Smart & Brown

The lathe shown in the picture at the top left is my latest acquisition, a Smart & Brown Model A.  I remember using one of these in my teens when I was killing time waiting for a place at a training school.  It is a tool room quality machine and very complete.  It came with both fixed and travelling steady; disc and ring collets complete with closers; 4 way toolpost; a good number of collets that I've been able to add to so that I have an almost complete set in 1/64th from 1/64th to the maximum 3/4".  Recently I was able to purchase a special headstock centre off eBay; this allows me to machine between centres.

The cross slide lead screw had a lot of backlash and I purchased a replacement direct from Bracehand, see link at side.  This has cured the problem and now holds the cross slide under all conditions tried so far.  I do have some backlash on the compound slide and in due course will consider replacing screw and nut.  One other source of trouble has come to light recently one of the backgear helical gears has become damaged almost certainly through past owners engaging backgear without stopping the machine!  I am currently investigating the effort involved in replacing this gear.  I have managed to locate a new replacement bronze gear but the cost is beyond my current means.

I have just started a project to construct a quick change toolpost.  It is based on the Hemingway kit but I have beefed it up to match the original S&M toolpost.  I am carving it out of a block of mild steel some 18" x 4" x 2.5".  So far I have cut off two pieces one for the main body and the second for the clamping plate.  I have drilled some holes and bolted the two pieces together and am currently machining the block to near final size.  Once I have achieved near final size I can then drill out all the various holes to final size and then transfer to the Tom Senior mill and cut the dovetail for the tool-holder.  The tool-holders will be designed to take up to 16mm square tool bits.

One variation to the Hemingway version will be a change to the method of adjusting the tool height, I have yet to finalize my method but it should prove nicer in some respects.

I have now reached the point where I have the blocks mounted on the Tom Senior mill and have yet to adjust the head to a true vertical position.  Some machining of the dovetail has been made but I have now stopped machining in order to replace the motor for a single phase unit and an increase in power from 1HP to 1.5HP.  I have to fill in two mounting holes and re drill in a new location.  I have to fill the original holes as the new ones will machine partly into the old holes.

At the same time I have re jigged the built-in luminaire unit.  The original had a 440V transformer with a 48V secondary.  I have changed this to a 240V toroidal unit with a 12V secondary.  This enables me to use standard auto lamps, the one I'm using is a stop lamp 21W and gives out a lot of light, and they are cheap to buy.  At the same time I have taken the option to rewire the unit as the original  wiring showed signs of crazing, a sure sign of over-heating.