Sunday, February 12, 2017

How I converted a Dapol A1X Terrier loco to battery radio control

After admiring the sleek lines and refined detail of the Terrier, the first task was to separate the body from the chassis.

The four screws securing the body were removed, two at the front and to at the rear .......

 The chassis was then eased out from the body.

The flickering LEDs were removed from behind the firebox door.

 The mounting plates were removed from alongside the motor.

The decoder blanking plate was removed from the the DCC connector.

The DCC connector ........

... was then unscrewed........

I then considered where I could place the charge socket, indicator LED. The best place seemed to be the bunker. Rather than routing the wiring through the cab, I decided to burrow underneath it.

A slot, 35mm x 10mm was marked out extending from the cut-out for the motor to the rear, reaching just inside the base of the bunker.

 After removing the steps, the slot was cut out with a carborundum slitting disk in a mini drill.

 Space was needed in the bunker for a miniature two-way slide switch, a 2.5mm DC socket an LED indicator LED and a three-pin JST plug.

A 39mm x `4mm rectangle of 1.5mm thick black plasticard was cut to and holes drilled and cut to accommodate the components - 7.5mm diameter for the charge socket, 6mm dia for the LED indicator, 11mm x 5.5mm for the slide switch and 3mm dia for the leads to the 3-pin JST plug.

 The slide switch, LED indicator and charge socket were mounted into their holes. 3.5mm was trimmed off each of the contacts on the DC socket and a 280 ohm resistor was soldered from the negative lead on the indicator LED to the middle (-ve) contact of the DC socket.

Two pieces of 14mm x 14mm plasticard were glued to the ends of the mounting plate and a 5mm wide strip glued between them.

When the solvent adhesive had hardened, the components were wired-up to a length of 8 way ribbon cable....

The cable was then threaded into the slot between the bunker and the motor compartment and the assembly was then eased into the bunker. There was no need to fix it into place as it was a very tight push-fit.

Meanwhile four 10440 320 mAh (AAA sized) li-ion batteries were acquired from Norbert at Ecolux. These were made up by him into two solder-tagged parallel packs of two batteries.

 The tags were shortened and tinned with solder .........

  ...... before being connected to a 2S li-ion battery protection board.

The ribbon cable was then wired up to the protection board and a Deltang Rx60c receiver controller ......


...... which in turn was connected via a 2 pin micro JST connector to the motor. The LED was connected to output Pad 1 on the Rx60, which provides a forward direction headlight and also mirrors the flashes of the receiver's LED when the receiver is not in normal use. Thus the indicator LED can show when the receiver is in bind mode (rapid flashing) or when the batteries have become depleted (the LED gives five flashes, pauses, five flashes, etc). When in normal operation the LED glows when the loco is supposed to be moving forward and extinguishes when it is supposed to be travelling in reverse. When the receiver loses or is looking for the transmitter signal the LED flashes once a second.


The loco was then reassembled. The battery packs were squeezed into the side tanks and wedged in place with 10mm squares of 2mm thick plasticard to prevent them from bearing on the flanges of the centre driving wheels. The receiver was placed inside the smokebo, making sure the wiring avoided the flywheel (there is just space!).

The loco was then tested and enjoyed.

This was a very fiddly conversion, made more difficult because of the delicate detailed features on the loco body. Some of these were removed during the conversion process and then reinstated when the conversion was completed.

The motor and loco mechanism is very smooth and so is well suited to battery power and radio control - once the problems of finding room for the batteries and the various circuitry and components had been solved.

This conversion is not for those of a nervous disposition or a faint heart. On reflection, I would have used even finer wiring than that provided by the ribbon cable. It might be possible to position the Rx60 behind the motor to leave space for a soundcard inside the smokebox. There is just room for the Rx in this space but it would have been difficult to ensure that the antenna did not make contact with the metal casting, thereby interfering with its acuity. I did consider reconnecting the firebox LEDs by connecting them to one of the output pads on the Rx, thus putting them under the control of the transmitter (eg Channel 5, bind button). However, this would have entailed even more wiring in the confined space available and so I chickened out.



Tuesday, December 20, 2016

How I made and installed some picket fencing on my railway

I have reached that stage in the construction of my railway where I am turning more of my attention to adding finer details. The main station (Beeston Market) has undergone a few changes since it was first built, with sidings being added and the length of the station being extended to include access to the storage roads in the garage (see Progress Report 59). This created a forecourt area for the station which has remained largely undeveloped. What I felt was needed initially was some sort of separation between the railway and the outside world - ie some fencing.
I decided to invest in some fencing packs from North Pilton Works. These seemed to me to be the most cost effective way of getting long runs of picket fencing and so I very shortly took delivery of four packs - a level crossing pack (see How I made a Level Crossing), a fencing pack and two gate packs.


The gate pack was opened first..........

....... to reveal a set of laser-cut components .........

..... and a set of instructions.

The first job was to measure up the site to work out the length of fencing I'd require. To fit the gate for the station yard in the right place, I worked out that I needed to shorten one of the fence panels from 117mm to 70mm. One panel was duly shortened, making sure I left the locating lugs on both ends.

Next, I started making-up a series of posts. These are constructed from three components; a plain outer piece, an outer piece with a peg at the base and a notched inner piece.

These were glued together using exterior PVA and short lengths of dowel to help align the pieces.

 The fence panel was then glued to the post using the slots in the post.

The next post needed to be double-sided to support a panel on each side. This was constructed from three sections, the centre section including two sets of notches.



 The post was then glued together and inserted between the existing short length of fence and a full length of fencing. Battens were then applied behind the panels.

The bases for the posts were then glued on. 

... and the run of fencing was left to let the glue dry. Note that as the right hand post will be a gate post, it has a raised edge to act as a gate-stop.

This was constructed from three pieces as previously - one of the outer sections containing the gate-stop.

The next run of fencing would require a 90 degree bend and so a corner post was put together from three sections; one of the outside pieces including rectangular holes to receive the tabs on the fence panel at right angles to the normal run of the fence.

The remaining sections of fence panel and posts were constructed as above.

 The gate for the station yard was constructed from a fence panel with a backing piece comprising framing battens and a diagonal. The holes are to take the screws for hinges (supplied in the kit).

I decided at this point to make myself another gate using a spare fence panel. The tabs were removed from the end of the panel...

.... and two verticals were cut from an offcut of fencing panel.

The verticals were glued on to the fence panel and horizontal battens glued between them. A diagonal batten was then glued between the two horizontal battens.

The completed fence panels and gates were then given a couple of coats of resinous wood hardener as I wanted to ensure they would survive the damp environment in my shady back garden.

They were then given a couple of thin coats of exterior housepaint (light cream).

The bases were then given a coat of greeny-grey acrylic to represent concrete.

and 1.5mm diameter brass rods were inserted into holes drilled into the bases to act as locating pegs when the fencing panels will be installed.

Once the paint had dried, the hinges were then screwed to the gates and gateposts.

I decided to construct my own latches for the gates. These were made by cutting a 5mm strip of 1mm brass sheet and soldering a short length of 2mm diameter brass tube to the end.

 The end with the tube was then snipped off and the solder filed smooth.

A short piece of 1.5mm diameter rod was inserted into the tube, bent at 90 degrees and snipped off to form the bolt for the latch.

 Latch plates were then made in a similar way to receive the bolts.

 The latches were then superglued to the gates and painted with primer and black acrylic.

 The lengths of pre-assembled fencing panel were then taken out into the garden and fitted into place, holes being drilled in the baseboard to take the brass pegs on the base of each post.

 At the moment, the fencing has been fitted temporarily. I need to do some landscaping to build up the verges and curbs and the road surface. Some of the bases of the posts are therefore 'floating'. (Note one of the galvanised nail heads in the foreground. These will act as keys to help fix the concrete screed to the baseboard).

Eventually, the bases of the posts will be buried in the ground and will hardly be visible.

I could have left the bases off completely and will do so when I fit fencing at subsequent locations. I did try removing them, but the PVA had bonded far more strongly than I expected.

I will add more information and pictures to the foot of this blog-post, when I have finished the landscaping (weather permitting).

In the meantime, the fencing seems to be able to bear quite close scrutiny.

Though I am going to have to paint those hinges!!

 The packs of fencing and gates from North Pilton Works seem to present good value for money at less than a pound (GBP) per panel. Having tried to make my own picket fencing from wood and from plastic and discovered it's not easy to get the spacing consistent or vertical, these panels give a much better finish than I know I could achieve. I still have more than enough fencing left to complete the fencing at the other end of the station - another job for the never-ending jobs-list.

I will keep you posted as to developments when I finish off the landscaping.