After a few weeks, with a fair bit of frustration, there's been a small amount of progress. One job was to model the axlebox springs which would have to be removable. So I re-designed the hornguides with lugs to accept the springs, and designed the springs to fit them. I opted to use 14BA screws to hold the springs in plce and that was the first hold-up. I thought I had some 14BA taps and screws, but couldn't find them, so it was on to the Internet and order some. They came quite quickly but I had ordered screws which were a bit too short, so I re-ordered a longer version, but they got held up since the supplier was changing his courier and that incurred a few days delay. But we got the act together by the start of this week. Here's the centre hornguide with its springs and screws. Apologies for shallow depth of focus. This shows the lug a bit better being fitted on the front of the existing model spring mount and I've also taken the opportunity to represent the spring mounting brackets on the frame. The springs fixed with the 14BA coutersunk screws. The countersink on the spring is drawn in 3D and printed. The screws will be fitted through the spokes of the wheels The rear axle on the locomotive has coil springs, so I drew some up and printed them. They actually work as springs although I don't know how well they might survive in service. The 14BA screws here are on the underside, so fitted from underneath. Here's the frame assembled so far with all the springs fitted. The resin taps quite well with the 14BA tap and the screws screw up quite tightly without stripping the threads. I was a bit worried that the 14BA thread would be too fine and that I might have to resort to coarser threads, but so far so good. I've also probably got an answer to a bit more frame staying between the rear two axles. I've drawn up a firebox to fit in the area and that will supply good staying. I haven't printed one yet. I'm waiting to get the gearbox first so that I can tailor the print to suit. An order has gone out to ABC for a gearbox and motor so work will probably go on the back burner until the gearbox appears. Jim.