Cold Weather

Thought I would brave the cold today and do some milling. At the end of the first light pass I realised the bearings were making an unusual noise. Popped the drive belt off and double checked it was not the motor and had a feel of the main bearings. Generally felt ok but once or twice the normal drag was briefly much reduced. Began to wonder if it was too cold at 3C for the grease and the rollers were just sliding. Filled a four pint milk bottle with hot water and placed it under the head. Wrapped the whole lot up in a sheet. After an hour it was 8C at the top of the quill and 13C at the bottom. Ran up slowly to full speed and the sound was back to normal. Not sure I would have noticed the sound change if it had been a geared head though.

Strange thing to happen as the temperature was not very low for most types of machinery. The motor bearings would have similar grease in them. If you are concerned enough to regrease the spindle, use a high melting point lithium grease, not moly grease that is available from Halfords for car wheel bearings.

Cold has that effect on gearbox oil in the Centec

Turning tools have a greater propensity to chatter in these temperatures although I think it’s my teeth actually.

Martin

I put my chinese diesel air heater on about ten minutes ago. The workshop will be warm in about another ten minutes - but that will not include the machines. I don’t expect the workshop will have cooled overnight to less than about 5-6 degrees, so wouldn’t expect any trouble by the time I get ready to machine some parts.