Having fitted the bolts to 5 sets of horn blocks so far the final 14 bolts are seen here during manufacture. The two on the left have their shanks rough turned and their screw threads cut while their heads have yet to be domed. The remainder have already been done and now await their shanks being turned to finished sizes with the required tolerance to suit their individual holes in the frames.
Although we have access to the majority of the original drawings we need for the overhaul, many railway drawings were produced of assemblies. Where specific parts are needed, separate detail drawings of the particular items have to be produced either to ensure clarity in the workshop or to pass to our supplier when parts have to be bought in. An example are the two expansion links which have to be replaced for which the drawing shown here has been produced. This shows the finished product but needs to have some machining allowances added when we have finalised the production process to be used and can place an order.
Work has also started on producing the studs that are required to be fitted in the underside of each horn block and used to secure the horn stays when fitted. These horn stays which are the next items to be machined and fitted, straddle the gaps between each pair of horn blocks to retain the axleboxes in the frames. This will become clearer when we have a photo to show you.
First published on the WSRA 4561 restoration blog.