It’s been great to be back in the workshop and actually doing a bit of model engineering and using eyes, fingers and brain to design and make things without the aid of a computer and a computer-driven device. That digital card cutter and its associated computer programs have taken a lot of learning time and I’ve missed being in the workshop environment.

I knew I got pleasure out of designing, fabricating and machining, but building the two chassis for those computer-produced brake van bodies has reinforced that belief.

The two (may become three!) Great Central six wheel brake vans, now each have a working chassis; a couple of chassis that worked well first time, (well, with one minor hi-cup!). The “may become three” was added because sentimentality may have me make a chassis for the hand-produced body I made so many years ago but rejected when my attempt at making a six-wheel Cleminson chassis failed. Such a complicated chassis would be a non-sense anyway in this particular application.

I’ve written on here before that I have believed in sprung axleboxes for locos for many years and I use a system first devised by Alex Jackson and Sid Stubbs in the 1940s. Their wagon chassis used what I think is a unique system combining springing and ‘wobbly’ axles, quite complex and demanding of high skill levels. I never attempted to copy this but since Bill Bedford introduced his etched ‘W’ irons with sprung bearings, that, or a derivative of it, is what I have used. I tried the Masokits sprung chassis and would recommend them, but Bill’s are simpler to make. However the Masokits design produces a chassis of correct wheelbase and with truly parallel axles every time; Bill’s units need fairly high skill levels to achieve that parallelism.

The secret of the Masokits units is what I choose to call “the central spine”. I’ve pinched that idea (sorry Mike if you read this) and linked it to Bill’s etches. Indeed I drew my own drawings and had some chemical etchings done, this in an attempt to overcome some niggling changes introduced by Bill or his successor for his etched items. No, sorry I shall not be marketing my etchings!

So, these GCR brakes have a central spine chasses with the outer axles carried in B-B type sprung ‘W’irons and with a very sloppy centre axle carried in inside bearings. This sloppy axle can rise & fall through approximately 0.030” and has side-float of about 0.020”. That “minor hic-up” mentioned above, was in my maths used to mark-out the inside bearing carrier in-the-flat (it’s a folded, square ‘ U’) - I managed to fold and achieve parallelism, but the axle holes were too high by about 0.050” and, when on the track, although it looked OK when stopped, when it moved, the outer wheels rolled nicely but the centre wheels stayed quite still.

After several “oh dear me-s” or words that mean that, I made a new bearing carrier with corrected dimensions and carried out my “fling test”. I’ve described this before on here but for any new readers it means I “fling” the vehicle along a section of my S4 layout ‘Bowton’s Yard; this section starts with a B6 Turn-out, through a second one and then a B6 double slip, all on a curve of around 6’. “Fling,” means exactly that! -pushed hard so that the vehicle’s momentum causes a scale speed of the order of sixty miles an hour. At least four trips in each direction without derailment is the acceptable result. Rarely is the vehicles first test an acceptable one; they normally need to go back for a bit of tweaking. These two were good first time, so I must have got something right.

So exhilarated at being back to model engineering, I’ve gone on about these two brake-vans for too long. I should first have shown you some pics of custom window frames, doors etc produced by that card cutter, particularly the windows for a Model Railway Scenery’s 1930s factory that now sits comfortably on Bowton’s Yard; next time perhaps; meanwhile here’s a few pics of the brake-van progress.

The van on the left has had the scribing emphasised by being rubbed with pencil lead dust and includes the roof insert. The right hand one has the central spring/axlebox unit in place but the outer axles show the outer ends of the waisted, pin-point bearings ready to be covered by modified MJT white-metal, axlebox/spring units as per the left hand one. The roof insert is missing from the right hand view.

Perhaps an explanation of "roof insert":- In order to allow access to the verandas, I want to be able to easily remove the roof. Accordingly these inserts were made as a fairly tight fit inside the van body. The roof itself will be carried by these, so allowing the roof to be plugged out as it were.

Front & side view of these inserts. Worth noting that they are a pair, well colour coded and numbered to ensure no muddles, but finally welded as one with a central spacer, filed and adjusted to make the whole unit a good fit inside its dedicated van. The black shading in the top corners will be behind the glazed van windows - it'too dark in there to be able to see inside!?!

Here we see one insert in position and viewed from above, while the second shot shows some detail of the removable underframe.

For the good-sighted and axlebox knowledgable, I am aware that the central boxes differ to the outer ones!. This was originally an oversight

but accepted on the grounds that this did happen in real life, and with my operating period being late 1940s, these brakevans from the 1890s would have seen a good amount of repair and change. Any way it's my railway and I'll do what I want - so there!

Dave