The Leinen apron is noisy

June 23, 2013 in machine overhauling, boley leinen LZ4SB

After mounting again the lathe apron we tested it and find a slight chatter when turning the hand wheel in one direction. Some time of careful inspection convinced us that the the source of the noise is one of the gears of the train. We didn’t check all the train gears before because to disassemble this section of the train we need a couple of special wrenches. Now it is mandatory to build them: a pin wrench socket for the shaft of the noisy gear and a special screwdriver to extract the rod that supports the switch mechanism.

Clean and inspect the Leinen lathe apron

April 13, 2013 in machine overhauling, boley leinen LZ4SB

The apron Following with the overhauling of the Leinen LZ4SB now the star is the apron. The Leinen apron is double walled and all the mechanisms run in an oil bath. It has an clever mechanism to stop the transversal and the longitudinal advances when there is too much torque. This allows to work with adjustable stops during automatic turning or facing operations. Power transmission between the feed bar and the apron is done through a worm drive placed inside the apron case.

Recover the Leinen lathe original look

March 15, 2013 in machine overhauling, boley leinen LZ4SB

An important task during the Leinen lathe refurbishing is to recover it’s original aesthetics. This a time consuming process if you want a quality result. These are the main tasks:

Clean and remove rust of surfaces
Polish the surfaces
Prepare the surfaces to be painted
Paint

Lathe tools tray

December 31, 2012 in machine overhauling, boley leinen LZ4SB

The factory pictures of the lathe show a tool tray and stand for the blueprints. We made a tray identical to the original. The work of steel sheet, for which we have no material or tools, was made by Lázaro Metalpress. The result, once painted is this: The tray was covered by a neoprene sheet of Plàstics Pujol.

New electrical wiring

December 31, 2012 in machine overhauling, boley leinen LZ4SB

Altivar 312The lathe comes with an classical electromechanical wiring. It has an original Bauknecht 2 Kw and 3 speeds motor (720, 1450, 2880 rpm) . It was originally a 3 phase 220 V motor that in some moment was rewound to 380V. It has two speeds in a dahlander winding and an additional speed in an ordinary winding. Note how big and sturdy is the motor enclosure because of the number of speeds:

Review the two speed reduction gearbox

December 26, 2012 in machine overhauling, boley leinen LZ4SB

The Leinen lathe comes with a two speed 1:1/1:8 reduction gearbox that can be operated while the machine is running. It works by using a multiple disks oil bath clutch. We disassembled the gearbox to check its condition. The reduction has a very thick deposit of oil after years without maintenance. Disks are in good condition and shaft seals are a bit worn. The following image shows the reduction set of parts after unassembling it.