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Latest News

Current news items are listed below. If the Acrobat icon is shown, then click on the icon to read the attachment. If an image is shown, you can click it for a full size image. You can find old news items in the News Archive.

Bogie Suspension System
12/04/2021
  Highslide JS
  We are now starting to procure parts for the bogie suspension system. The bogie differs from the the other wheels on the locomotive in that the springs do not bear directly on the axleboxes. The main spring is an inverted leaf spring, 1 fitted on each side of the bogie frame in a spring cradle running alongside the frames of the bogie. The spring cradle is in effect a compensation beam in that the movement of one axle is partly transmitted to the other axle as well as to the spring. The central buckle of the leaf spring is attached to the central bogie stretcher whereas the ends of the leaf spring sit in these Spring Cradle Brackets - fitted to the Spring Cradle - made for us by Alpenbury Precision Engineering Ltd in Rotherham. They've also made the pins that will be used to secure the brackets into the cradle - these will be welded into the cradle.
   
Bogie Pivot Centre Slide
30/03/2021
  Highslide JS
  We're back in Sheffield again this week so its time to catch up with what has been going on. The bogie pivot centre slide is almost through machining. In the photo, it is sitting upside down. The pivot, which is bolted to the pivot stretcher on the main frames engages with a bush in the hole where the paper work has been pushed into. The centre slide sits on the flat faces which are lubricated by oil in the diagonal grooves. It can move to the left and right under the control of powerful side control springs. As you can see, 2 off 7/8" British Standard Whitworth threads need to be formed which will be used for screws to retain the bush. Unfortunately the tap to create the thread has broken and a new one is required. There's not much call for Whitworth threads these days!
   
Bogie Axlebox Guides
30/03/2021
  Highslide JS
  8 bogie axle guides with first phase machining complete waiting for inspection. If you look closely, you will note that we have 4 off item 1, 2 off item 2 and 2 off item 3. Item1 are the 4 guides that sit at the outer ends of the bogie frame. The inner ones have to accommodate the bogie spring cradle (or compensation beam) that connects the tops of the axleboxes on each sides of the bogie frame on the outside. The 2 bolts on the tops of the axlebox guides have to have countersunk heads to avoid fouling spring cradle. Once the bogie frame has been assembled and aligned we will final machine the axlebox face of the guide.
   
Frame Measuring
30/03/2021
  Highslide JS
  Phil Yates, on our Engineering Committee, from the Advanced Manufacturing Research Centre (AMRC) has arranged the loan of a laser measuring device. We spent the day measuring the frames; in particular carefully noting the dimensions of the hornguides post machining. Here Phil and Geoff (just visible) are doing a survey) of the cylinder mounting area.
   
BR1F Tender Frames Modelling (2)
22/03/2021
  Highslide JS
  James has been pressing on with the modelling of the tender frames. The frames are outside of the wheels so that the triangular brake hanger brackets need to be inside of the frames. The 6 spring pivots and brackets can be seen on the outside of the frames. At the front of the tender frame (left) is a rubbing block, very similar to one which we will be fitting to the hind beam of the engine frames.