EMPCCCC
This page last updated: December 21, 2012 as of May 2014
Landscape Bridges : Walthers motorized double track swing
- Building instructions
- Base... 1'x4'x3/4" pine (from Brazil) with upright 2x4 'river' and cork + flat 2x4 + 3/4" pine (from Sweden) 'ground' : thus built for a ~3.5" deep resin river with ~2.5" banks, unfinished end awaiting bridge completion for correct placement (yeah the
Alpha Battery (Atomic Annie) mini subs will be in the resin river :) There is a 1x2" base for the base so all the wiring will not get mangled whenever it is moved and will reduce warpage in the warp age.
- Walthers bridge was designed for a FLAT -no depth- river, even then, resin would creep up and into the base...
- There is a ~9" landing at each end where rerailers will be to assist bridge traversal.
- All the wires will need to go down through-past the base and have an electrical nightmare in the dark subterranean region.
- Bridge... plastic kit parts partially assembled ... awaiting track and switches ... To be continued...
- additional parts needed are bridge track, Walthers motorizing motor, DPDT switch, LEDs, styrene and lotsa wire and a place to put the bridge ~about 4'x4'... possibly 2 Tamiya switches as Walthers packed ones that dont fit-work. Better yet : Contact Walthers and they will send two replacement switches.
- The kit seems well made and the instructions-diagrams are good... except for the switches and the gear has knobs on every axis - cut off all EXCEPT for the one that should be there - or glue one on after it is cut off thinking it is sprue squeee. Dunno how it would have been if i used code 83 bridge track - Part #10 did not work for me so i cut off the ridges where the trusses interfered. It could have had LEDs... it IS 2014. Link to United States Coast Guard : bridge lighting diagrams pdf
tamiya 5A Micro Switch Item #75016 2ea @ $2.70 = $5.40 & Shipping: $5.00 = Total: $10.40
- Wiring diagram -a DPDT- is not that and i dont understand what they intend or how to wire it. Run black wires from BOTH DPDT switch poles to motor wire. From EACH DPDT switch poles run a Red wire to C on EACH micro switch and from NC on to the motor wire. Test the motor and switch so the bridge rotates correctly. One switch will have Red&Black wires connecting to the motors wires and the Other switch Must be reversed so its red connects to motor black and its black to motor red. Make it so one DPDT toggle sends the bridge rotating one way and toggleing to the other side sends the bridge rotating the other way. Use the 2 diodes for some other project. I used a screw terminal so the wires could become unfastened easily for setup and for extra long maintenace tasks.
- OK on the Walthers diagram the DPDT switch has the power connected and reversed on the end poles - Note there should be a hump where they cross to indicate that they DO NOT CONNECT - they are to go to opposite poles on the switch... Since the world has not dissolved, using the diagram must work ... i prefer my way.
- Do NOT glue the tops onto the bridge piers. They have screw holes in them - use them and allow the tops to be removeable especially on the end that has the toggle switch so it can be adjusted and fixed when the bridge bends the toggle.
- Bridge track mystifies me - it would seem the rerailing part would be AFTER going onto the bridge, from what i can see-tell that is what real bridges do.
- Location Location Location ...
- Double track Swing bridge ...google maps over the Milwaukee river at S Water St Milwaukee, WI and there is another just South-South-West SSW 8000' near S 1st St over the Kinnickinnic river. They are different than Walthers but about the same length and are double track.
- Power seems to come UP from the river at the mid river protection and be wired across to the center of the bridge for power and lights. One has a stucture on top and the SSW one does not -just a wire frame to hold the wires and lights.
- There is Protection (fenders piers dolphins) for the bridge in the open position at both bridges.
Two links for the protection piers that look good to me. The Milwaukee bridges have high water, these do not so the protection is visible - and they are side views. The left is it, the right might be a different bridge. flickr photo and bridgehunter photo
bridgehunter info : CSX Curtis Creek Drawbridge (Anne Arundel County, Maryland) Through truss bridge over Curtis Creek on CSX Transportation (former Baltimore & Ohio RR,) You know you are there if there are sunken boats around the corner:)
- The bridge is 27" long and ends up needing 30+ inches in length and since it rotates it needs a little more than that in width since there needs to be bridge protection piers and planking and metal guards around the outside of the bridge.
- Wiring ... junction boxes (breadboard) are handy so the wires can be joined and disassembled
- After the toggle switches are installed the bridge can no longer be spinned like a roulette wheel - that would bend the toggles.
- After the motor is installed the bridge can only be turned using power. Do NOT spin it and break the gears and/or other plastic thingys.
- Track wires have to go down through the rotating spindle with enough slack to lift off the bridge for maintenance. Drill holes through the boxes and the corner of the bridge so the wires can go from under the tracks over and down the rabbit hole. Glueing on the track was done Before mounting the bridge sides - and that was hard enough - dunno how it would have been with the bridge sides in the way - Code 100 Shinohara bridge flex track was used, might have been diferent with Walthers bridge track - but it is code 80:(
- Motor and one of the switches are in the base -their wires have to go down the big hole and out to wherever the DPDT switch is located. The abutment switch wires have to go from the switch down around and wherever the DPDT switch is located AND back inside to the Motor. The wires need to kept as 'pairs' of black and red... or 'pairs' of r/b y/g or however it is easiest to keep them paired.
- Wires for the LEDs ON the bridge and the bridge protection can come UP through the river just like the prototype. The bridge wires will be up in the air to the top middle of the bridge, while the protection wires will go along the protection.
- Notice the construction of a metal frame and a house on top of the bridge to receive the wires from the pole on the protection pier.
- There are silver things at the top of the bridge ends and above the house to hold the LEDs.
- Wires for the LEDs ON the bridge abutments can go down through the wood to the power source.
- I used a 4.5 V wall wart to power the bridge and for LEDs. Actually it is a variable and 4.5 is selected. Tested using a train transformer and about 4.5 seemed good to me. YMMV
- Belong together...
- Bridge protection... will be scratch built from 1/4" dowel rods and balsa strips. The top will be at the height of the concrete of the turntable. Two layers of strips above water and ?several? below the crest of the resin river. Weathering to resemble 'high water' on the protection pier and the concrete structures. It will be quite a project building the protection... and not able to be done until the bridge is in place and the river and banks are built. This bridge would be much simpler to build on a 'flat' river .. but then there would be no mini-sub traffic.
- Weathering the dowels and balsa planks was done using alcohol and leather shoe dye... stuff i just had left over. It only takes a minute to get the weathered effect... too long soaking and they turned too dark. YMMV.
- LED lighting
- R/G lights ON the bridge...
- Red lights on protection pier around the bridge
- Shore Red lights : 1 at bridge pier, 1 each at end of bridge protection (will be LED on a buoy) : Red-Striped White Buoy : "Do not pass between buoy and nearest shore"
- Planes and boats have green light on right and red light on left...
- Much to do .. much to do...
- Plan to make an 18" protection pier river area on one side and a 24" on the other with a pair of Custom Model Railroads double track Rolling lift bridges near the edge. Still debating using their lift bridge... the problem would be making it lift .. the Rolling lift bridge is made to be motorized, the lift bridge - not so much.
- Gallon of polyester resin costs ~$80. 2'x4' = 8 sq ft : a gallon of water covers a 2'x3' pan at a depth of less than half inch. So it will take probably more than 10 gallons to fill the resin river. ouch and stinky and hope it dont crack.
- So how about using acrylic plexiglass .. it would be near impossible to have any water inside the protection piers where the mini sub port will be...
- Current as of : 2014_02_16...
- Current as of : 2014_04_13...
Copyright © 1991..2014 by Ivan Lee Herring
