipedia.org/wiki/Grease_(lubricant)

Hope this is informative in your decisions going forwards.

I already lubed my CR10 threaded rods with sewing machine and had positive results, except that sewing oil is "dust collector". Thought that some "special" lubes are offering better results.
I got like 80ish hours on my MK3.

Re: When and which LUBE to use for MK3?

That is the only downside with using oil, but the seals push it to the ends where it is easy to wipe off.