Monday, 22 February 2010

Chassis Building Part 37465

I was determined that I would build an engine in 3mm. Surely it can't be that hard! I've talked before about building a chassis and I thought I had it cracked when I got to adding the wire pickups. I put in on the stretch of track that is supposed to be a layout and it stuttered along so I thought it would bed in. It didn't.

I decided it was time to invest in a rolling road. Gave the nice people at Finney and Smith some dosh and I have the rolling road (told her indoors it was a Valentines present from her to me....).

The rolling road is great but all it confirmed is that the chassis runs well in one direction but doesn't go at all in the other and if it does go, it uses twice as much current and the motor gets hot.

I think you can see the problem in the picture. The other side of the engine has the cranks perfectly horizontally in line. This side is definitely not 90 degrees, more like 85 degrees or less.

Now I have to break all the superglue that holds it together and see if I can correct it.

BTW I didn't have any track to hand so I held the rolling road together with brass tube and Royal Mail elastic bands - simplicity itself.

Sunday, 21 February 2010

Test Track on Chertonwell

Yesterday was Risex 2010 and we were exhibiting Chertonwell. It's a nice show with good mix of layouts, traders and demonstrations. Phil Parker popped in and commented on the test track we have on Chertonwell so I thought I would say how we did it. He has beaten me to an actual blog on the subject here.

On Chertonwell we run a lot of trains. Normally there will be 10 at any one time. Over a day that amounts to some 70 train hours of continuous running. As a result they can get dirty and need a good clean.

We decided that somewhere to clean engines would be good. What I did was take a piece of chipboard which was cut in two and had the corners cut off. I edged it so that items couldn't roll off - didn't stop us losing a spring yesteday which escaped whilst dismantling a loco. The board is hinged down the middle, In the picture you can see the timber in the centre of the board with hinges on top so it folds flat.

I glued settrack to it so I didn't have to fight the springing of flexitrack and the wires go to two banana sockets. Just over on the right you can see the flexible wiring to allow the board to close. The board bolts to the layout when in use by the coach bolt whose wing nut can be seen at the rear. The layout has a separate controller built in, the controls being to the left of the photo.

We literally bolt in on and plug in two banana connectors and it's ready to go. The only addition since first use is a resisitor that allow the current flow to the loco to be measured. Very useful for seeing whether any current is actually flowing.

It's a really useful feature of the layout and we would be lost without it.

Saturday, 13 February 2010

Wiring Woes

After the last (and first) outing of Mospick Halt I decided I should put a power LED visible somewhere along with the short LED. The controller has a short LED on it so all I needed to do was unsolder it and run wires up to the control panel area.

The power LED was equally easy, find an LED, use good old Ohms Law to determine a suitable resistor, wire them to the power feed, a quick test and put the layout away.

The completion of the next engine meant a quick run was in order. Unfortunately what I discovered was the power LED flashes when the engine is running in one direction and is completely off when the engine runs in the other direction. Not only does the LED flash but the engine slows down gently instead of suddenly when the controller was turned off. I had done something seriously wrong.

In the end it was quite simple. I had wired one side of the LED to the power bus on the layout but the other side got wired to one of the track output wires. I had used confusing terminology under the layout. All the wires go to tag strips that are labeled but my choice of names was not good!

I took the opportunity to separate out the lights on the layout onto their own switch. Previously they were on all the time but they will be hardly noticed at exhibitions so it made sense to be able to turn them off and save carbon emissions somewhere.

Monday, 1 February 2010

Joan

The last exhibition showed the need for a good 3rd engine. I had the Chivers Finelines RC17 Welshpool & Llanfair Joan kit sat in a box, so out it came.

The kit was designed to go on a Minitrix chassis but I had bought a couple of the Dapol 2-6-2 tanks when they were cheap on the OO9 Society Second Hand stall so these were an obvious choice for conversion to an 0-6-2.

Removing the body and pony trucks showed that I just needed to lift the coils and capacitors and make a larger hole in the footplate and it would be a perfect fit. I needed to remove a locating lug so I sawed that off and promptly sawed through one of the wires which are ever so tiny and delicate. A repair by my good friend Bob had it running again in no time.

The body was cleaned up and glued with superglue gel. Working with whitemetal is so easy. No fiddling with soldering irons unless you want to and it is easy to file and to fill. The whole kit took only a couple of hours time to put together.

One nice touch was the coupling hook on the rear which I was able to superglue into the NRMA standard socket on the trailing pony truck. It provides the necessary movement on tight bends and was easier to do than expected.

I've made one mistake in not putting the fixing nuts in place early on but I reckon I can still do that. The picture shows the completed body with a few gaps to fill with putty. After that it's a case of clean it up and take it into the garden and spray it.

Hopefully this will all be done in time for Abingdon show in early March.