Love Your Lathe

Author: Spinning Brewer

A lathe is usually the biggest, single purchase in pursuit of our craft. It is a testament to their quality, that most run for many years, with little or no maintenance. One of mine, despite having a single, tube bed and being driven by a cheap, Chinese motor has been going since 1992 with little more than one, replacement, drive belt. Despite such abuse, lathes like all machinery, perform better given appropriate maintenance.

If the instruction manual for your lathe is comprehensive or you are an experienced turner, you might stop reading at this point or you may go and seek to liberate the manual from its dusty corner of the workshop. In either case, what follows is a simple outline of “what to do” rather than a set of detailed, “how to do it” instructions.

The prime function of a lathe is to hold and rotate the work-piece smoothly, at a given speed, whilst providing means of controlling a cutting tool. The heart of the beast is the motor and whilst electric motors are extremely reliable, we can forget they are but the first component of the drive train, culminating in the spindle or the bowl. A vital component is the drive belt, often hidden within the headstock and sometimes rarely remembered let alone seen or moved to a different pulley such are the marvels of electronic, speed control. A worn or damaged belt can cause vibration, which transmits through to the tool rest, making it more difficult to present a tool accurately and consistently.  

The belt still drove but caused an interesting, rhythmic shake

Whilst examining the belt, check the tension. An over-tensioned belt can also create vibration. Too slack, however, and that heavy, roughing cut will bring everything to a squealing halt.

Check that motor and headstock pulleys are still properly, aligned and lock screws remain tight.

Chuck cleaning; an old toothbrush works wonders

Chuck cleaning; an old toothbrush works wonders Finally in the fight against vibration, it’s worth checking that the nuts and bolts holding everything together, including bed sections, are tight and that sack of sand, draped over the stand, remains where it ought to be.  

Perhaps the most useful maintenance tool is a brush or vacuum cleaner. Simply removing shavings and particularly dust, at the end of a session only takes a few moments and helps prevent the tool slide and tailstock gradually getting harder to move.

A scroll chuck is pretty much a permanent part of the lathe and if, like me, you use Axminster chucks, the external annular rack that drives the scroll easily accumulates dust and dirt, which eventually hinder smooth operation. Chucks have many, metal on metal bearing surfaces and are easier and smoother to use when properly lubricated. A regular brush down followed by a quick spray with dry, PTFE lubricant keeps the chuck operating smoothly without retaining wood dust, as would oil or grease.

Brushing dust away from the carriers at each jaw change reduces ingress into the scroll and extends the time between those occasions when you have to strip the chuck to clean and then lubricate the scroll, ideally with PTFE, although light grease or machine oil is acceptable.

Tool-rest; before and after smoothing

Tool-rest; before and after smoothing If the motor is the heart, then the bed is the backbone of a lathe on which everything else, including the tool-slide and tailstock, hang. The bed needs lubricating but oil or grease trap sawdust and abrasive particles – not a good idea. The usual answer is wax and it works well – provided it is buffed up and old layers wiped off with white spirit from time to time to prevent hard, dried wax creating obstructions along the bed. A judicious smear of wax, or WD40 on other parts of the lathe help prevent corrosion if your workshop is damp or you turn wood so green it sprays moisture.

However, there are places where oil and grease are acceptable. The tailstock quill and threads are largely, protected and should be wiped clean and lubricated at intervals. The one part of the tailstock not to lubricate is the Morse taper, because any lubricant will cause a centre not to hold. If you find a centre is moving in the taper yet both male and female are free of oil and grease, examine the male, small end for damage and check the female has not become scored.  

Other things worth checking regularly are:-

  • Motor vents – if they becoming blocked the motor could overheat.
  • Wood dust on faceplates and chucks tends to gradually harden into resistant accretions, which can prevent a work-piece mounting true and secure.

Tool-rests take a hammering from sharp edges on tools. Dents can accumulate to the point where what should be a smooth traverse of the skew becomes an erratic progression along the tool-rest with an associated, uneven cut. Don’t be afraid to take a fine file to the top surface of the rest to remove any grooves. Just make sure you maintain a level surface by filing along rather than across the tool-rest. Check the surface is true using a straight edge, then smooth it with 240 grit, or thereabouts, abrasive. Finally give it some wax.

Prevention being better than cure, it is a good idea to file or grind the sharp, angular sides of skews and scrapers into a quadrant that does not damage the tool-rest.

Finally, it’s worth remembering that the workshop contains shavings and dust, not to mention white spirit, cellulose thinners, sanding sealer and wax, all of which are inflammable if not explosive, under the right conditions. Just take a few moments to check that the electrical flex and plug, are not loose or damaged.

These few words do not purport to be a  complete maintenance schedule for every lathe ever made but hopefully outline a few, simple, quick routines that  will keep your lathe running smoothly, so the shavings continue to fly, just the way you want them.