Bath-time for Burnerd

It's a well-made small lathe the Grayson, 3.5inch swing over a gap bed, backgeared and screwcutting, solid, dependable, from an age when a thing well-made – even to a price – gave pleasure to maker and consumer alike. And it's a description that might easily be applied to the lathe's erstwhile owner – solid and dependable. Erstwhile because, in his 80s, he shuffled off after a lifetime in engineering, leaving his beloved little Grayson behind in his shed.
 

Grayson in its original setting

I first met him at his retirement do, the plus-one of his daughter and my future wife. He was chief designer at Westinghouse, based on the top floor of the famous Douglas building in Hanham Road, Kingswood. The shed is just a few minutes walk from that office and forms a triangle with the house he had built to his own design in 1960. The greater part of half a century going from home to office, office to home, home to shed. You can easily imagine a similar existence for the great Lawrence Sparey.

Now the Grayson lives in my workshop (read 'garage'), shoehorned in alongside my bikes and replacing an elderly Myford ML7 and a Chinese-built minilathe before that (surprisingly useful once fettled).

ML7 replaced by humble Grayson

Grayson with home-made stand and chip tray

The Grayson is better than the minilathe and not quite as good as the Myford but when you're short on space yet big on fondness and respect you'll happily swap out the ML7 and instate the Grayson in its stead. I would. I did. Now it makes chips for me and while I'm not big on the notion of the hereafter, I sincerely hope that if he's 'up there' somewhere, wandering about in a stores coat and poring over tolerances with a mic, he's somehow aware of how much the Grayson is loved in its new home.

Loved, that is, with an exception: the Burnerd three-jaw chuck that came with it. Having rested for a few years unloved in a shed, it's become a hellish wrestling match to use. A tight scroll and jaws means using it is almost a two-handed affair. In short, if you're the type of bloke who looks like Mac before he gambled a stamp, turning the scroll in this beast is hard work. Time for a CLA…

First step, remove the chuck from the lathe. Graysons have a threaded spindle compatible with Myford and so unless it's stuck, removing the chuck is a simple matter of engaging back gear to lock the spindle and giving the chuck a smart tug. Be sure to have a  bed board in place then unscrew in the conventional way.

First step: remove the chuck and wind out the jaws

Stripping varies from model to model but once it's on the bench the process is broadly similar: remove the jaws by winding them out of the chuck. Look for a register mark spanning the backplate and chuck and if there isn't one, mark it with a Sharpie, engineer's blue, chalk, scribe or whatever. Loosen the three bolts (or set screws) holding the backplate to the chuck and remove it.

Undo the bolts holding the backplate to the chuck

Inside there are three further set screws holding the scroll gear cover. Undo the screws and persuade the cover to come out – don't pry it and don't drop it when it comes out unexpectedly.

Jaws, backplate, gear cover and associated screws

Undo the threaded pins located alongside each chuck key gear, remove them and their respective gears. Now you can remove the scroll. Insert a brass drift through the front face of the chuck and give the scroll several smart raps – you might have to work at it to shift it.

Use a brass drift…

…to remove the scroll

With the scroll removed the chuck is reduced to its constituent parts. Give everything a wash and brush up in a bath of paraffin, brake cleaner or some other suitable thinner.

Paraffin bath for Burnerd

Allow it to dry (you can help using paper towels), oil sparingly (some prefer grease – your choice) and reassemble being sure to line up any register marks, replace the chuck key gears in their numbered housings etc.

Be sure to correctly reinstall numbered parts

Reinstate the chuck on the lathe. Now you'll have a chuck that is free and a pleasure to use.

Spruce chuck back in place

Incidentally, always store a chuck jaws down (that is, standing on its opened jaws). It's counter-intuitive but there's less chance of upsetting the backplate register and reduced opportunity for foreign matter to find its way into the scroll.

Coming soon: the Royal Enfield 500 Twin my father-in-law owned and loved as a young man (yes, despite a background in engineering!)