14 January 2015.
- Text related to using wire handrails and etched ladders added to first paragraph.
- Comment related to 3D printed counterweight levers on signals removed. These are no longer printed on signals.
- Extra information about the use of glues added.
- Painting and lighting of signals sections amended.
- Instructions on how to cut the detail parts away from the sprues.
- Extra instructions when drilling the counterweight lever arm to stop the arm from bending and possibly breaking.
- Replaced photo of bracket signal rodding order.
- Added some references to HO Fine Detail signals, ladders and safety handrails, wire and drill sizes for 7mm Scale.
It is advised that the following construction details are followed particularly in relation to the installation of the various wire operating rods.
The bracket signals are of the type that have bellcranks not wheels to transmit the action to the signal arm and of course this is usually achieved with wire not rods. Wire though is not really possible in HO scale due to the lack of weight of the counterweight to hold the wire taut.
These instructions are based around a bracket signal as this is the most complicated signal. The same processes are to be followed for the simpler signals.
If you wish to have finer handrails and ladder they may be cut away with transistor cutters after the existing printed handrails have been used as a guide to bend up some wire handrails. The post and the landings could be drilled at the printed attachment points to accept the wire. For HO use some of the 0.15" (0.032" for 7mm Scale) phosphor bronze wire listed below. Etched ladders are available from several sources.
- 2-56 x 1/2” black acetal plastic or metal screws available from Kadee are required for the operating mechanism adjusting screws, alternatively 8 BA x ½” screws can be used. These screws (or some other equivalent) must be used as a small head is required to clear the adjacent screw(s) on multiple arm signals.
- #4 x 6mm self-tapping screw available from Jaycar (HP0550) for attaching the main crank to the mechanism mounting.
- 3mm M3 washers available from Jaycar (HP0431) or 1/8” similar washers to hold the cranks on.
- HO - The signal operating rods are 0.015” Tichy Train Group Phosphor Bronze wire (Part No. #1102 - 12 x 200mm lengths in a pack).
- 7mm Scale - The signal operating rods for are 0.032” Tichy Train Group Phosphor Bronze wire (Part No. #1105 - 12 x 200mm lengths in a pack).
- Below baseboard operating rods are 0.032” Tichy Train Group Phosphor Bronze wire (Part No. #1105 – 12 x 200mm lengths in a pack).
- 0.4mm or a No. 78 drill bit for wire operating rod holes in the parts on the Fine Ultra Details sprue.
- HO and 7mm Scale - 0.45mm or No.77 for White Strong Flexible main operating crank.
- HO - 1mm or alternatively a No. 60 or 61 drill bit is required to clean out HO signal arm pivot hole on post and to drill the hole in the bottom of the main below baseboard crank for the operating rod to the servo or other mechanism (relay, push rod, bowden cable or other arrangement including manual).
- 2mm or 5/64” drill bit used to clear screw holes in main operating mechanism of remaining nylon powder from printing process.
- A pair of transistor nippers (side cutters).
- A selection of small and very small paint brushes are required, e.g. 1, 0, 00 and 000.
- Various paints listed below
Cleaning the White Strong and Flexible Parts
Cleaning the Frosted Ultra Detail Parts
The signal lenses can be made by using Krystal Clear or probably PVA glue and wiping into the lens area with a toothpick until it covers the lens hole . After drying clear the lenses can be coloured using Tamiya X-27 Clear Red and X-23 Clear Blue. The 'green' lens of a signal was actually blue glass as the yellow light from the kerosene lamp when viewed through the blue lens produced green.
If the signal is to be lit the Tamiya X25 Green Clear is best used as the LED is not yellow enough to show through the blue clear as green.
If the signal is to be lit then the areas of the post around the signal lamp need to be painted black then painted white as required for the post. This is to stop light transmission through the post from the LED (see photo of effect).
Some light will still be reflected back from the signal lens and this might be reduced by using matt clear on the rear of the lens (see photo).
|Lamps showing in 'daylight' - 1K Ohm resistor|
The signals have been designed to be lit if required.
The signal lamps on the posts have been printed without lamp tops which can be found on the signal detail parts sprue.
it is best to buy the SMD LEDs pre-wired (0.8mm Golden White LED with 150mm / 6 inch leads), they can be bought without wires but
they are so small that soldering very fine wire is difficult.
The lamps on the signals have a slot in front and back. The rear is to allow the wires to come out and the front is a slot as the minimum wall thicknesses make it difficult to have a lens or hole.
The 0.8mm SMD LED will be a slight push fit into the hole in the top of the lamp and the square LED sticking out of the front of the tiny circuit board will fit into the slot.
A small circuit board can be made from a printed circuit board (PCB) sleeper or with a piece of PCB cut to size (4mm x 15mm). The copper on the PCB is cut down the middle of its length with a fine stone in a hand motor tool (Dremel, etc.) and then one side of the copper is cut at the half way point. A 1K Ohm resistor is soldered across the half way gap, this is the +ve side of the circuit. The other copper strip is the -ve side of the circuit.
The wires on the male plug are soldered across the two holes rather than into the holes, this is needed from clearance from the main operating crank of the signal (see photo).
Please note that the plug and socket doesn't have to be on the circuit board or even used for that matter. This method is presented in case the modeller wants to disconnect the wiring from the signal.
Once it has been confirmed that the LEDs work then the wires can be painted over or even smoothed over with a filler. It has been found that Selleys Spakfilla can be applied and once dried the signal can be flexed without it falling off. Spakfilla is an interesting material, it has no real weight and must be pushed onto the surface then carefully smoothed with a metal spatula or similar tool.
The Main Body - Signal Post, Mounting Baseplate and Operating Mechanism
The 7mm Scale signals have the finial printed as part of the post.
Bellcrank and Counterweight Brackets on the Post(s)
Again for HO use a 0.45mm or No. 77 (0.8mm for 7mm Scale) to drill through the small bellcrank brackets and into the post and beam on a bracket signal. Repeat for the counterweight brackets.
Place a rectangular cross section toothpick or piece of scale timber into the slot of the brackets for the counter weight lever and the small bellcranks as a drilling support then drill for HO 0.45 mm or No.77 (0.8mm for 7mm Scale). There is a very small dimple in the brackets where the hole is to be drilled, take care when drilling these holes and keep the hole at right angles to the post in both the vertical and horizontal planes.
Note that the drill bit size for the White Strong and Flexible (WSF) is one size larger than for the holes in the Fine Ultra Detail (FUD) parts. The reason for this is that the WSF tends to stretch when drilled and then shrink back.
The arm on the bracket main post is as normal with just the two rods.
Rod 1 from signal arm to counterweight lever
Temporarily fit the signal arm into the pivot on the post and the counterweight lever into the pivot on the bottom end of the small signal dolly. With the signal arm and the counterweight lever in the middle of their potential travel, measure the distance from the hole in the signal arm to the outer hole near the counterweight on the counterweight lever and record it. For HO cut and bend a piece of 0.015” (0.032" for 7mm Scale) wire rod making the bent part on each end at least 2mm long (the 90 degree bends on both ends go the same way). Fit the rod into the signal arm from the rear leaving about 2mm sticking out the front of the arm, this will be trimmed later when the signal is operating satisfactorily. Now slide the rod into the hole nearest to the counterweight on the counterweight lever, slide the signal arm pivot rod into the mounting hole on the post and at the same time swing the counterweight lever into the pivot on the small dolly post. Now for HO using a short piece of 0.015” (0.032" for 7mm Scale) wire rod with a right angle bend of 1-2mm on its outer end (to protect your finger tip), push the wire rod through the outer pivot hole, through the counterweight lever and then into the hole in the post. Once again leave 2mm sticking out for later trimming.
Rod 2 from End of Counterweight lever to Outer Bellcrank
Temporarily fit the outer bellcrank into the pivot on the bracket beam below the small signal dolly post with another piece of wire rod (bent on outer end to protect your finger tip). Ensure that the counterweight lever and the bell crank are in the middle of their potential travel. Measure from the hole in the outer end of the counterweight lever to the hole in the outer end of the bellcrank and record it. For HO bend a piece of 0.015” (0.032" for 7mm Scale) wire rod to this length making one bent end piece go one way and the other bent end piece go the other way (a right angle Z shape).
Rod 3 from Outer Bellcrank to Bellcrank on Main Post
For HO, now the 0.015” ((0.032" for 7mm Scale)) wire rod from the outer bellcrank to the bellcrank on the main post must be made. Temporarily fit the bellcrank to the pivot on the main post using another piece of wire rod bent on the end to protect your fingertip. With both bellcranks in the middle of their travel, measure from the top hole in the bellcrank on the main post to the outer bellcrank lower hole and record it. Make a wire rod to this length with the right angle bent ends being the same way and at least 2mm long.
Remove the main post bellcrank pivot rod and attach the wire rod that runs between the two bellcranks from the top hole on the main post bellcrank to the bottom hole on the outer bellcrank.
With the previously made Z shaped wire rod held horizontal, slip one end into the hole in the outer end of the counterweight lever, remove the pivot rod from the bellcrank pivot, slide the bellcrank onto the wire rod, swing it down to the bellcrank pivot and push the wire pivot rod back through the pivot bracket and into the post.
Rod 4 from Main Post Bellcrank to the Main Operating Crank Mechanism
Now, measure, cut, bend and attach the wire rod from the main post bellcrank lower hole (insert wire rod from the rear of the bellcrank) to the operating crank below the baseboard. Leave the lower end of this wire rod long enough to go past the under baseboard crank and do not bend or fit it to the crank at this stage. Swing the main post bellcrank into position in the main post pivot and fit the pivot pin into the pivot and the post.
If all has gone well each wire rod will be held in place by other wire rods and parts of the signal itself.
If you gently pull and push the long operating rod from near the operating crank below, the small dolly post signal arm should work.
This long rod may want to flex away from the post and not fully transmit the movement. I have found that a small ‘U’ shaped wire staple of the 0.015” wire can be inserted into 0.4mm holes drilled into the post just below the horizontal ladder supports part way up the post to minimise this flexing (see photo below). Make one side of the ‘U’ longer and insert this into a single hole as it is easier.
If the arm doesn’t move properly then you have to look at each wire rod that you have made and adjust accordingly.
Rods 5 and 6
The rodding for the signal arm on the main post can now be done similarly to fitting the small dolly signal arm operating rod to the counterweight lever above and then the operating rod down to the main crank can be fitted. Slide the rod behind Rod 3 which will trap it in place.
Note that all bent rod ends face to the front of the signal except for the Z shaped rod that has the upper bend facing to the rear.
Unfortunately I can’t give any help on the length of the various rods as the adjustments involved for each rod length can be quite small. Persevere and it should work.
I found that using a Keiran Ryan Models etched brass hand rail bending jig beneficial.
Final Fitting and Adjustment of Signal Operation
If the signal arms work nicely then the rear light shield can be glued onto each signal arm shaft where it exits the signal post pivot. This will keep the signal arm in place. Care needs to be taken here so that the glue doesn’t go through the hole in the light shield pivot boss into the post pivot hole and glue the arm to the post. It is suggested that a thick glue or contact cement be used and only on the rear of the light shield pivot boss, DO NOT USE SUPER GLUE (ACC).
At this point the excess signal arm shaft can be trimmed with a pair of transistor nippers.
Now the long vertical operating rod down to the main operating crank can be bent and fitted as follows:
Fit the main crank to the mounting with a #2 x 6mm self-tapping screw and a 3mm or 1/8” washer as shown in the photo below.
Attaching the last Detail Parts
Finally, glue the previously painted cast iron support to the post and the underside of the bracket beams. If Super Glue (ACC) is used then it may require several applications as the glue will be absorbed into the surface. Alternatively a Super Glue accelerator may be used, apply the glue then immediately apply the accelerator to set the glue before it is absorbed.
Glue the finial to the top of the post.
Glue the small round tops of the signal lamps in place, I would suggest a small spot of PVA or contact cement if you might decide to add LED lighting at a later stage.
HO Fine Detail and 7mm Scale ladders and safety handrails are to be supplied by the purchaser which will produce a finer result. Etched brass HO and 7mm Scale ladder kits can be obtained from Keiran Ryan Models. 7mm Scale safety handrails can be made from strip brass section and HO from brass wire or fine strip brass section.
- Servo control such as Tam Valley Singlet
- Relay using a wire mounted to the ‘clapper’ of the relay
- A ‘push/pull’ rod from the edge of the layout including bellcranks as required.
- Working signal levers can be obtained from the following suppliers:
- A ‘wire in tube’ (Bowden cable style) from the edge of the layout. Modratec (above) sells wire in tube systems.
- Using linen thread, fishing line or similar through screw eyelets with a lead fishing sinker attached below the short arm on the opposite side of the main crank as a counterweight.
- Muscle wire (SMA – Shape memory Alloy) – You will have to work this one out. Anton’s Train did sell muscle wire actuators.
Program the servo for the movement end points following the Tam Valley procedure. If you used double sided tape and you are happy with the operation screw the servo mounting in place.
At this stage you can make another order then contact the Shapeways Service Team and request that the new order by sent with the first order to save on the shipping cost for one item. Shapeways have done this previously so there should not be a problem but do it quickly while the first order is still being printed.