Thursday 26th June

Work list:
Magnets!

Laurence popped out to get his hip replaced, so it was left to Geoff and Stephen to continue with magnet installation.

The previous assembly of a magnet 'unit', established the working thickness of the spacers (2mm). However, the cardboard was fixed with double-sided tape, which had wilted in the heat and weight of the magnet, and would have to be remade. With four to make, materials were prepared; 5-6mm plywood fixing plates with slotted holes, 2mm wood spacers, 20 x 3 x 40mm long steel strip keepers, and the magnets two 30 x 10mm units placed side-by-side.

The pieces were assembled with epoxy glue and we had lunch while they set.

We were occasionally able to use a Dremel router, but mainly had to resort to chain-drilled holes, a mallet and chisel, then finish with the hand-held router. The hole is 10mm deep in a piece of 1/2" chipboard. (Yes, we did break through once or twice, but no serious damage resulted.)

The yellow card spacers allow the magnet to be moved away from the track. The slots allow the magnets to be aligned with the track.

We fitted a couple quite quickly (we'd worked it all out before, you see) but as we reviewed the goods line, things got complicated. The goods-in magnet had to clear the shed point, pushing it halfway along the platform. The goods release (allowing the loco to run-around the newly arrived train) would have to go on the point. The two magnets were quite close together, which would restrict the length of goods trains being made-up. Only one answer - the goods assembly magnet would have to be the electromagnet. [We had purchased the Kadee electromagnet to experiment with, when we intended to build our own. We had decided to use it on the end of the platform, to allow assembled passenger trains to depart unhindered, but this new position made much more sense.]

Problem two was when we realised the points at the end of the platform worked together - crossover and both straight. With the magnet ON the goods point and the loco in the headshunt, the point couldn't be thrown to release it without launching stock on the point into the air. The solution was to change the point operation. After considering more extra wires, we realised that as the points were on different boards, they already had separate wiring, so it was a simple job to have the straight routes independent (keeping the crossover combined). A matter of seconds to achieve. Testing proved everything worked well.

Geoff will assemble the electromagnet ready for next week and read the installations. We also need one more magnet for the new goods area at the bridge.

Over our final cuppa, thoughts turned to the fiddle yard. Geoff has been against using aluminium angle for the running lines of the cassettes, but discussion of its other benefits - stock protection, alignment and jointing etc., led him to accept it was a good solution. We'll have to make one up as a trial.

Thursday 12th June

Worklist:

Assist Laurence to get his boat back into the Thames after some dry-yard work and then get it back to its mooring.
Lunch in Geoff's sun-drenched garden.
Work....... there was something we were doing.......it'll come to me........... Finish off the point rewiring!

It did take a while to get our brains back into work mode, but we made it. Geoff & Stephen took a board each and 1) rewired some existing connections and 2) incorporated the two extra wires to each board. The previous two-option arrangement (all-straight or all-crossed) was now replaced by four options:-

A quick running session to test it all? Nothing that simple...

With everything plugged in, all we had was a dead short. We tried isolating everything, to no effect. We eventually found a wire in the portable controller had opened up exposing bare wires. After a quick repair, normal service was restored. It all worked really well. The clunking definitely seemed less-fierce and using the four new routes seemed very natural. It was well worth doing.

Finishing off the magnets is next. After a quick review, we decided to omit all between-the-rails magnets and go for one electromagnet on the main platform and the rest as under-board home made units, as fitted the previous week.

Thursday 5th June

Work log:

Test alternative point motor
Work out how to split the 4-way point group
Legs

It was all points this week, with the aim of reducing the need for bigger, louder bangs when the H&M points are changed. First, Geoff had 'dug out' a bag of Conrad point motors that he'd bought on eBay. These were reproductions of Hoffman point motors and were intended for his 'other' layout, but never used.

The unit comprised a small motor driving a gear train onto a rack, producing the push-pull action. Internal contacts stopped the motor at each end, but didn't provide any frog-switching facility. An old 00 point on a piece of ply was fitted with the motor and variable power supply applied. It was quiet and the movement prototypical at lower voltages, but had a clunk, not unlike the H&M's, at higher levels. We decided it wasn't worth swapping over to them.

The cross-over is one of the track main features on the layout. At present, all four points 'fire' at the same time, changing the routes to 'all straight' or 'all crossed', which requires just two feeds. We have found that the points and the micro-switches supplying the frogs can be a little temperamental, which caused short-circuits. The immediate answer was to increase the voltage to the capacitor discharge unit, which would work, but would also increase the 'bang' supplied to the other single and twin points.

We had previously noted that it could be advantageous to rolling-stock movements, not to have all the points firing together, which would also reduce the load on the CD unit. We investigated the rail polarities and found two complete triangles of rail that would need splitting. The two 'frogs' at the centre of the crossover were already split horizontally and the board joint broke one side of the triangles, so only two further breaks were required. A couple of permanent jumpers were fitted and the assembly was successfully tested.

We then needed to supplement the two existing studs on the control panel, with two more and to re-route the existing wires to different point contacts. The new operation will be to switch each straight and cross-over separately. We fitted the new studs and extra wires into the loom before breaking for our final tea-break - it was a lovely day, after all.

PS - An interlude to the wiring occurred when we assembled a trestle leg we thought might make a decent board support. It came from Ikea, called Lerberg and cost £5 (each). We were pleasantly surprised by the material quality and even more so, by the rigidity. We originally thought it would need adapting to make it collapseable, but decided they could be 'nested'. It is too low, but a plywood extension notched to suit the allotted board will not be difficult to implement. So, off to Ikea for the other three!