Inside the lathe B2 & C3
My second Pittler B2 came dismantled and unbolted from the heavy cast iron tray with the headstock removed for easy lifting, it gave me the opportunity to see some of the hidden parts such as the clutch and the saddle adjustment. Below left shows the nameplate removed to show the clutch. It's a four tooth Dog clutch that is closed by the lever on the front of the lathe or pushed open by the rod under the bed.
The clutch and the end of the rod that pushes it open can be seen by unscrewing the nameplate on the back of the headstock
The phosphor Bronze nut and adjustment screws
The automatic stop for the saddle
Left: part of the rod that runs along under the entire length of the lathe bed can be seen on the left, this has an adjustable lug which can be locked onto any part of the rod and is used to push the clutch open when the saddle reaches it and thus automatically stops the lead-screw at a given setting. My lathe has one on the tailstock side also as it is fitted with tailstock drive mechanism.
Also visible is part of the saddle showing two of the adjustment nuts as mentioned below.
Top right: the phosphor Bronze lead-screw nut is surprisingly large. There are two small & two large screws, the latter of which were immoveable so I didn't risk trying to force an adjustment on them. These are presumably used to take up any wear in the nut.
To access this the nuts shown above under the saddle have to be undone, the pair of jibs then easily slide out allowing the saddle to slide off. Below shows both sides of the pressure plate when withdrawn from the saddle, this lifts off to expose the nut. One end of the centre part of plate is slightly thicker than the other.
Above shows the underside of the pressure plate and how one end is slightly thicker than the other
The pressure plate which adjusts the tightness of the saddle on the bed
The adjustment jibs
The adjustment jibs have screw threads on each end which can be adjusted to take up wear or tightness of the saddle on the bed, they also have adjustment screws set a short distance from each end as shown in the photo below left
The adjustment involves slackening off the tailstock side and tightening the headstock side making the jib move along until there is no play in the saddle. Note: the jibs are numbered 1 & 2 and should be replaced in same order.