Problems

Hi folks,

No post for yesterday, I was working on a customer order - hooray! Some small jobs have been creeping onto the books so things look OK for this month.

My Father's PC has died and despite all my efforts it would appear that the motherboard has given up the ghost. This is causing him some grief because, since my mother died 18 months ago, his PC has been a bit of a lifeline to the outside world. It seems that the hard drive data is intact so we should be able to get him back up and running again.

I went to price up a job to fit a replacement shower this evening, it would have been a straightforward job since it's an instantaneous electric one and the element had burnt out. However, on actually viewing the site I became far more concerned with the fact that there is an obvious leak, either in the water feed or the waste pipe system. The ceiling of the kitchen below has become so water logged that a section 4 feet by 4 feet in in danger of falling down!

I'll be on site tomorrow so we'll see how we get on.

The model railway has hit it's first major hold up. I've spent a lot of this week wiring up the electrics to the control box. In the images below you can see the wiring loom for the isolating sections and the point motor switches. Note that as yet there are no electronics for the controller installed. This is because I have 4 different prototype designs in the testing stage and I don't know which one will be fitted yet. In the meantime I am just using my loco testing controller for some running tests.

Once the box was wired up I began testing the track for correct operation. In the lower photo at the top you can see the small 6 wheel diesel shunter used for the tests. I use this because of it's short wheelbase which is likely to show up any losses of contact over points and suchlike.

On testing I found that all the isolating sections worked as they should and all the point motors were firing as they should, but I was horrified to discover that only 4 out of the 7 sets of points were changing correctly. The nature of the problem soon became evident. The points are thrown by simple solenoid switches, one can be seen in the image below.

Similar ones to these are manufactured by Hornby, Peco and these known as Seeps.

The travel required to throw the N Gauge points I am using is only 2mm, but because of the thickness of the baseboard I chose to use for the station, the drive pin is flexing such that the motors maximum travel of about 10mm is not enough to throw the point!

Having examined the motors carefully some have a fraction more play in the solenoids than others. Only by a factor of about 1/2mm but when this is multiplied over the 25mm of the drive pin it is enough to fail to throw the points.

There are a number of possible solutions. I could dump the entire base boards and start over using 6mm MDF throughout, not a palatable idea. I could revise the mechanical linkage, possibly for a crank based system which would allow the motors more travel and more torque, I am still toying with this one. Or I could route out recesses for the 3 point motors that are suffering, thus reducing the length of the drive pin and eliminating the flexing. At the moment, the last is the most favourable but also the most messy to perform with all the under board clutter.

Mounting the motors above the baseboard and 'hiding' them would have been an option but the layout planning has not allowed for this. If anyone out there has been following this blog and is thinking of modelling in N Gauge, don't use a baseboard thicker than about 9mm if you are mounting the motors beneath the board.

The next railway post will include my resolution to this problem, and a discussion of the electronic systems.

Model Railway

Well, my wife and I scoured the house to find a place for a model railway. The loft was no good due to the head room (only 4ft), so my dreams of a huge continuous run with express trains dashing around were out.

After much scratching of heads we finally decided that the only safe, unused and covered area was in the front porch! There are two shelves about 30 cms wide by 1.6 meters long joined at the corner. Not very inspiring but beggars can't be choosers, so I set to work planning.

The 'normal' gauges and scales were out because of the restricted space, so no 'OO' or 'HO' scale. That left me with three possible options. 'N' Gauge, 2mm Finescale, 3mm Finescale. I soon abandoned the finescale options since the thought of hand building yards of track was too depressing. 'N' Gauge it was then.

At a scale of 1:148 or roughly 2mm model size to one foot real size it would fit with enough operating interest. I decided to plump for the ever popular late 1940's to late 1960's covering British Rail's hayday. With some licence this would mean being able to run steam and diesel locomotives, along with a large range of rolling stock.

As to the design, I went for a 'Branch Line Terminous' station with a viaduct corner section and a non-scenic 'Fiddle' or Marshalling yard at the other end.

Here's the basic station layout on it's chipboard base, the chipboard was a mistake as shall be seen in a later post, but the basic elements are shown here. The simple track plan has been drawn out and the semi-constructed buildings are evident. Some slight re-arrangement took place before the final plan was arrived at.

Here's the fiddle yard board with the track design drawn up, again the MDF shelf that I used as the baseboard was a mistake, but it's done now.

The corner section built from 6mm MDF, if I ever do another layout this is what I will use for the baseboard material. Since the viaduct was to be curved, no kits were available, therefore it had to be 'scratchbuilt'. The first three pillars (made of cardboard) can be seen on the bed waiting for fitment.

The five pillars in place, the lower portions have been dressed with 'brick papers' and the arches are under construction, once all the glue had set these pillars became extremely strong.

The pillars have been dressed, the abutments added, and the archways installed. The parapet and approach walls will be added after the base has been built up into mountains. The back frame has also been added.

That's enough for this post, watch this space to see how progress goes.